🔖 Release version 0.141.1 (#16106 )

Co-authored-by: github-actions[bot] <github-actions[bot]@users.noreply.github.com>
📝 Update release notes
2026-09-08 11:35:12 -04:00 · 2026-07-29 17:15:38 +00:00 · 2026-07-29 17:05:15 +00:00 · 2026-07-29 19:04:36 +02:00 · 2026-07-29 15:32:23 +00:00 · 2026-07-29 17:27:41 +02:00
30 changed files with 1620 additions and 227 deletions
@@ -40,11 +40,7 @@ jobs:
        if: ${{ github.event_name == 'workflow_dispatch' && github.event.inputs.debug_enabled == 'true' }}
        with:
          limit-access-to-actor: true
-      - uses: tiangolo/latest-changes@c9b73efbc8992ef1a401e4235ea307a8ca8a724b # 0.6.1
+      - uses: tiangolo/latest-changes@8a940392f4c65274539453a5d5a76d9550203ac1 # 0.7.1
        with:
          token: ${{ secrets.GITHUB_TOKEN }}
-          latest_changes_file: docs/en/docs/release-notes.md
-          latest_changes_header: '## Latest Changes'
-          end_regex: '^## '
          debug_logs: true
-          label_header_prefix: '### '
@@ -201,6 +201,78 @@ jobs:
          mode: memory
          run: uv run --no-sync pytest tests/memory_benchmarks --codspeed

+  regression-test:
+    runs-on: ubuntu-latest
+    timeout-minutes: 10
+    steps:
+      - name: Check out the pull request
+        if: github.event_name == 'pull_request'
+        uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7.0.0
+        with:
+          ref: ${{ github.sha }}
+          path: pr
+          persist-credentials: false
+          fetch-depth: 0
+      - name: Find changed tests
+        if: github.event_name == 'pull_request'
+        id: changed-tests
+        working-directory: pr
+        env:
+          BASE_SHA: ${{ github.event.pull_request.base.sha }}
+          HEAD_SHA: ${{ github.event.pull_request.head.sha }}
+        run: |
+          git diff --name-only --diff-filter=AM -z "$BASE_SHA" "$HEAD_SHA" -- tests \
+            | while IFS= read -r -d '' file; do
+                case "$(basename "$file")" in
+                  test_*.py) printf '%s\0' "$file" ;;
+                esac
+              done > "$RUNNER_TEMP/changed-tests"
+          if [ -s "$RUNNER_TEMP/changed-tests" ]; then
+            echo "found=true" >> "$GITHUB_OUTPUT"
+            git diff --binary "$BASE_SHA" "$HEAD_SHA" -- tests \
+              > "$RUNNER_TEMP/tests.patch"
+          else
+            echo "found=false" >> "$GITHUB_OUTPUT"
+            echo "No added or modified test files; regression proof is not applicable."
+          fi
+      - name: Check out the base revision
+        if: steps.changed-tests.outputs.found == 'true'
+        uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7.0.0
+        with:
+          ref: ${{ github.event.pull_request.base.sha }}
+          path: base
+          persist-credentials: false
+      - name: Set up Python
+        if: steps.changed-tests.outputs.found == 'true'
+        uses: actions/setup-python@ece7cb06caefa5fff74198d8649806c4678c61a1 # v6.3.0
+        with:
+          python-version-file: "base/.python-version"
+      - name: Setup uv
+        if: steps.changed-tests.outputs.found == 'true'
+        uses: astral-sh/setup-uv@d31148d669074a8d0a63714ba94f3201e7020bc3 # v8.3.0
+        with:
+          # Before upgrading uv version, make sure astral-sh/setup-uv knows its checksum.
+          # See: https://github.com/astral-sh/setup-uv/issues/851#issuecomment-4282017837
+          version: "0.11.18"
+          enable-cache: true
+      - name: Run the changed tests against the base code
+        if: steps.changed-tests.outputs.found == 'true'
+        working-directory: base
+        run: |
+          git apply "$RUNNER_TEMP/tests.patch"
+          uv sync --locked --no-dev --group tests --extra all
+          set +e
+          xargs -0 uv run --no-sync pytest -- < "$RUNNER_TEMP/changed-tests"
+          status=$?
+          set -e
+          if [ "$status" -eq 0 ]; then
+            echo "::warning::The changed tests already pass on the base revision. Check whether the fix is still needed."
+            echo "### Regression proof: base already passes :warning:" >> "$GITHUB_STEP_SUMMARY"
+            echo "The changed tests pass without the pull request's code changes." >> "$GITHUB_STEP_SUMMARY"
+          else
+            echo "The changed tests fail on the base revision as expected (pytest exit code $status)."
+            echo "### Regression proof: base fails as expected :white_check_mark:" >> "$GITHUB_STEP_SUMMARY"
+          fi
  coverage-combine:
    needs:
      - test
@@ -253,6 +325,7 @@ jobs:
      - test
      - coverage-combine
      - benchmark
+      - regression-test
    runs-on: ubuntu-latest
    timeout-minutes: 5
    steps:
@@ -119,6 +119,10 @@ Running `fastapi dev` initiates development mode.

 By default, **auto-reload** is enabled, automatically reloading the server when you make changes to your code. This is resource-intensive and could be less stable than when it's disabled. You should only use it for development. It also listens on the IP address `127.0.0.1`, which is the IP for your machine to communicate with itself alone (`localhost`).

+Before importing your app, `fastapi dev` sets the `FASTAPI_ENV` environment variable to `development`. If `FASTAPI_ENV` is already set, its existing value is preserved. This lets app startup code choose development-friendly behavior while allowing you to provide an app-specific environment such as `staging`.
+
+The conventional `FASTAPI_ENV` values are `development` and `production`. `fastapi run` currently leaves `FASTAPI_ENV` unchanged, so set it explicitly if your app needs to detect production mode.
+
 ## `fastapi run` { #fastapi-run }

 Executing `fastapi run` starts FastAPI in production mode.
@@ -0,0 +1,17 @@
+# Server-Sent Events - `EventSourceResponse` and `ServerSentEvent`
+
+To stream Server-Sent Events (SSE), use `yield` in your *path operation function* and set `response_class=EventSourceResponse`.
+
+If you need to set SSE fields like `event`, `id`, `retry`, or `comment`, you can `yield` `ServerSentEvent` objects instead of plain data.
+
+Read more about it in the [FastAPI docs for Server-Sent Events (SSE)](https://fastapi.tiangolo.com/tutorial/server-sent-events/).
+
+You can import them directly from `fastapi.sse`:
+
+```python
+from fastapi.sse import EventSourceResponse, ServerSentEvent
+```
+
+::: fastapi.sse.EventSourceResponse
+
+::: fastapi.sse.ServerSentEvent
@@ -7,6 +7,126 @@ hide:

 ## Latest Changes

+## 0.141.1 (2026-07-29)
+
+### Fixes
+
+* 🐛 Fix support for background tasks and headers from dependencies in `app.frontend()`. PR [#16105](https://github.com/fastapi/fastapi/pull/16105) by [@tiangolo](https://github.com/tiangolo).
+
+### Docs
+
+* 📝 Document `FASTAPI_ENV` in FastAPI CLI guide. PR [#16104](https://github.com/fastapi/fastapi/pull/16104) by [@tiangolo](https://github.com/tiangolo).
+
+## 0.141.0 (2026-07-29)
+
+### Features
+
+* ✨ Add `app.frontend(check_dir="auto")`, to make local development more convenient with `fastapi dev`. PR [#16102](https://github.com/fastapi/fastapi/pull/16102) by [@tiangolo](https://github.com/tiangolo).
+
+## 0.140.13 (2026-07-28)
+
+### Fixes
+
+* 🐛 Fix `status_code` being ignored for SSE and JSONL streaming endpoints. PR [#15937](https://github.com/fastapi/fastapi/pull/15937) by [@SAURABHSALVE](https://github.com/SAURABHSALVE).
+
+### Docs
+
+* 📝 Fix `format_sse_event` docstring rendering of `\n\n` terminator. PR [#15613](https://github.com/fastapi/fastapi/pull/15613) by [@AshNicolus](https://github.com/AshNicolus).
+* 📝 Add API reference page for fastapi.sse. PR [#15930](https://github.com/fastapi/fastapi/pull/15930) by [@SAURABHSALVE](https://github.com/SAURABHSALVE).
+
+## 0.140.12 (2026-07-28)
+
+### Fixes
+
+* 🐛 Fix line splitting in `format_sse_event` to comply with SSE spec. PR [#15515](https://github.com/fastapi/fastapi/pull/15515) by [@Zawwarsami16](https://github.com/Zawwarsami16).
+
+## 0.140.11 (2026-07-28)
+
+### Fixes
+
+* 🐛 Fix `response_model_*` params ignored for non-generator endpoints with `Iterable[..]` return type. PR [#15093](https://github.com/fastapi/fastapi/pull/15093) by [@YuriiMotov](https://github.com/YuriiMotov).
+
+## 0.140.10 (2026-07-28)
+
+### Fixes
+
+* 🐛 Fix handling sequences with nested Annotated types. PR [#14874](https://github.com/fastapi/fastapi/pull/14874) by [@YuriiMotov](https://github.com/YuriiMotov).
+
+### Internal
+
+* 🐛 Accept any base test failure as regression. PR [#16092](https://github.com/fastapi/fastapi/pull/16092) by [@tiangolo](https://github.com/tiangolo).
+* 🐛 Preserve pytest exit code in regression check. PR [#16091](https://github.com/fastapi/fastapi/pull/16091) by [@tiangolo](https://github.com/tiangolo).
+* ✅ Test PR regressions against base code. PR [#16090](https://github.com/fastapi/fastapi/pull/16090) by [@tiangolo](https://github.com/tiangolo).
+
+## 0.140.9 (2026-07-28)
+
+### Fixes
+
+* 🐛 Fix `exclude_defaults` not propagated to dict keys and values in `jsonable_encoder`. PR [#16043](https://github.com/fastapi/fastapi/pull/16043) by [@MBGrao](https://github.com/MBGrao).
+
+### Internal
+
+* ⬆ Bump gitpython from 3.1.50 to 3.1.54. PR [#16047](https://github.com/fastapi/fastapi/pull/16047) by [@dependabot[bot]](https://github.com/apps/dependabot).
+* ⬆ Bump pymdown-extensions from 10.21.3 to 11.0. PR [#16048](https://github.com/fastapi/fastapi/pull/16048) by [@dependabot[bot]](https://github.com/apps/dependabot).
+* ⬆ Bump pyasn1 from 0.6.3 to 0.6.4. PR [#16045](https://github.com/fastapi/fastapi/pull/16045) by [@dependabot[bot]](https://github.com/apps/dependabot).
+
+## 0.140.8 (2026-07-28)
+
+### Fixes
+
+* 🐛 Fix stream item type lost when using `include_router()`. PR [#15077](https://github.com/fastapi/fastapi/pull/15077) by [@alex-raw](https://github.com/alex-raw).
+
+## 0.140.7 (2026-07-27)
+
+### Refactors
+
+* ⚡️ Avoid flattening dependencies for OpenAPI. PR [#16076](https://github.com/fastapi/fastapi/pull/16076) by [@tiangolo](https://github.com/tiangolo).
+
+### Internal
+
+* ⬆️ Upgrade latest-changes to 0.7.1. PR [#16077](https://github.com/fastapi/fastapi/pull/16077) by [@tiangolo](https://github.com/tiangolo).
+* 👷 Add OpenAPI dependency benchmarks. PR [#16075](https://github.com/fastapi/fastapi/pull/16075) by [@tiangolo](https://github.com/tiangolo).
+
+## 0.140.6 (2026-07-27)
+
+### Refactors
+
+* ⚡️ Avoid flattening dependencies for request parameters, mainly for OpenAPI. PR [#16073](https://github.com/fastapi/fastapi/pull/16073) by [@tiangolo](https://github.com/tiangolo).
+
+## 0.140.5 (2026-07-27)
+
+### Refactors
+
+* ⚡️ Avoid flattening dependencies for body fields. PR [#16071](https://github.com/fastapi/fastapi/pull/16071) by [@tiangolo](https://github.com/tiangolo).
+
+## 0.140.4 (2026-07-27)
+
+### Refactors
+
+* ⚡️ Skip unused dependency repeat bookkeeping. PR [#16069](https://github.com/fastapi/fastapi/pull/16069) by [@tiangolo](https://github.com/tiangolo).
+
+## 0.140.3 (2026-07-27)
+
+### Refactors
+
+* ⚡️ Avoid repeated dependency flattening in OpenAPI. PR [#16067](https://github.com/fastapi/fastapi/pull/16067) by [@tiangolo](https://github.com/tiangolo).
+
+## 0.140.2 (2026-07-27)
+
+### Refactors
+
+* ⚡️ Stop retaining flat dependency trees. PR [#16065](https://github.com/fastapi/fastapi/pull/16065) by [@tiangolo](https://github.com/tiangolo).
+
+### Internal
+
+* 👷 Add new memory benchmark. PR [#16064](https://github.com/fastapi/fastapi/pull/16064) by [@tiangolo](https://github.com/tiangolo).
+
+## 0.140.1 (2026-07-27)
+
+### Refactors
+
+* ♻️ Update the lru_cache limit for dependencies to account for large apps. PR [#16062](https://github.com/fastapi/fastapi/pull/16062) by [@tiangolo](https://github.com/tiangolo).
+
 ## 0.140.0 (2026-07-24)

 ### Refactors
@@ -106,9 +106,13 @@ Then missing frontend paths return the normal `404`.

 ## Check Directory { #check-directory }

-By default, `app.frontend()` checks that the directory exists when the app is created.
+By default, `app.frontend()` uses `check_dir="auto"`.

-This helps catch configuration errors early. For example, if the frontend build output directory is missing, **FastAPI** will raise an error on startup.
+When the `FASTAPI_ENV` environment variable is set to `development`, **FastAPI** only shows a warning if the frontend build output directory is missing. The [`fastapi dev` command](https://github.com/fastapi/fastapi-cli#fastapi-dev) sets this environment variable for you if it is not already set. This lets you start the backend before building or starting the frontend during development.
+
+In any other environment, **FastAPI** raises an error when the app is created. This helps catch configuration errors early before deploying an app without its frontend files.
+
+You can also set `check_dir=True` to always check the directory when the app is created.

 If your frontend files are created later, for example by a separate build step after the app object is created, set `check_dir=False`:

@@ -132,6 +136,8 @@ Frontend responses run inside the normal **FastAPI** application, so HTTP middle

 Dependencies from the app, from an `APIRouter`, and from `include_router()` also apply to frontend responses. This can be useful for protecting a frontend with cookie authentication or similar.

+Dependencies can also modify response headers and add background tasks, as with normal *path operations*.
+
 ## Static Build Output Only { #static-build-output-only }

 `app.frontend()` serves files already generated by your frontend build.
@@ -211,6 +211,7 @@ nav:
  - reference/httpconnection.md
  - reference/response.md
  - reference/responses.md
+  - reference/sse.md
  - reference/middleware.md
  - "":
    - reference/openapi/index.md
@@ -1,6 +1,6 @@
 """FastAPI framework, high performance, easy to learn, fast to code, ready for production"""

-__version__ = "0.140.0"
+__version__ = "0.141.1"

 from starlette import status as status

@@ -63,6 +63,10 @@ def _annotation_is_sequence(annotation: type[Any] | None) -> bool:

 def field_annotation_is_sequence(annotation: type[Any] | None) -> bool:
    origin = get_origin(annotation)
+
+    if origin is Annotated:
+        return field_annotation_is_sequence(get_args(annotation)[0])
+
    if origin is Union or origin is UnionType:
        for arg in get_args(annotation):
            if field_annotation_is_sequence(arg):
@@ -108,6 +112,10 @@ def field_annotation_is_scalar(annotation: Any) -> bool:

 def field_annotation_is_scalar_sequence(annotation: type[Any] | None) -> bool:
    origin = get_origin(annotation)
+
+    if origin is Annotated:
+        return field_annotation_is_scalar_sequence(get_args(annotation)[0])
+
    if origin is Union or origin is UnionType:
        at_least_one_scalar_sequence = False
        for arg in get_args(annotation):
@@ -1247,13 +1247,16 @@ class FastAPI(Starlette):
            ),
        ] = "auto",
        check_dir: Annotated[
-            bool,
+            bool | Literal["auto"],
            Doc(
                """
-                Check that the frontend directory exists when the app is created.
+                Check that the frontend directory exists when the app is created. When
+                set to `"auto"`, skip the check with a warning when `FASTAPI_ENV` is
+                `"development"`, and check it otherwise. The `fastapi dev` command
+                sets `FASTAPI_ENV` to `"development"` if it is not already set.
                """
            ),
-        ] = True,
+        ] = "auto",
    ) -> None:
        """
        Serve a static frontend build as low-priority routes.
@@ -1285,6 +1288,9 @@ class FastAPI(Starlette):
        app.frontend("/", directory="dist")
        ```
        """
+        check_dir = routing._resolve_frontend_check_dir(
+            directory=directory, check_dir=check_dir
+        )
        self.router.frontend(
            path,
            directory=directory,
@@ -52,6 +52,7 @@ class Dependant:


 _UsesScopesCache = dict[int, tuple[Dependant, bool]]
+_CALLABLE_CLASSIFICATION_CACHE_SIZE = 4096


 class _CallIdentity:
@@ -133,11 +134,7 @@ def _get_security_scheme(*, dependant: Dependant) -> SecurityBase:
    return unwrapped


-def _get_security_dependencies(*, dependant: Dependant) -> list[Dependant]:
-    return [dep for dep in dependant.dependencies if _is_security_scheme(dependant=dep)]
-
-
-@lru_cache(maxsize=1024)
+@lru_cache(maxsize=_CALLABLE_CLASSIFICATION_CACHE_SIZE)
 def _is_gen_callable_cached(call_identity: _CallIdentity) -> bool:
    call = call_identity.call
    if inspect.isgeneratorfunction(_impartial(call)) or inspect.isgeneratorfunction(
@@ -167,7 +164,7 @@ def _is_gen_callable(call: Callable[..., Any] | None) -> bool:
    return _is_gen_callable_cached(_CallIdentity(call))


-@lru_cache(maxsize=1024)
+@lru_cache(maxsize=_CALLABLE_CLASSIFICATION_CACHE_SIZE)
 def _is_async_gen_callable_cached(call_identity: _CallIdentity) -> bool:
    call = call_identity.call
    if inspect.isasyncgenfunction(_impartial(call)) or inspect.isasyncgenfunction(
@@ -197,7 +194,7 @@ def _is_async_gen_callable(call: Callable[..., Any] | None) -> bool:
    return _is_async_gen_callable_cached(_CallIdentity(call))


-@lru_cache(maxsize=1024)
+@lru_cache(maxsize=_CALLABLE_CLASSIFICATION_CACHE_SIZE)
 def _is_coroutine_callable_cached(call_identity: _CallIdentity) -> bool:
    call = call_identity.call
    if inspect.isroutine(_impartial(call)) and iscoroutinefunction(_impartial(call)):
@@ -144,74 +144,14 @@ def get_parameterless_sub_dependant(*, depends: params.Depends, path: str) -> De
    )


-def get_flat_dependant(
-    dependant: Dependant,
-    *,
-    skip_repeats: bool = False,
-    visited: list[DependencyCacheKey] | None = None,
-    parent_oauth_scopes: list[str] | None = None,
-    _uses_scopes_cache: _UsesScopesCache | None = None,
-) -> Dependant:
-    if visited is None:
-        visited = []
-    if _uses_scopes_cache is None:
-        _uses_scopes_cache = {}
-    visited.append(
-        _get_cache_key(
-            dependant=dependant,
-            uses_scopes_cache=_uses_scopes_cache,
-        )
-    )
-    use_parent_oauth_scopes = (parent_oauth_scopes or []) + (
-        _get_oauth_scopes(dependant=dependant)
-    )
-
-    flat_dependant = Dependant(
-        path_params=dependant.path_params.copy(),
-        query_params=dependant.query_params.copy(),
-        header_params=dependant.header_params.copy(),
-        cookie_params=dependant.cookie_params.copy(),
-        body_params=dependant.body_params.copy(),
-        name=dependant.name,
-        call=dependant.call,
-        request_param_name=dependant.request_param_name,
-        websocket_param_name=dependant.websocket_param_name,
-        http_connection_param_name=dependant.http_connection_param_name,
-        response_param_name=dependant.response_param_name,
-        background_tasks_param_name=dependant.background_tasks_param_name,
-        security_scopes_param_name=dependant.security_scopes_param_name,
-        own_oauth_scopes=dependant.own_oauth_scopes,
-        parent_oauth_scopes=use_parent_oauth_scopes,
-        use_cache=dependant.use_cache,
-        path=dependant.path,
-        scope=dependant.scope,
-    )
-    for sub_dependant in dependant.dependencies:
-        if (
-            skip_repeats
-            and _get_cache_key(
-                dependant=sub_dependant,
-                uses_scopes_cache=_uses_scopes_cache,
-            )
-            in visited
-        ):
-            continue
-        flat_sub = get_flat_dependant(
-            sub_dependant,
-            skip_repeats=skip_repeats,
-            visited=visited,
-            parent_oauth_scopes=_get_oauth_scopes(dependant=flat_dependant),
-            _uses_scopes_cache=_uses_scopes_cache,
-        )
-        flat_dependant.dependencies.append(flat_sub)
-        flat_dependant.path_params.extend(flat_sub.path_params)
-        flat_dependant.query_params.extend(flat_sub.query_params)
-        flat_dependant.header_params.extend(flat_sub.header_params)
-        flat_dependant.cookie_params.extend(flat_sub.cookie_params)
-        flat_dependant.body_params.extend(flat_sub.body_params)
-        flat_dependant.dependencies.extend(flat_sub.dependencies)
-
-    return flat_dependant
+def _get_flat_body_params(dependant: Dependant) -> list[ModelField]:
+    body_params: list[ModelField] = []
+    dependants = [dependant]
+    while dependants:
+        current_dependant = dependants.pop()
+        body_params.extend(current_dependant.body_params)
+        dependants.extend(reversed(current_dependant.dependencies))
+    return body_params


 def _get_flat_fields_from_params(fields: list[ModelField]) -> list[ModelField]:
@@ -227,11 +167,31 @@ def _get_flat_fields_from_params(fields: list[ModelField]) -> list[ModelField]:


 def get_flat_params(dependant: Dependant) -> list[ModelField]:
-    flat_dependant = get_flat_dependant(dependant, skip_repeats=True)
-    path_params = _get_flat_fields_from_params(flat_dependant.path_params)
-    query_params = _get_flat_fields_from_params(flat_dependant.query_params)
-    header_params = _get_flat_fields_from_params(flat_dependant.header_params)
-    cookie_params = _get_flat_fields_from_params(flat_dependant.cookie_params)
+    path_params: list[ModelField] = []
+    query_params: list[ModelField] = []
+    header_params: list[ModelField] = []
+    cookie_params: list[ModelField] = []
+    visited: list[DependencyCacheKey] = []
+    uses_scopes_cache: _UsesScopesCache = {}
+    dependants = [dependant]
+    while dependants:
+        current_dependant = dependants.pop()
+        cache_key = _get_cache_key(
+            dependant=current_dependant,
+            uses_scopes_cache=uses_scopes_cache,
+        )
+        if cache_key in visited:
+            continue
+        visited.append(cache_key)
+        path_params.extend(current_dependant.path_params)
+        query_params.extend(current_dependant.query_params)
+        header_params.extend(current_dependant.header_params)
+        cookie_params.extend(current_dependant.cookie_params)
+        dependants.extend(reversed(current_dependant.dependencies))
+    path_params = _get_flat_fields_from_params(path_params)
+    query_params = _get_flat_fields_from_params(query_params)
+    header_params = _get_flat_fields_from_params(header_params)
+    cookie_params = _get_flat_fields_from_params(cookie_params)
    return path_params + query_params + header_params + cookie_params


@@ -1038,8 +998,8 @@ async def request_body_to_args(
    return values, errors


-def get_body_field(
-    *, flat_dependant: Dependant, name: str, embed_body_fields: bool
+def _get_body_field(
+    *, body_params: list[ModelField], name: str, embed_body_fields: bool
 ) -> ModelField | None:
    """
    Get a ModelField representing the request body for a path operation, combining
@@ -1051,34 +1011,30 @@ def get_body_field(
    This is **not** used to validate/parse the request body, that's done with each
    individual body parameter.
    """
-    if not flat_dependant.body_params:
+    if not body_params:
        return None
-    first_param = flat_dependant.body_params[0]
+    first_param = body_params[0]
    if not embed_body_fields:
        return first_param
    model_name = "Body_" + name
-    BodyModel = create_body_model(
-        fields=flat_dependant.body_params, model_name=model_name
-    )
-    required = any(
-        True for f in flat_dependant.body_params if f.field_info.is_required()
-    )
+    BodyModel = create_body_model(fields=body_params, model_name=model_name)
+    required = any(True for f in body_params if f.field_info.is_required())
    BodyFieldInfo_kwargs: dict[str, Any] = {
        "annotation": BodyModel,
        "alias": "body",
    }
    if not required:
        BodyFieldInfo_kwargs["default"] = None
-    if any(isinstance(f.field_info, params.File) for f in flat_dependant.body_params):
+    if any(isinstance(f.field_info, params.File) for f in body_params):
        BodyFieldInfo: type[params.Body] = params.File
-    elif any(isinstance(f.field_info, params.Form) for f in flat_dependant.body_params):
+    elif any(isinstance(f.field_info, params.Form) for f in body_params):
        BodyFieldInfo = params.Form
    else:
        BodyFieldInfo = params.Body

        body_param_media_types = [
            f.field_info.media_type
-            for f in flat_dependant.body_params
+            for f in body_params
            if isinstance(f.field_info, params.Body)
        ]
        if len(set(body_param_media_types)) == 1:
@@ -299,6 +299,7 @@ def jsonable_encoder(
                    key,
                    by_alias=by_alias,
                    exclude_unset=exclude_unset,
+                    exclude_defaults=exclude_defaults,
                    exclude_none=exclude_none,
                    custom_encoder=custom_encoder,
                    sqlalchemy_safe=sqlalchemy_safe,
@@ -307,6 +308,7 @@ def jsonable_encoder(
                    value,
                    by_alias=by_alias,
                    exclude_unset=exclude_unset,
+                    exclude_defaults=exclude_defaults,
                    exclude_none=exclude_none,
                    custom_encoder=custom_encoder,
                    sqlalchemy_safe=sqlalchemy_safe,
@@ -3,6 +3,7 @@ import http.client
 import inspect
 import warnings
 from collections.abc import Sequence
+from dataclasses import dataclass, field
 from typing import Any, Literal, cast

 from fastapi import routing
@@ -17,13 +18,14 @@ from fastapi._compat import (
 from fastapi.datastructures import DefaultPlaceholder, _Unset
 from fastapi.dependencies.models import (
    Dependant,
+    _get_cache_key,
    _get_oauth_scopes,
-    _get_security_dependencies,
    _get_security_scheme,
+    _is_security_scheme,
+    _UsesScopesCache,
 )
 from fastapi.dependencies.utils import (
    _get_flat_fields_from_params,
-    get_flat_dependant,
    get_flat_params,
    get_validation_alias,
 )
@@ -34,7 +36,7 @@ from fastapi.openapi.models import OpenAPI
 from fastapi.params import Body, ParamTypes
 from fastapi.responses import Response
 from fastapi.sse import _SSE_EVENT_SCHEMA
-from fastapi.types import ModelNameMap
+from fastapi.types import DependencyCacheKey, ModelNameMap
 from fastapi.utils import (
    deep_dict_update,
    generate_operation_id_for_path,
@@ -83,13 +85,57 @@ status_code_ranges: dict[str, str] = {
 }


-def get_openapi_security_definitions(
-    flat_dependant: Dependant,
+@dataclass
+class _OpenAPIDependencyData:
+    path_params: list[ModelField] = field(default_factory=list)
+    query_params: list[ModelField] = field(default_factory=list)
+    header_params: list[ModelField] = field(default_factory=list)
+    cookie_params: list[ModelField] = field(default_factory=list)
+    security_dependencies: list[tuple[Dependant, list[str]]] = field(
+        default_factory=list
+    )
+
+
+def _get_openapi_dependency_data(dependant: Dependant) -> _OpenAPIDependencyData:
+    dependency_data = _OpenAPIDependencyData()
+    visited: list[DependencyCacheKey] = []
+    uses_scopes_cache: _UsesScopesCache = {}
+    dependants: list[tuple[Dependant, list[str], bool]] = [(dependant, [], True)]
+    while dependants:
+        current_dependant, parent_oauth_scopes, is_root = dependants.pop()
+        cache_key = _get_cache_key(
+            dependant=current_dependant,
+            uses_scopes_cache=uses_scopes_cache,
+        )
+        if cache_key in visited:
+            continue
+        visited.append(cache_key)
+        dependency_data.path_params.extend(current_dependant.path_params)
+        dependency_data.query_params.extend(current_dependant.query_params)
+        dependency_data.header_params.extend(current_dependant.header_params)
+        dependency_data.cookie_params.extend(current_dependant.cookie_params)
+        oauth_scopes = parent_oauth_scopes.copy()
+        for scope in _get_oauth_scopes(dependant=current_dependant):
+            if scope not in oauth_scopes:
+                oauth_scopes.append(scope)
+        if not is_root and _is_security_scheme(dependant=current_dependant):
+            dependency_data.security_dependencies.append(
+                (current_dependant, oauth_scopes)
+            )
+        dependants.extend(
+            (sub_dependant, oauth_scopes, False)
+            for sub_dependant in reversed(current_dependant.dependencies)
+        )
+    return dependency_data
+
+
+def _get_openapi_security_definitions(
+    security_dependencies: list[tuple[Dependant, list[str]]],
 ) -> tuple[dict[str, Any], list[dict[str, Any]]]:
    security_definitions = {}
    # Use a dict to merge scopes for same security scheme
    operation_security_dict: dict[str, list[str]] = {}
-    for security_dependency in _get_security_dependencies(dependant=flat_dependant):
+    for security_dependency, oauth_scopes in security_dependencies:
        security_scheme = _get_security_scheme(dependant=security_dependency)
        security_definition = jsonable_encoder(
            security_scheme.model,
@@ -101,7 +147,7 @@ def get_openapi_security_definitions(
        # Merge scopes for the same security scheme
        if security_name not in operation_security_dict:
            operation_security_dict[security_name] = []
-        for scope in _get_oauth_scopes(dependant=security_dependency):
+        for scope in oauth_scopes:
            if scope not in operation_security_dict[security_name]:
                operation_security_dict[security_name].append(scope)
    operation_security = [
@@ -112,7 +158,7 @@ def get_openapi_security_definitions(

 def _get_openapi_operation_parameters(
    *,
-    dependant: Dependant,
+    dependency_data: _OpenAPIDependencyData,
    model_name_map: ModelNameMap,
    field_mapping: dict[
        tuple[ModelField, Literal["validation", "serialization"]], dict[str, Any]
@@ -120,11 +166,10 @@ def _get_openapi_operation_parameters(
    separate_input_output_schemas: bool = True,
 ) -> list[dict[str, Any]]:
    parameters = []
-    flat_dependant = get_flat_dependant(dependant, skip_repeats=True)
-    path_params = _get_flat_fields_from_params(flat_dependant.path_params)
-    query_params = _get_flat_fields_from_params(flat_dependant.query_params)
-    header_params = _get_flat_fields_from_params(flat_dependant.header_params)
-    cookie_params = _get_flat_fields_from_params(flat_dependant.cookie_params)
+    path_params = _get_flat_fields_from_params(dependency_data.path_params)
+    query_params = _get_flat_fields_from_params(dependency_data.query_params)
+    header_params = _get_flat_fields_from_params(dependency_data.header_params)
+    cookie_params = _get_flat_fields_from_params(dependency_data.cookie_params)
    parameter_groups = [
        (ParamTypes.path, path_params),
        (ParamTypes.query, query_params),
@@ -132,8 +177,8 @@ def _get_openapi_operation_parameters(
        (ParamTypes.cookie, cookie_params),
    ]
    default_convert_underscores = True
-    if len(flat_dependant.header_params) == 1:
-        first_field = flat_dependant.header_params[0]
+    if len(dependency_data.header_params) == 1:
+        first_field = dependency_data.header_params[0]
        if lenient_issubclass(first_field.field_info.annotation, BaseModel):
            default_convert_underscores = getattr(
                first_field.field_info, "convert_underscores", True
@@ -284,21 +329,33 @@ def get_openapi_path(
    assert current_response_class, "A response class is needed to generate OpenAPI"
    route_response_media_type: str | None = current_response_class.media_type
    if route.include_in_schema:
+        dependency_data = _get_openapi_dependency_data(route.dependant)
+        all_route_params = [
+            field
+            for fields in (
+                dependency_data.path_params,
+                dependency_data.query_params,
+                dependency_data.header_params,
+                dependency_data.cookie_params,
+            )
+            for field in _get_flat_fields_from_params(fields)
+        ]
        for method in route.methods:
            operation = get_openapi_operation_metadata(
                route=route, method=method, operation_ids=operation_ids
            )
            parameters: list[dict[str, Any]] = []
-            flat_dependant = get_flat_dependant(route.dependant, skip_repeats=True)
-            security_definitions, operation_security = get_openapi_security_definitions(
-                flat_dependant=flat_dependant
+            security_definitions, operation_security = (
+                _get_openapi_security_definitions(
+                    security_dependencies=dependency_data.security_dependencies
+                )
            )
            if operation_security:
                operation.setdefault("security", []).extend(operation_security)
            if security_definitions:
                security_schemes.update(security_definitions)
            operation_parameters = _get_openapi_operation_parameters(
-                dependant=route.dependant,
+                dependency_data=dependency_data,
                model_name_map=model_name_map,
                field_mapping=field_mapping,
                separate_input_output_schemas=separate_input_output_schemas,
@@ -458,7 +515,6 @@ def get_openapi_path(
                    deep_dict_update(openapi_response, process_response)
                    openapi_response["description"] = description
            http422 = "422"
-            all_route_params = get_flat_params(route.dependant)
            if (all_route_params or route.body_field) and not any(
                status in operation["responses"]
                for status in [http422, "4XX", "default"]
@@ -9,6 +9,7 @@ import os
 import stat
 import threading
 import types
+import warnings
 from collections.abc import (
    AsyncIterator,
    Awaitable,
@@ -55,10 +56,11 @@ from fastapi.dependencies.models import (
    _is_gen_callable,
 )
 from fastapi.dependencies.utils import (
+    SolvedDependency,
+    _get_body_field,
+    _get_flat_body_params,
    _should_embed_body_fields,
-    get_body_field,
    get_dependant,
-    get_flat_dependant,
    get_parameterless_sub_dependant,
    get_stream_item_type,
    get_typed_return_annotation,
@@ -630,10 +632,13 @@ def get_request_handler(
                    _sse_with_checkpoints(sse_receive_stream)
                )

+                response_args = _build_response_args(
+                    status_code=status_code, solved_result=solved_result
+                )
                response = StreamingResponse(
                    sse_stream_content,
                    media_type="text/event-stream",
-                    background=solved_result.background_tasks,
+                    **response_args,
                )
                response.headers["Cache-Control"] = "no-cache"
                # For Nginx proxies to not buffer server sent events
@@ -666,10 +671,13 @@ def get_request_handler(

                    jsonl_stream_content = _sync_stream_jsonl()

+                response_args = _build_response_args(
+                    status_code=status_code, solved_result=solved_result
+                )
                response = StreamingResponse(
                    jsonl_stream_content,
                    media_type="application/jsonl",
-                    background=solved_result.background_tasks,
+                    **response_args,
                )
                response.headers.raw.extend(solved_result.response.headers.raw)
            elif _is_async_gen_callable(dependant.call) or _is_gen_callable(
@@ -807,7 +815,7 @@ class APIWebSocketRoute(routing.WebSocketRoute):
        self.path_regex, self.path_format, self.param_convertors = compile_path(path)
        (
            self.dependant,
-            self._flat_dependant,
+            _,
            self._embed_body_fields,
        ) = _build_dependant_with_parameterless_dependencies(
            path=self.path_format,
@@ -849,16 +857,16 @@ def _build_dependant_with_parameterless_dependencies(
    path: str,
    call: Callable[..., Any],
    dependencies: Sequence[params.Depends],
-) -> tuple[Dependant, Dependant, bool]:
+) -> tuple[Dependant, list[ModelField], bool]:
    dependant = get_dependant(path=path, call=call, scope="function")
    for depends in dependencies[::-1]:
        dependant.dependencies.insert(
            0,
            get_parameterless_sub_dependant(depends=depends, path=path),
        )
-    flat_dependant = get_flat_dependant(dependant)
-    embed_body_fields = _should_embed_body_fields(flat_dependant.body_params)
-    return dependant, flat_dependant, embed_body_fields
+    body_params = _get_flat_body_params(dependant)
+    embed_body_fields = _should_embed_body_fields(body_params)
+    return dependant, body_params, embed_body_fields


 class _RouteWithPath(Protocol):
@@ -944,7 +952,6 @@ class _APIRouteLike(Protocol):
    description: str
    response_fields: dict[int | str, ModelField]
    dependant: Dependant
-    _flat_dependant: Dependant
    _embed_body_fields: bool
    body_field: ModelField | None
    is_sse_stream: bool
@@ -983,32 +990,11 @@ def _populate_api_route_state(
        generate_unique_id
    ),
    strict_content_type: bool | DefaultPlaceholder = Default(True),
+    stream_item_type: Any | None = None,
 ) -> None:
    route.path = path
    route.endpoint = endpoint
-    route.stream_item_type = None
-    if isinstance(response_model, DefaultPlaceholder):
-        return_annotation = get_typed_return_annotation(endpoint)
-        if lenient_issubclass(return_annotation, Response):
-            response_model = None
-        else:
-            stream_item = get_stream_item_type(return_annotation)
-            if stream_item is not None:
-                # Extract item type for JSONL or SSE streaming when
-                # response_class is DefaultPlaceholder (JSONL) or
-                # EventSourceResponse (SSE).
-                # ServerSentEvent is excluded: it's a transport
-                # wrapper, not a data model, so it shouldn't feed
-                # into validation or OpenAPI schema generation.
-                if (
-                    isinstance(response_class, DefaultPlaceholder)
-                    or lenient_issubclass(response_class, EventSourceResponse)
-                ) and not lenient_issubclass(stream_item, ServerSentEvent):
-                    route.stream_item_type = stream_item
-                response_model = None
-            else:
-                response_model = return_annotation
-    route.response_model = response_model
+    route.stream_item_type = stream_item_type
    route.summary = summary
    route.response_description = response_description
    route.deprecated = deprecated
@@ -1044,27 +1030,6 @@ def _populate_api_route_state(
    if isinstance(status_code, IntEnum):
        status_code = int(status_code)
    route.status_code = status_code
-    if route.response_model:
-        assert is_body_allowed_for_status_code(status_code), (
-            f"Status code {status_code} must not have a response body"
-        )
-        response_name = "Response_" + route.unique_id
-        route.response_field = create_model_field(
-            name=response_name,
-            type_=route.response_model,
-            mode="serialization",
-        )
-    else:
-        route.response_field = None
-    if route.stream_item_type:
-        stream_item_name = "StreamItem_" + route.unique_id
-        route.stream_item_field = create_model_field(
-            name=stream_item_name,
-            type_=route.stream_item_type,
-            mode="serialization",
-        )
-    else:
-        route.stream_item_field = None
    route.dependencies = list(dependencies or [])
    route.description = description or inspect.cleandoc(route.endpoint.__doc__ or "")
    # if a "form feed" character (page break) is found in the description text,
@@ -1091,15 +1056,15 @@ def _populate_api_route_state(
    assert callable(endpoint), "An endpoint must be a callable"
    (
        route.dependant,
-        route._flat_dependant,
+        body_params,
        route._embed_body_fields,
    ) = _build_dependant_with_parameterless_dependencies(
        path=route.path_format,
        call=route.endpoint,
        dependencies=route.dependencies,
    )
-    route.body_field = get_body_field(
-        flat_dependant=route._flat_dependant,
+    route.body_field = _get_body_field(
+        body_params=body_params,
        name=route.unique_id,
        embed_body_fields=route._embed_body_fields,
    )
@@ -1113,6 +1078,49 @@ def _populate_api_route_state(
    route.is_json_stream = is_generator and isinstance(
        response_class, DefaultPlaceholder
    )
+    if isinstance(response_model, DefaultPlaceholder):
+        return_annotation = get_typed_return_annotation(endpoint)
+        if lenient_issubclass(return_annotation, Response):
+            response_model = None
+        else:
+            stream_item = get_stream_item_type(return_annotation)
+            if stream_item is not None and is_generator:
+                # Extract item type for JSONL or SSE streaming for
+                # generator endpoints when response_class is
+                # DefaultPlaceholder (JSONL) or EventSourceResponse (SSE).
+                # ServerSentEvent is excluded: it's a transport
+                # wrapper, not a data model, so it shouldn't feed
+                # into validation or OpenAPI schema generation.
+                if (
+                    isinstance(response_class, DefaultPlaceholder)
+                    or lenient_issubclass(response_class, EventSourceResponse)
+                ) and not lenient_issubclass(stream_item, ServerSentEvent):
+                    route.stream_item_type = stream_item
+                response_model = None
+            else:
+                response_model = return_annotation
+    route.response_model = response_model
+    if route.response_model:
+        assert is_body_allowed_for_status_code(status_code), (
+            f"Status code {status_code} must not have a response body"
+        )
+        response_name = "Response_" + route.unique_id
+        route.response_field = create_model_field(
+            name=response_name,
+            type_=route.response_model,
+            mode="serialization",
+        )
+    else:
+        route.response_field = None
+    if route.stream_item_type:
+        stream_item_name = "StreamItem_" + route.unique_id
+        route.stream_item_field = create_model_field(
+            name=stream_item_name,
+            type_=route.stream_item_type,
+            mode="serialization",
+        )
+    else:
+        route.stream_item_field = None


 class APIRoute(routing.Route):
@@ -1145,7 +1153,6 @@ class APIRoute(routing.Route):
    description: str
    response_fields: dict[int | str, ModelField]
    dependant: Dependant
-    _flat_dependant: Dependant
    _embed_body_fields: bool
    body_field: ModelField | None
    is_sse_stream: bool
@@ -1410,7 +1417,6 @@ class _EffectiveRouteContext:
    description: str = ""
    response_fields: dict[int | str, ModelField] = field(default_factory=dict)
    dependant: Dependant | None = None
-    _flat_dependant: Dependant | None = None
    _embed_body_fields: bool = False
    body_field: ModelField | None = None
    is_sse_stream: bool = False
@@ -1467,6 +1473,7 @@ class _EffectiveRouteContext:
                include_context.included_router.strict_content_type,
                include_context.strict_content_type,
            ),
+            stream_item_type=route.stream_item_type,
        )
        return context

@@ -1486,7 +1493,7 @@ class _EffectiveRouteContext:
        )
        (
            context.dependant,
-            context._flat_dependant,
+            _,
            context._embed_body_fields,
        ) = _build_dependant_with_parameterless_dependencies(
            path="",
@@ -1871,13 +1878,31 @@ def _get_resolved_absolute_path(path: str | os.PathLike[str]) -> str:
    return os.path.realpath(os.fspath(path))


+def _resolve_frontend_check_dir(
+    *,
+    directory: str | os.PathLike[str],
+    check_dir: bool | Literal["auto"],
+) -> bool:
+    if check_dir != "auto":
+        return check_dir
+    if os.environ.get("FASTAPI_ENV") != "development":
+        return True
+    if not os.path.isdir(directory):
+        warnings.warn(
+            f"Frontend directory '{directory}' does not exist. "
+            f"Resolved absolute path: '{_get_resolved_absolute_path(directory)}'",
+            stacklevel=3,
+        )
+    return False
+
+
 class _FrontendStaticFiles(StaticFiles):
    def __init__(
        self,
        *,
        directory: str | os.PathLike[str],
        fallback: Literal["auto", "index.html", "404.html"] | None,
-        check_dir: bool = True,
+        check_dir: bool,
    ) -> None:
        self.fallback = fallback
        if check_dir and not os.path.isdir(directory):
@@ -1912,6 +1937,12 @@ class _FrontendStaticFiles(StaticFiles):
        assert isinstance(path, str)
        return os.path.normpath(os.path.join(*path.split("/")))

+    async def get_response_for_scope(self, scope: Scope) -> Response:
+        if not self.config_checked:
+            await self.check_config()
+            self.config_checked = True
+        return await self.get_response(self.get_path(scope), scope)
+
    async def get_response(self, path: str, scope: Scope) -> Response:
        if scope["method"] not in ("GET", "HEAD"):
            if await self._lookup_static_resource(path) is not None:
@@ -2020,7 +2051,7 @@ class _FrontendRoute(BaseRoute):
        *,
        directory: str | os.PathLike[str],
        fallback: Literal["auto", "index.html", "404.html"] | None = "auto",
-        check_dir: bool = True,
+        check_dir: bool,
    ) -> None:
        if fallback not in {"auto", "index.html", "404.html", None}:
            raise AssertionError(
@@ -2062,7 +2093,8 @@ class _FrontendRoute(BaseRoute):
        return None

    async def handle(self, scope: Scope, receive: Receive, send: Send) -> None:
-        await self.app(scope, receive, send)
+        response = await self.app.get_response_for_scope(scope)
+        await response(scope, receive, send)

    def url_path_for(self, name: str, /, **path_params: Any) -> URLPath:
        raise NoMatchFound(name, path_params)
@@ -2080,7 +2112,7 @@ class _FrontendRouteGroup(BaseRoute):
        self.dependency_overrides_provider = dependency_overrides_provider
        (
            self.dependant,
-            self._flat_dependant,
+            _,
            self._embed_body_fields,
        ) = _build_dependant_with_parameterless_dependencies(
            path="",
@@ -2094,7 +2126,7 @@ class _FrontendRouteGroup(BaseRoute):
        *,
        directory: str | os.PathLike[str],
        fallback: Literal["auto", "index.html", "404.html"] | None = "auto",
-        check_dir: bool = True,
+        check_dir: bool,
    ) -> None:
        self.routes.append(
            _FrontendRoute(
@@ -2165,8 +2197,12 @@ class _FrontendRouteGroup(BaseRoute):
                dependant=dependant,
                dependency_overrides_provider=dependency_overrides_provider,
                embed_body_fields=embed_body_fields,
-            ):
-                await route.handle(scope, receive, send)
+            ) as solved_result:
+                response = await route.app.get_response_for_scope(scope)
+                if response.background is None:
+                    response.background = solved_result.background_tasks
+                response.headers.raw.extend(solved_result.response.headers.raw)
+                await response(scope, receive, send)
            return
        await route.handle(scope, receive, send)

@@ -2186,7 +2222,7 @@ class _FrontendRouteGroup(BaseRoute):
        dependant: Dependant,
        dependency_overrides_provider: Any | None,
        embed_body_fields: bool,
-    ) -> AsyncIterator[None]:
+    ) -> AsyncIterator[SolvedDependency]:
        request = Request(scope, receive, send)
        previous_inner_astack = scope.get("fastapi_inner_astack", _SCOPE_MISSING)
        previous_function_astack = scope.get("fastapi_function_astack", _SCOPE_MISSING)
@@ -2204,7 +2240,7 @@ class _FrontendRouteGroup(BaseRoute):
                    )
                    if solved_result.errors:
                        raise RequestValidationError(solved_result.errors)
-                    yield
+                    yield solved_result
        finally:
            if previous_inner_astack is _SCOPE_MISSING:
                scope.pop("fastapi_inner_astack", None)
@@ -2619,13 +2655,16 @@ class APIRouter(routing.Router):
            ),
        ] = "auto",
        check_dir: Annotated[
-            bool,
+            bool | Literal["auto"],
            Doc(
                """
-                Check that the frontend directory exists when the app is created.
+                Check that the frontend directory exists when the app is created. When
+                set to `"auto"`, skip the check with a warning when `FASTAPI_ENV` is
+                `"development"`, and check it otherwise. The `fastapi dev` command
+                sets `FASTAPI_ENV` to `"development"` if it is not already set.
                """
            ),
-        ] = True,
+        ] = "auto",
    ) -> None:
        """
        Serve a static frontend build as low-priority routes.
@@ -2659,6 +2698,9 @@ class APIRouter(routing.Router):
        app.include_router(router)
        ```
        """
+        check_dir = _resolve_frontend_check_dir(
+            directory=directory, check_dir=check_dir
+        )
        normalized_path = _normalize_frontend_path(path)
        if self._frontend_routes is None:
            self._frontend_routes = _FrontendRouteGroup(
@@ -156,6 +156,12 @@ class ServerSentEvent(BaseModel):
        return self


+def _split_sse_lines(value: str) -> list[str]:
+    # Split on SSE-spec line terminators only (\n, \r\n, \r), preserving
+    # trailing empty strings.
+    return value.replace("\r\n", "\n").replace("\r", "\n").split("\n")
+
+
 def format_sse_event(
    *,
    data_str: Annotated[
@@ -201,19 +207,19 @@ def format_sse_event(
 ) -> bytes:
    """Build SSE wire-format bytes from **pre-serialized** data.

-    The result always ends with `\n\n` (the event terminator).
+    The result always ends with `\\n\\n` (the event terminator).
    """
    lines: list[str] = []

    if comment is not None:
-        for line in comment.splitlines():
+        for line in _split_sse_lines(comment):
            lines.append(f": {line}")

    if event is not None:
        lines.append(f"event: {event}")

    if data_str is not None:
-        for line in data_str.splitlines():
+        for line in _split_sse_lines(data_str):
            lines.append(f"data: {line}")

    if id is not None:
@@ -58,7 +58,7 @@ Changelog = "https://fastapi.tiangolo.com/release-notes/"

 [project.optional-dependencies]
 standard = [
-    "fastapi-cli[standard] >=0.0.8",
+    "fastapi-cli[standard] >=0.0.32",
    "fastar >= 0.9.0",
    # For the test client
    "httpx >=0.23.0,<1.0.0",
@@ -77,7 +77,7 @@ standard = [
 ]

 standard-no-fastapi-cloud-cli = [
-    "fastapi-cli[standard-no-fastapi-cloud-cli] >=0.0.8",
+    "fastapi-cli[standard-no-fastapi-cloud-cli] >=0.0.32",
    # For the test client
    "httpx >=0.23.0,<1.0.0",
    # For templates
@@ -95,7 +95,7 @@ standard-no-fastapi-cloud-cli = [
 ]

 all = [
-    "fastapi-cli[standard] >=0.0.8",
+    "fastapi-cli[standard] >=0.0.32",
    # # For the test client
    "httpx >=0.23.0,<1.0.0",
    # For templates
@@ -0,0 +1,33 @@
+import sys
+
+import pytest
+
+from tests.benchmarks.utils import (
+    ROUTE_COUNT,
+    ROUTE_PATH_PREFIX,
+    create_openapi_app,
+    generate_openapi,
+)
+
+if "--codspeed" not in sys.argv:
+    pytest.skip(
+        "Benchmark tests are skipped by default; run with --codspeed.",
+        allow_module_level=True,
+    )
+
+
+@pytest.mark.timeout(60)
+def test_openapi_dependency_graph(benchmark) -> None:
+    app = create_openapi_app()
+    schema = benchmark(generate_openapi, app)
+    dynamic_paths = [
+        path for path in schema["paths"] if path.startswith(ROUTE_PATH_PREFIX)
+    ]
+    assert len(dynamic_paths) == ROUTE_COUNT
+    assert all(
+        any(
+            parameter["in"] == "query" and parameter["name"] == "query_value"
+            for parameter in schema["paths"][path]["get"]["parameters"]
+        )
+        for path in dynamic_paths
+    )
@@ -0,0 +1,51 @@
+from collections.abc import Callable
+from typing import Annotated, Any
+
+from fastapi import Depends, FastAPI
+
+LAST_DEPENDENCY_INDEX = 100
+ROUTE_COUNT = 20
+ROUTE_PATH_PREFIX = "/openapi-route-"
+
+
+def create_openapi_app() -> FastAPI:
+    app = FastAPI()
+    dependencies: dict[int, Callable[..., Any]] = {}
+
+    def create_dependency(index: int) -> Callable[..., Any]:
+        if index == LAST_DEPENDENCY_INDEX:
+
+            def dependency(query_value: int = index) -> str:
+                return str(query_value)
+
+            dependency.__name__ = f"dependency_{index}"
+            return dependency
+
+        next_dependency = dependencies[index + 1]
+
+        async def dependency(
+            sub_dependency: Annotated[str, Depends(next_dependency)],
+            query_value: int = index,
+        ) -> str:
+            return f"{query_value} -> {sub_dependency}"
+
+        dependency.__name__ = f"dependency_{index}"
+        return dependency
+
+    for index in reversed(range(LAST_DEPENDENCY_INDEX + 1)):
+        dependencies[index] = create_dependency(index)
+
+    async def endpoint(
+        value: Annotated[str, Depends(dependencies[0])],
+    ) -> dict[str, str]:
+        return {"value": value}
+
+    for index in range(ROUTE_COUNT):
+        app.add_api_route(f"{ROUTE_PATH_PREFIX}{index}", endpoint, methods=["GET"])
+
+    return app
+
+
+def generate_openapi(app: FastAPI) -> dict[str, Any]:
+    app.openapi_schema = None
+    return app.openapi()
@@ -0,0 +1,33 @@
+import sys
+
+import pytest
+
+from tests.benchmarks.utils import (
+    ROUTE_COUNT,
+    ROUTE_PATH_PREFIX,
+    create_openapi_app,
+    generate_openapi,
+)
+
+if "--codspeed" not in sys.argv:
+    pytest.skip(
+        "Benchmark tests are skipped by default; run with --codspeed.",
+        allow_module_level=True,
+    )
+
+
+@pytest.mark.timeout(60)
+def test_openapi_dependency_graph(benchmark) -> None:
+    app = create_openapi_app()
+    schema = benchmark(generate_openapi, app)
+    dynamic_paths = [
+        path for path in schema["paths"] if path.startswith(ROUTE_PATH_PREFIX)
+    ]
+    assert len(dynamic_paths) == ROUTE_COUNT
+    assert all(
+        any(
+            parameter["in"] == "query" and parameter["name"] == "query_value"
+            for parameter in schema["paths"][path]["get"]["parameters"]
+        )
+        for path in dynamic_paths
+    )
@@ -0,0 +1,64 @@
+import sys
+from collections.abc import Callable
+from typing import Annotated, Any
+
+import pytest
+from fastapi import Depends, FastAPI
+from fastapi.routing import APIRoute
+
+if "--codspeed" not in sys.argv:
+    pytest.skip(
+        "Benchmark tests are skipped by default; run with --codspeed.",
+        allow_module_level=True,
+    )
+
+LAST_DEPENDENCY_INDEX = 100
+ROUTE_COUNT = 20
+ROUTE_PATH_PREFIX = "/route-"
+
+
+def _create_app() -> FastAPI:
+    app = FastAPI()
+    dependencies: dict[int, Callable[..., Any]] = {}
+
+    def create_dependency(index: int) -> Callable[..., Any]:
+        if index == LAST_DEPENDENCY_INDEX:
+
+            def dependency() -> str:
+                return str(index)
+
+            dependency.__name__ = f"dependency_{index}"
+            return dependency
+
+        next_dependency = dependencies[index + 1]
+
+        async def dependency(
+            sub_dependency: Annotated[str, Depends(next_dependency)],
+        ) -> str:
+            return f"{index} -> {sub_dependency}"
+
+        dependency.__name__ = f"dependency_{index}"
+        return dependency
+
+    for index in reversed(range(LAST_DEPENDENCY_INDEX + 1)):
+        dependencies[index] = create_dependency(index)
+
+    async def endpoint(
+        value: Annotated[str, Depends(dependencies[0])],
+    ) -> dict[str, str]:
+        return {"value": value}
+
+    for index in range(ROUTE_COUNT):
+        app.add_api_route(f"{ROUTE_PATH_PREFIX}{index}", endpoint)
+
+    return app
+
+
+def test_route_dependency_graph(benchmark) -> None:
+    app = benchmark(_create_app)
+    api_routes = [
+        route
+        for route in app.routes
+        if isinstance(route, APIRoute) and route.path.startswith(ROUTE_PATH_PREFIX)
+    ]
+    assert len(api_routes) == ROUTE_COUNT
@@ -1,4 +1,4 @@
-from collections.abc import AsyncGenerator, Generator
+from collections.abc import AsyncGenerator, Callable, Generator
 from typing import Any

 from fastapi.dependencies.models import (
@@ -6,7 +6,6 @@ from fastapi.dependencies.models import (
    _get_cache_key,
    _get_computed_scope,
    _get_oauth_scopes,
-    _get_security_dependencies,
    _get_security_scheme,
    _is_async_gen_callable,
    _is_async_gen_callable_cached,
@@ -93,7 +92,27 @@ def test_callable_classification_is_shared_by_call() -> None:
        cache_info = cached_function.cache_info()
        assert cache_info.hits == 1
        assert cache_info.misses == 1
-        assert cache_info.maxsize == 1024
+        assert cache_info.maxsize == 4096
+
+
+def test_callable_classification_cache_supports_large_apps() -> None:
+    callables: list[Callable[[], None]] = [lambda: None for _ in range(3000)]
+
+    for classifier, cached_classifier in (
+        (_is_gen_callable, _is_gen_callable_cached),
+        (_is_async_gen_callable, _is_async_gen_callable_cached),
+        (_is_coroutine_callable, _is_coroutine_callable_cached),
+    ):
+        cached_classifier.cache_clear()
+
+        for _ in range(2):
+            assert all(not classifier(call) for call in callables)
+
+        cache_info = cached_classifier.cache_info()
+        assert cache_info.hits == len(callables)
+        assert cache_info.misses == len(callables)
+        assert cache_info.maxsize == 4096
+        cached_classifier.cache_clear()


 def test_unhashable_callable_classification() -> None:
@@ -126,7 +145,6 @@ def test_derived_values_are_not_stored_on_dependant() -> None:
    assert _get_oauth_scopes(dependant=dependant) == []
    assert not _uses_scopes(dependant=dependant, cache=uses_scopes_cache)
    assert not _uses_scopes(dependant=dependant, cache=uses_scopes_cache)
-    assert _get_security_dependencies(dependant=dependant) == []
    assert _get_computed_scope(dependant=dependant) is None
    assert _get_cache_key(dependant=dependant) == (async_dependency, (), "")

@@ -140,7 +158,6 @@ def test_security_scheme_helpers() -> None:

    assert _is_security_scheme(dependant=security_dependant)
    assert _get_security_scheme(dependant=security_dependant) is security_scheme
-    assert _get_security_dependencies(dependant=dependant) == [security_dependant]
    assert _uses_scopes(dependant=dependant)


@@ -7,7 +7,15 @@ from typing import Literal

 import anyio
 import pytest
-from fastapi import APIRouter, Depends, FastAPI, HTTPException, Request, WebSocket
+from fastapi import (
+    APIRouter,
+    BackgroundTasks,
+    Depends,
+    FastAPI,
+    HTTPException,
+    Request,
+    WebSocket,
+)
 from fastapi.testclient import TestClient
 from starlette.exceptions import HTTPException as StarletteHTTPException
 from starlette.responses import PlainTextResponse, Response
@@ -491,6 +499,30 @@ def test_app_middleware_still_runs_for_frontend_dependencies(tmp_path: Path):
    assert calls == ["middleware-before", "dependency", "middleware-after"]


+def test_frontend_dependency_response_headers_and_background_tasks(tmp_path: Path):
+    calls: list[str] = []
+
+    def frontend_dependency(
+        response: Response, background_tasks: BackgroundTasks
+    ) -> None:
+        response.headers["X-Frontend-Dependency"] = "applied"
+        response.set_cookie("frontend", "dependency")
+        background_tasks.add_task(calls.append, "background")
+
+    dist = tmp_path / "dist"
+    write_file(dist / "index.html", "app")
+    app = FastAPI(dependencies=[Depends(frontend_dependency)])
+    app.frontend("/", directory=dist)
+
+    response = TestClient(app).get("/")
+
+    assert response.status_code == 200
+    assert response.text == "app"
+    assert response.headers["X-Frontend-Dependency"] == "applied"
+    assert response.cookies["frontend"] == "dependency"
+    assert calls == ["background"]
+
+
 def test_frontend_dependency_validation_errors_return_422(tmp_path: Path):
    def require_token(token: str) -> None:
        pass  # pragma: no cover
@@ -1176,13 +1208,50 @@ def test_check_dir_true_fails_early_for_missing_directory(monkeypatch, tmp_path:
    monkeypatch.chdir(tmp_path)

    with pytest.raises(RuntimeError, match="does not exist") as exc_info:
-        app.frontend("/", directory="missing")
+        app.frontend("/", directory="missing", check_dir=True)

    message = str(exc_info.value)
    assert "'missing'" in message
    assert str(tmp_path / "missing") in message


+def test_check_dir_auto_warns_in_development(monkeypatch, tmp_path: Path):
+    monkeypatch.setenv("FASTAPI_ENV", "development")
+    app = FastAPI()
+
+    with pytest.warns(UserWarning, match="does not exist") as warnings:
+        app.frontend("/", directory=tmp_path / "missing")
+
+    assert str(tmp_path / "missing") in str(warnings[0].message)
+    assert warnings[0].filename == __file__
+
+
+def test_check_dir_auto_router_warning_points_to_user_code(monkeypatch, tmp_path: Path):
+    monkeypatch.setenv("FASTAPI_ENV", "development")
+    router = APIRouter()
+
+    with pytest.warns(UserWarning, match="does not exist") as warnings:
+        router.frontend("/", directory=tmp_path / "missing")
+
+    assert warnings[0].filename == __file__
+
+
+def test_check_dir_true_fails_in_development(monkeypatch, tmp_path: Path):
+    monkeypatch.setenv("FASTAPI_ENV", "development")
+    app = FastAPI()
+
+    with pytest.raises(RuntimeError, match="does not exist"):
+        app.frontend("/", directory=tmp_path / "missing", check_dir=True)
+
+
+def test_check_dir_auto_fails_outside_development(monkeypatch, tmp_path: Path):
+    monkeypatch.setenv("FASTAPI_ENV", "production")
+    router = APIRouter()
+
+    with pytest.raises(RuntimeError, match="does not exist"):
+        router.frontend("/", directory=tmp_path / "missing")
+
+
 def test_check_dir_false_allows_missing_directory_and_fails_on_request(tmp_path: Path):
    app = FastAPI()
    app.frontend("/", directory=tmp_path / "missing", check_dir=False)
@@ -202,6 +202,20 @@ def test_encode_model_with_default():
    }


+def test_encode_model_with_default_in_dict_and_list():
+    model = ModelWithDefault(foo="foo", bar="bar")
+    assert jsonable_encoder([model], exclude_defaults=True) == [{"foo": "foo"}]
+    assert jsonable_encoder({"key": model}, exclude_defaults=True) == {
+        "key": {"foo": "foo"}
+    }
+    assert jsonable_encoder({"key": [model]}, exclude_defaults=True) == {
+        "key": [{"foo": "foo"}]
+    }
+    assert jsonable_encoder({"key": model}) == {
+        "key": {"foo": "foo", "bar": "bar", "bla": "bla"}
+    }
+
+
 def test_custom_encoders():
    class safe_datetime(datetime):
        pass
@@ -0,0 +1,143 @@
+from typing import Annotated
+
+from dirty_equals import IsList
+from fastapi import FastAPI, Query
+from fastapi.testclient import TestClient
+from inline_snapshot import snapshot
+from pydantic import Field
+
+MaxSizedSet = Annotated[set[str], Field(max_length=3)]
+
+app = FastAPI()
+
+
+@app.get("/")
+def read_root(foo: Annotated[MaxSizedSet | None, Query()] = None):
+    return {"foo": foo}
+
+
+client = TestClient(app)
+
+
+def test_endpoint_none():
+    response = client.get("/")
+    assert response.status_code == 200
+    assert response.json() == {"foo": None}
+
+
+def test_endpoint_valid():
+    response = client.get("/", params={"foo": ["a", "b"]})
+    assert response.status_code == 200
+    assert response.json() == {"foo": IsList("a", "b", check_order=False)}
+
+
+def test_endpoint_too_long():
+    response = client.get("/", params={"foo": ["a", "b", "c", "d"]})
+    assert response.status_code == 422
+    assert response.json() == snapshot(
+        {
+            "detail": [
+                {
+                    "type": "too_long",
+                    "loc": ["query", "foo"],
+                    "msg": "Set should have at most 3 items after validation, not more",
+                    "input": IsList("a", "b", "c", "d", check_order=False),
+                    "ctx": {
+                        "actual_length": None,
+                        "field_type": "Set",
+                        "max_length": 3,
+                    },
+                }
+            ]
+        }
+    )
+
+
+def test_openapi():
+    assert app.openapi() == snapshot(
+        {
+            "components": {
+                "schemas": {
+                    "HTTPValidationError": {
+                        "properties": {
+                            "detail": {
+                                "items": {
+                                    "$ref": "#/components/schemas/ValidationError"
+                                },
+                                "title": "Detail",
+                                "type": "array",
+                            },
+                        },
+                        "title": "HTTPValidationError",
+                        "type": "object",
+                    },
+                    "ValidationError": {
+                        "properties": {
+                            "ctx": {"title": "Context", "type": "object"},
+                            "input": {"title": "Input"},
+                            "loc": {
+                                "items": {
+                                    "anyOf": [{"type": "string"}, {"type": "integer"}],
+                                },
+                                "title": "Location",
+                                "type": "array",
+                            },
+                            "msg": {"title": "Message", "type": "string"},
+                            "type": {"title": "Error Type", "type": "string"},
+                        },
+                        "required": ["loc", "msg", "type"],
+                        "title": "ValidationError",
+                        "type": "object",
+                    },
+                },
+            },
+            "info": {
+                "title": "FastAPI",
+                "version": "0.1.0",
+            },
+            "openapi": "3.1.0",
+            "paths": {
+                "/": {
+                    "get": {
+                        "operationId": "read_root__get",
+                        "parameters": [
+                            {
+                                "in": "query",
+                                "name": "foo",
+                                "required": False,
+                                "schema": {
+                                    "anyOf": [
+                                        {
+                                            "items": {"type": "string"},
+                                            "maxItems": 3,
+                                            "type": "array",
+                                            "uniqueItems": True,
+                                        },
+                                        {"type": "null"},
+                                    ],
+                                    "title": "Foo",
+                                },
+                            },
+                        ],
+                        "responses": {
+                            "200": {
+                                "content": {"application/json": {"schema": {}}},
+                                "description": "Successful Response",
+                            },
+                            "422": {
+                                "content": {
+                                    "application/json": {
+                                        "schema": {
+                                            "$ref": "#/components/schemas/HTTPValidationError",
+                                        },
+                                    },
+                                },
+                                "description": "Validation Error",
+                            },
+                        },
+                        "summary": "Read Root",
+                    },
+                },
+            },
+        }
+    )
@@ -1,3 +1,5 @@
+from collections.abc import Iterable
+
 from fastapi import FastAPI
 from fastapi.testclient import TestClient
 from pydantic import BaseModel
@@ -65,6 +67,21 @@ def get_exclude_unset_none() -> ModelDefaults:
    return ModelDefaults(x=None, y="y")


+@app.get("/iterable_exclude_unset", response_model_exclude_unset=True)
+def get_iterable_exclude_unset() -> Iterable[ModelDefaults]:
+    return [ModelDefaults(x=None, y="y")]
+
+
+@app.get("/iterable_exclude_defaults", response_model_exclude_defaults=True)
+def get_iterable_exclude_defaults() -> Iterable[ModelDefaults]:
+    return [ModelDefaults(x=None, y="y")]
+
+
+@app.get("/iterable_exclude_none", response_model_exclude_none=True)
+def get_iterable_exclude_none() -> Iterable[ModelDefaults]:
+    return [ModelDefaults(x=None, y="y")]
+
+
 client = TestClient(app)


@@ -91,3 +108,18 @@ def test_return_exclude_none():
 def test_return_exclude_unset_none():
    response = client.get("/exclude_unset_none")
    assert response.json() == {"y": "y"}
+
+
+def test_return_iterable_exclude_unset():
+    response = client.get("/iterable_exclude_unset")
+    assert response.json() == [{"x": None, "y": "y"}]
+
+
+def test_return_iterable_exclude_defaults():
+    response = client.get("/iterable_exclude_defaults")
+    assert response.json() == [{}]
+
+
+def test_return_iterable_exclude_none():
+    response = client.get("/iterable_exclude_none")
+    assert response.json() == [{"y": "y", "z": "z"}]
@@ -6,7 +6,7 @@ import fastapi.routing
 import pytest
 from fastapi import APIRouter, FastAPI
 from fastapi.responses import EventSourceResponse
-from fastapi.sse import ServerSentEvent
+from fastapi.sse import ServerSentEvent, format_sse_event
 from fastapi.testclient import TestClient
 from pydantic import BaseModel

@@ -64,7 +64,8 @@ async def sse_items_event():

@app.get("/items/stream-mixed", response_class=EventSourceResponse)
 async def sse_items_mixed() -> AsyncIterable[Item]:
-    yield items[0]
+    for item in items:
+        yield item
    yield ServerSentEvent(data="custom-event", event="special")
    yield items[1]

@@ -96,6 +97,12 @@ async def stream_events():
    yield {"msg": "world"}


+@router.get("/events-typed", response_class=EventSourceResponse)
+async def stream_events_typed() -> AsyncIterable[Item]:
+    for item in items:
+        yield item
+
+
 app.include_router(router, prefix="/api")


@@ -274,6 +281,45 @@ def test_sse_on_router_included_in_app(client: TestClient):
    assert len(data_lines) == 2


+def test_sse_router_typed_stream(client: TestClient):
+    response = client.get("/api/events-typed")
+    assert response.status_code == 200
+    assert response.headers["content-type"] == "text/event-stream; charset=utf-8"
+    data_lines = [
+        line for line in response.text.strip().split("\n") if line.startswith("data: ")
+    ]
+    assert len(data_lines) == 3
+
+
+def test_sse_router_typed_openapi_schema(client: TestClient):
+    """Typed SSE endpoint on a router should preserve itemSchema with contentSchema."""
+    response = client.get("/openapi.json")
+    assert response.status_code == 200
+    paths = response.json()["paths"]
+    sse_response = paths["/api/events-typed"]["get"]["responses"]["200"]
+    assert sse_response == {
+        "description": "Successful Response",
+        "content": {
+            "text/event-stream": {
+                "itemSchema": {
+                    "type": "object",
+                    "properties": {
+                        "data": {
+                            "type": "string",
+                            "contentMediaType": "application/json",
+                            "contentSchema": {"$ref": "#/components/schemas/Item"},
+                        },
+                        "event": {"type": "string"},
+                        "id": {"type": "string"},
+                        "retry": {"type": "integer", "minimum": 0},
+                    },
+                    "required": ["data"],
+                }
+            }
+        },
+    }
+
+
 # Keepalive ping tests


@@ -325,3 +371,120 @@ def test_no_keepalive_when_fast(client: TestClient):
    assert response.status_code == 200
    # KEEPALIVE_COMMENT is ": ping\n\n".
    assert ": ping\n" not in response.text
+
+
+@pytest.mark.parametrize(
+    ("data", "expected_result"),
+    [
+        ("Hello\n", b"data: Hello\ndata: \n\n"),
+        ("Hello\n\n", b"data: Hello\ndata: \ndata: \n\n"),
+        ("\n", b"data: \ndata: \n\n"),
+        ("Hello\r\nWorld", b"data: Hello\ndata: World\n\n"),
+        ("Hello\rWorld", b"data: Hello\ndata: World\n\n"),
+        ("A\u2028B", "data: A\u2028B\n\n".encode()),
+        ("A\vB", b"data: A\x0bB\n\n"),
+        ("", b"data: \n\n"),
+    ],
+)
+def test_format_sse_event_splitlines_behavior_in_data(
+    data: str, expected_result: bytes
+) -> None:
+    assert format_sse_event(data_str=data) == expected_result
+
+
+def test_format_sse_event_splitlines_behavior_in_comment():
+    assert format_sse_event(comment="hi\n") == b": hi\n: \n\n"
+
+
+# default_response_class tests
+
+
+sse_schema_response = {
+    "description": "Successful Response",
+    "content": {
+        "text/event-stream": {
+            "itemSchema": {
+                "type": "object",
+                "properties": {
+                    "data": {
+                        "type": "string",
+                        "contentMediaType": "application/json",
+                        "contentSchema": {"$ref": "#/components/schemas/Item"},
+                    },
+                    "event": {"type": "string"},
+                    "id": {"type": "string"},
+                    "retry": {"type": "integer", "minimum": 0},
+                },
+                "required": ["data"],
+            }
+        }
+    },
+}
+
+
+# default_response_class on app
+
+default_app_app = FastAPI(default_response_class=EventSourceResponse)
+default_app_router = APIRouter()
+
+
+@default_app_router.get("/stream")
+async def default_app_stream() -> AsyncIterable[Item]:
+    for item in items:
+        yield item
+
+
+default_app_app.include_router(default_app_router, prefix="/api")
+
+
+def test_default_response_class_on_app_stream():
+    with TestClient(default_app_app) as client:
+        response = client.get("/api/stream")
+    assert response.status_code == 200
+    assert response.headers["content-type"] == "text/event-stream; charset=utf-8"
+    data_lines = [
+        line for line in response.text.strip().split("\n") if line.startswith("data: ")
+    ]
+    assert len(data_lines) == 3
+
+
+def test_default_response_class_on_app_openapi_schema():
+    assert (
+        default_app_app.openapi()["paths"]["/api/stream"]["get"]["responses"]["200"]
+        == sse_schema_response
+    )
+
+
+# default_response_class on parent router
+
+default_parent_app = FastAPI()
+parent_router = APIRouter(default_response_class=EventSourceResponse)
+child_router = APIRouter()
+
+
+@child_router.get("/stream")
+async def default_parent_stream() -> AsyncIterable[Item]:
+    for item in items:
+        yield item
+
+
+parent_router.include_router(child_router)
+default_parent_app.include_router(parent_router, prefix="/api")
+
+
+def test_default_response_class_on_parent_router_stream():
+    with TestClient(default_parent_app) as client:
+        response = client.get("/api/stream")
+    assert response.status_code == 200
+    assert response.headers["content-type"] == "text/event-stream; charset=utf-8"
+    data_lines = [
+        line for line in response.text.strip().split("\n") if line.startswith("data: ")
+    ]
+    assert len(data_lines) == 3
+
+
+def test_default_response_class_on_parent_router_openapi_schema():
+    assert (
+        default_parent_app.openapi()["paths"]["/api/stream"]["get"]["responses"]["200"]
+        == sse_schema_response
+    )
@@ -1,13 +1,14 @@
 import json
 from typing import AsyncIterable, Iterable  # noqa: UP035 to test coverage

-from fastapi import FastAPI
+from fastapi import APIRouter, FastAPI
 from fastapi.testclient import TestClient
 from pydantic import BaseModel


 class Item(BaseModel):
    name: str
+    optional: str | None = None


 app = FastAPI()
@@ -23,6 +24,16 @@ def stream_bare_sync() -> Iterable:
    yield {"name": "bar"}


+router = APIRouter()
+
+
+@router.get("/events-jsonl", response_model_exclude_none=True)
+async def stream_events_jsonl() -> AsyncIterable[Item]:
+    yield Item(name="foo")
+
+
+app.include_router(router, prefix="/api")
+
 client = TestClient(app)


@@ -40,3 +51,24 @@ def test_stream_bare_sync_iterable():
    assert response.headers["content-type"] == "application/jsonl"
    lines = [json.loads(line) for line in response.text.strip().splitlines()]
    assert lines == [{"name": "bar"}]
+
+
+def test_jsonl_router_typed_stream():
+    response = client.get("/api/events-jsonl")
+    assert response.status_code == 200
+    assert response.headers["content-type"] == "application/jsonl"
+    lines = [json.loads(line) for line in response.text.strip().splitlines()]
+    assert lines == [{"name": "foo"}]
+
+
+def test_jsonl_router_typed_openapi_schema():
+    response = client.get("/openapi.json")
+    assert response.status_code == 200
+    paths = response.json()["paths"]
+    jsonl_response = paths["/api/events-jsonl"]["get"]["responses"]["200"]
+    assert jsonl_response == {
+        "description": "Successful Response",
+        "content": {
+            "application/jsonl": {"itemSchema": {"$ref": "#/components/schemas/Item"}}
+        },
+    }
@@ -0,0 +1,452 @@
+from collections.abc import AsyncIterable
+
+import pytest
+from fastapi import Depends, FastAPI, Response
+from fastapi.responses import EventSourceResponse, StreamingResponse
+from fastapi.testclient import TestClient
+from inline_snapshot import snapshot
+
+SSE_RESPONSE = {
+    "description": "Successful Response",
+    "content": {
+        "text/event-stream": {
+            "itemSchema": {
+                "type": "object",
+                "properties": {
+                    "data": {
+                        "type": "string",
+                        "contentMediaType": "application/json",
+                        "contentSchema": {
+                            "type": "object",
+                            "additionalProperties": {"type": "string"},
+                            "title": "SSE stream item",
+                        },
+                    },
+                    "event": {"type": "string"},
+                    "id": {"type": "string"},
+                    "retry": {"type": "integer", "minimum": 0},
+                },
+                "required": ["data"],
+            }
+        }
+    },
+}
+
+JSONL_RESPONSE = {
+    "description": "Successful Response",
+    "content": {
+        "application/jsonl": {
+            "itemSchema": {
+                "type": "object",
+                "additionalProperties": {"type": "string"},
+                "title": "JSONL stream item",
+            }
+        }
+    },
+}
+
+
+app = FastAPI()
+
+
+def set_accepted(response: Response) -> None:
+    response.status_code = 202
+
+
+@app.post("/sse", response_class=EventSourceResponse, status_code=201)
+async def sse() -> AsyncIterable[dict[str, str]]:
+    yield {"message": "created"}
+
+
+@app.post("/jsonl", status_code=201)
+async def jsonl() -> AsyncIterable[dict[str, str]]:
+    yield {"message": "created"}
+
+
+@app.post("/raw", response_class=StreamingResponse, status_code=201)
+async def raw() -> AsyncIterable[str]:
+    yield "accepted"
+
+
+@app.post(
+    "/sse-dependency",
+    response_class=EventSourceResponse,
+    responses={202: SSE_RESPONSE},
+)
+async def sse_dependency(
+    accepted: None = Depends(set_accepted),
+) -> AsyncIterable[dict[str, str]]:
+    yield {"message": "accepted"}
+
+
+@app.post("/jsonl-dependency", responses={202: JSONL_RESPONSE})
+async def jsonl_dependency(
+    accepted: None = Depends(set_accepted),
+) -> AsyncIterable[dict[str, str]]:
+    yield {"message": "accepted"}
+
+
+@app.post(
+    "/raw-dependency",
+    response_class=StreamingResponse,
+    responses={202: {"description": "Accepted"}},
+)
+async def raw_dependency(
+    accepted: None = Depends(set_accepted),
+) -> AsyncIterable[str]:
+    yield "accepted"
+
+
+@app.post(
+    "/sse-dependency-override",
+    response_class=EventSourceResponse,
+    status_code=201,
+    responses={202: SSE_RESPONSE},
+)
+async def sse_dependency_override(
+    accepted: None = Depends(set_accepted),
+) -> AsyncIterable[dict[str, str]]:
+    yield {"message": "overridden"}
+
+
+@app.post(
+    "/jsonl-dependency-override",
+    status_code=201,
+    responses={202: JSONL_RESPONSE},
+)
+async def jsonl_dependency_override(
+    accepted: None = Depends(set_accepted),
+) -> AsyncIterable[dict[str, str]]:
+    yield {"message": "overridden"}
+
+
+@app.post(
+    "/raw-dependency-override",
+    response_class=StreamingResponse,
+    status_code=201,
+    responses={202: {"description": "Accepted"}},
+)
+async def raw_dependency_override(
+    accepted: None = Depends(set_accepted),
+) -> AsyncIterable[str]:
+    yield "overridden"
+
+
+client = TestClient(app)
+
+
+@pytest.mark.parametrize(
+    "path,expected_status_code",
+    [
+        ("/sse", 201),
+        ("/jsonl", 201),
+        ("/raw", 201),
+        ("/sse-dependency", 202),
+        ("/jsonl-dependency", 202),
+        ("/raw-dependency", 202),
+        ("/sse-dependency-override", 202),
+        ("/jsonl-dependency-override", 202),
+        ("/raw-dependency-override", 202),
+    ],
+)
+def test_status_code(path: str, expected_status_code: int) -> None:
+    response = client.post(path)
+    assert response.status_code == expected_status_code
+
+
+def test_openapi() -> None:
+    openapi = app.openapi()
+
+    assert openapi == snapshot(
+        {
+            "openapi": "3.1.0",
+            "info": {"title": "FastAPI", "version": "0.1.0"},
+            "paths": {
+                "/sse": {
+                    "post": {
+                        "summary": "Sse",
+                        "operationId": "sse_sse_post",
+                        "responses": {
+                            "201": {
+                                "description": "Successful Response",
+                                "content": {
+                                    "text/event-stream": {
+                                        "itemSchema": {
+                                            "type": "object",
+                                            "properties": {
+                                                "data": {
+                                                    "type": "string",
+                                                    "contentMediaType": "application/json",
+                                                    "contentSchema": {
+                                                        "type": "object",
+                                                        "additionalProperties": {
+                                                            "type": "string"
+                                                        },
+                                                        "title": "Streamitem Sse Sse Post",
+                                                    },
+                                                },
+                                                "event": {"type": "string"},
+                                                "id": {"type": "string"},
+                                                "retry": {
+                                                    "type": "integer",
+                                                    "minimum": 0,
+                                                },
+                                            },
+                                            "required": ["data"],
+                                        }
+                                    }
+                                },
+                            }
+                        },
+                    }
+                },
+                "/jsonl": {
+                    "post": {
+                        "summary": "Jsonl",
+                        "operationId": "jsonl_jsonl_post",
+                        "responses": {
+                            "201": {
+                                "description": "Successful Response",
+                                "content": {
+                                    "application/jsonl": {
+                                        "itemSchema": {
+                                            "type": "object",
+                                            "additionalProperties": {"type": "string"},
+                                            "title": "Streamitem Jsonl Jsonl Post",
+                                        }
+                                    }
+                                },
+                            }
+                        },
+                    }
+                },
+                "/raw": {
+                    "post": {
+                        "summary": "Raw",
+                        "operationId": "raw_raw_post",
+                        "responses": {"201": {"description": "Successful Response"}},
+                    }
+                },
+                "/sse-dependency": {
+                    "post": {
+                        "summary": "Sse Dependency",
+                        "operationId": "sse_dependency_sse_dependency_post",
+                        "responses": {
+                            "200": {
+                                "description": "Successful Response",
+                                "content": {
+                                    "text/event-stream": {
+                                        "itemSchema": {
+                                            "type": "object",
+                                            "properties": {
+                                                "data": {
+                                                    "type": "string",
+                                                    "contentMediaType": "application/json",
+                                                    "contentSchema": {
+                                                        "type": "object",
+                                                        "additionalProperties": {
+                                                            "type": "string"
+                                                        },
+                                                        "title": "Streamitem Sse Dependency Sse Dependency Post",
+                                                    },
+                                                },
+                                                "event": {"type": "string"},
+                                                "id": {"type": "string"},
+                                                "retry": {
+                                                    "type": "integer",
+                                                    "minimum": 0,
+                                                },
+                                            },
+                                            "required": ["data"],
+                                        }
+                                    }
+                                },
+                            },
+                            "202": {
+                                "description": "Successful Response",
+                                "content": {
+                                    "text/event-stream": {
+                                        "itemSchema": {
+                                            "type": "object",
+                                            "properties": {
+                                                "data": {
+                                                    "type": "string",
+                                                    "contentMediaType": "application/json",
+                                                    "contentSchema": {
+                                                        "type": "object",
+                                                        "additionalProperties": {
+                                                            "type": "string"
+                                                        },
+                                                        "title": "SSE stream item",
+                                                    },
+                                                },
+                                                "event": {"type": "string"},
+                                                "id": {"type": "string"},
+                                                "retry": {
+                                                    "type": "integer",
+                                                    "minimum": 0,
+                                                },
+                                            },
+                                            "required": ["data"],
+                                        }
+                                    }
+                                },
+                            },
+                        },
+                    }
+                },
+                "/jsonl-dependency": {
+                    "post": {
+                        "summary": "Jsonl Dependency",
+                        "operationId": "jsonl_dependency_jsonl_dependency_post",
+                        "responses": {
+                            "200": {
+                                "description": "Successful Response",
+                                "content": {
+                                    "application/jsonl": {
+                                        "itemSchema": {
+                                            "type": "object",
+                                            "additionalProperties": {"type": "string"},
+                                            "title": "Streamitem Jsonl Dependency Jsonl Dependency Post",
+                                        }
+                                    }
+                                },
+                            },
+                            "202": {
+                                "description": "Successful Response",
+                                "content": {
+                                    "application/jsonl": {
+                                        "itemSchema": {
+                                            "type": "object",
+                                            "additionalProperties": {"type": "string"},
+                                            "title": "JSONL stream item",
+                                        }
+                                    }
+                                },
+                            },
+                        },
+                    }
+                },
+                "/raw-dependency": {
+                    "post": {
+                        "summary": "Raw Dependency",
+                        "operationId": "raw_dependency_raw_dependency_post",
+                        "responses": {
+                            "200": {"description": "Successful Response"},
+                            "202": {"description": "Accepted"},
+                        },
+                    }
+                },
+                "/sse-dependency-override": {
+                    "post": {
+                        "summary": "Sse Dependency Override",
+                        "operationId": "sse_dependency_override_sse_dependency_override_post",
+                        "responses": {
+                            "201": {
+                                "description": "Successful Response",
+                                "content": {
+                                    "text/event-stream": {
+                                        "itemSchema": {
+                                            "type": "object",
+                                            "properties": {
+                                                "data": {
+                                                    "type": "string",
+                                                    "contentMediaType": "application/json",
+                                                    "contentSchema": {
+                                                        "type": "object",
+                                                        "additionalProperties": {
+                                                            "type": "string"
+                                                        },
+                                                        "title": "Streamitem Sse Dependency Override Sse Dependency Override Post",
+                                                    },
+                                                },
+                                                "event": {"type": "string"},
+                                                "id": {"type": "string"},
+                                                "retry": {
+                                                    "type": "integer",
+                                                    "minimum": 0,
+                                                },
+                                            },
+                                            "required": ["data"],
+                                        }
+                                    }
+                                },
+                            },
+                            "202": {
+                                "description": "Successful Response",
+                                "content": {
+                                    "text/event-stream": {
+                                        "itemSchema": {
+                                            "type": "object",
+                                            "properties": {
+                                                "data": {
+                                                    "type": "string",
+                                                    "contentMediaType": "application/json",
+                                                    "contentSchema": {
+                                                        "type": "object",
+                                                        "additionalProperties": {
+                                                            "type": "string"
+                                                        },
+                                                        "title": "SSE stream item",
+                                                    },
+                                                },
+                                                "event": {"type": "string"},
+                                                "id": {"type": "string"},
+                                                "retry": {
+                                                    "type": "integer",
+                                                    "minimum": 0,
+                                                },
+                                            },
+                                            "required": ["data"],
+                                        }
+                                    }
+                                },
+                            },
+                        },
+                    }
+                },
+                "/jsonl-dependency-override": {
+                    "post": {
+                        "summary": "Jsonl Dependency Override",
+                        "operationId": "jsonl_dependency_override_jsonl_dependency_override_post",
+                        "responses": {
+                            "201": {
+                                "description": "Successful Response",
+                                "content": {
+                                    "application/jsonl": {
+                                        "itemSchema": {
+                                            "type": "object",
+                                            "additionalProperties": {"type": "string"},
+                                            "title": "Streamitem Jsonl Dependency Override Jsonl Dependency Override Post",
+                                        }
+                                    }
+                                },
+                            },
+                            "202": {
+                                "description": "Successful Response",
+                                "content": {
+                                    "application/jsonl": {
+                                        "itemSchema": {
+                                            "type": "object",
+                                            "additionalProperties": {"type": "string"},
+                                            "title": "JSONL stream item",
+                                        }
+                                    }
+                                },
+                            },
+                        },
+                    }
+                },
+                "/raw-dependency-override": {
+                    "post": {
+                        "summary": "Raw Dependency Override",
+                        "operationId": "raw_dependency_override_raw_dependency_override_post",
+                        "responses": {
+                            "201": {"description": "Successful Response"},
+                            "202": {"description": "Accepted"},
+                        },
+                    }
+                },
+            },
+        }
+    )
@@ -1005,9 +1005,9 @@ requires-dist = [
    { name = "email-validator", marker = "extra == 'all'", specifier = ">=2.0.0" },
    { name = "email-validator", marker = "extra == 'standard'", specifier = ">=2.0.0" },
    { name = "email-validator", marker = "extra == 'standard-no-fastapi-cloud-cli'", specifier = ">=2.0.0" },
-    { name = "fastapi-cli", extras = ["standard"], marker = "extra == 'all'", specifier = ">=0.0.8" },
-    { name = "fastapi-cli", extras = ["standard"], marker = "extra == 'standard'", specifier = ">=0.0.8" },
-    { name = "fastapi-cli", extras = ["standard-no-fastapi-cloud-cli"], marker = "extra == 'standard-no-fastapi-cloud-cli'", specifier = ">=0.0.8" },
+    { name = "fastapi-cli", extras = ["standard"], marker = "extra == 'all'", specifier = ">=0.0.32" },
+    { name = "fastapi-cli", extras = ["standard"], marker = "extra == 'standard'", specifier = ">=0.0.32" },
+    { name = "fastapi-cli", extras = ["standard-no-fastapi-cloud-cli"], marker = "extra == 'standard-no-fastapi-cloud-cli'", specifier = ">=0.0.32" },
    { name = "fastar", marker = "extra == 'standard'", specifier = ">=0.9.0" },
    { name = "httpx", marker = "extra == 'all'", specifier = ">=0.23.0,<1.0.0" },
    { name = "httpx", marker = "extra == 'standard'", specifier = ">=0.23.0,<1.0.0" },
@@ -1144,7 +1144,7 @@ translations = [

 [[package]]
 name = "fastapi-cli"
-version = "0.0.20"
+version = "0.0.32"
 source = { registry = "https://pypi.org/simple" }
 dependencies = [
    { name = "rich-toolkit" },
@@ -1152,9 +1152,9 @@ dependencies = [
    { name = "typer" },
    { name = "uvicorn", extra = ["standard"] },
 ]
-sdist = { url = "https://files.pythonhosted.org/packages/d3/ca/d90fb3bfbcbd6e56c77afd9d114dd6ce8955d8bb90094399d1c70e659e40/fastapi_cli-0.0.20.tar.gz", hash = "sha256:d17c2634f7b96b6b560bc16b0035ed047d523c912011395f49f00a421692bc3a", size = 19786, upload-time = "2025-12-22T17:13:33.794Z" }
+sdist = { url = "https://files.pythonhosted.org/packages/33/eb/3b534c6f8e157f9ddbf2a153512307c886cad0b258739c200dd8ff8c4452/fastapi_cli-0.0.32.tar.gz", hash = "sha256:38024d2345275e1b37ce8848727a580d84901b570e96b3256d9d36a9a5039424", size = 26636, upload-time = "2026-07-16T12:16:58.678Z" }
 wheels = [
-    { url = "https://files.pythonhosted.org/packages/08/89/5c4eef60524d0fd704eb0706885b82cd5623a43396b94e4a5b17d3a3f516/fastapi_cli-0.0.20-py3-none-any.whl", hash = "sha256:e58b6a0038c0b1532b7a0af690656093dee666201b6b19d3c87175b358e9f783", size = 12390, upload-time = "2025-12-22T17:13:31.708Z" },
+    { url = "https://files.pythonhosted.org/packages/d5/53/56ae5ae17bb0a5d89d1d31e5320eb1865553ebbfbde91cdc4c221245f2a8/fastapi_cli-0.0.32-py3-none-any.whl", hash = "sha256:8dcc286fa32f01bbd3f65dd09cfd5a2540ed5f2230b77db7fd30978d6165f3c4", size = 14670, upload-time = "2026-07-16T12:16:57.297Z" },
 ]

 [package.optional-dependencies]
@@ -1384,14 +1384,14 @@ wheels = [

 [[package]]
 name = "gitpython"
-version = "3.1.50"
+version = "3.1.54"
 source = { registry = "https://pypi.org/simple" }
 dependencies = [
    { name = "gitdb" },
 ]
-sdist = { url = "https://files.pythonhosted.org/packages/33/f6/354ae6491228b5eb40e10d89c4d13c651fe1cf7556e35ebdded50cff57ce/gitpython-3.1.50.tar.gz", hash = "sha256:80da2d12504d52e1f998772dc5baf6e553f8d2fcfe1fcc226c9d9a2ee3372dcc", size = 219798, upload-time = "2026-05-06T04:01:26.571Z" }
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 [[package]]
Author	SHA1	Message	Date
Sebastián Ramírezandgithub-actions[bot]	95f8322ee1	🔖 Release version 0.141.1 (#16106 ) Co-authored-by: github-actions[bot] <github-actions[bot]@users.noreply.github.com>	2026-07-29 17:15:38 +00:00
github-actions[bot]	f137944c43	📝 Update release notes [skip ci]	2026-07-29 17:05:15 +00:00
Sebastián Ramírez	d62354434b	🐛 Fix support for background tasks and headers from dependencies in `app.frontend()` (#16105 )	2026-07-29 19:04:36 +02:00
github-actions[bot]	1d211b9c10	📝 Update release notes [skip ci]	2026-07-29 15:32:23 +00:00
Sebastián Ramírez	8a1f876841	📝 Document `FASTAPI_ENV` in FastAPI CLI guide (#16104 )	2026-07-29 17:27:41 +02:00
Sebastián Ramírezandgithub-actions[bot]	c7e7b651d6	🔖 Release version 0.141.0 (#16103 ) Co-authored-by: github-actions[bot] <github-actions[bot]@users.noreply.github.com>	2026-07-29 14:45:21 +00:00
github-actions[bot]	6bceb84053	📝 Update release notes [skip ci]	2026-07-29 14:32:16 +00:00
Sebastián Ramírez	5429fed84e	✨ Add `app.frontend(check_dir="auto")`, to make local development more convenient with `fastapi dev` (#16102 )	2026-07-29 16:31:28 +02:00
Sebastián Ramírezandgithub-actions[bot]	628663f4f8	🔖 Release version 0.140.13 (#16096 ) Co-authored-by: github-actions[bot] <github-actions[bot]@users.noreply.github.com>	2026-07-28 15:34:37 +00:00
github-actions[bot]	0b54fd0027	📝 Update release notes [skip ci]	2026-07-28 15:25:56 +00:00
Saurabh Vijay Salve pre-commit-ci-lite[bot]Yurii Motov	e92a0dc3ce	🐛 Fix `status_code` being ignored for SSE and JSONL streaming endpoints (#15937 ) Co-authored-by: pre-commit-ci-lite[bot] <117423508+pre-commit-ci-lite[bot]@users.noreply.github.com> Co-authored-by: Yurii Motov <yurii.motov.monte@gmail.com>	2026-07-28 17:25:12 +02:00
github-actions[bot]	6215d8a6f3	📝 Update release notes [skip ci]	2026-07-28 15:15:44 +00:00
AshNicolus Yurii Motov Sebastián Ramírez	12242c4fba	📝 Fix `format_sse_event` docstring rendering of `\n\n` terminator (#15613 ) Co-authored-by: Yurii Motov <109919500+YuriiMotov@users.noreply.github.com> Co-authored-by: Sebastián Ramírez <tiangolo@gmail.com>	2026-07-28 15:14:58 +00:00
github-actions[bot]	70a8f3dd03	📝 Update release notes [skip ci]	2026-07-28 15:09:33 +00:00
Saurabh Vijay SalveandCursor	4f0152c028	📝 Add API reference page for fastapi.sse (#15930 ) Co-authored-by: Cursor <cursoragent@cursor.com>	2026-07-28 17:08:21 +02:00
Sebastián Ramírezandgithub-actions[bot]	5f255058f4	🔖 Release version 0.140.12 (#16095 ) Co-authored-by: github-actions[bot] <github-actions[bot]@users.noreply.github.com>	2026-07-28 15:04:01 +00:00
github-actions[bot]	76e2c833b5	📝 Update release notes [skip ci]	2026-07-28 14:55:27 +00:00
Zawwar Sami pre-commit-ci-lite[bot]Yurii Motov Sebastián Ramírez	0f3e7bd682	🐛 Fix line splitting in `format_sse_event` to comply with SSE spec (#15515 ) Co-authored-by: pre-commit-ci-lite[bot] <117423508+pre-commit-ci-lite[bot]@users.noreply.github.com> Co-authored-by: Yurii Motov <109919500+YuriiMotov@users.noreply.github.com> Co-authored-by: Sebastián Ramírez <tiangolo@gmail.com>	2026-07-28 16:54:54 +02:00
Sebastián Ramírezandgithub-actions[bot]	31ce3cb8d7	🔖 Release version 0.140.11 (#16094 ) Co-authored-by: github-actions[bot] <github-actions[bot]@users.noreply.github.com>	2026-07-28 14:31:44 +00:00
github-actions[bot]	4a01c7f1a5	📝 Update release notes [skip ci]	2026-07-28 14:23:09 +00:00
Yurii MotovandSebastián Ramírez	d6537f774b	🐛 Fix `response_model_*` params ignored for non-generator endpoints with `Iterable[..]` return type (#15093 ) Co-authored-by: Sebastián Ramírez <tiangolo@gmail.com>	2026-07-28 16:22:05 +02:00
Sebastián Ramírezandgithub-actions[bot]	0f3d3b2f9f	🔖 Release version 0.140.10 (#16093 ) Co-authored-by: github-actions[bot] <github-actions[bot]@users.noreply.github.com>	2026-07-28 16:19:13 +02:00
github-actions[bot]	584efa0981	📝 Update release notes [skip ci]	2026-07-28 14:04:58 +00:00
Yurii MotovandSebastián Ramírez	65e42bd5ec	🐛 Fix handling sequences with nested Annotated types (#14874 ) Co-authored-by: Sebastián Ramírez <tiangolo@gmail.com>	2026-07-28 16:04:16 +02:00
github-actions[bot]	9db320278c	📝 Update release notes [skip ci]	2026-07-28 13:48:40 +00:00
Sebastián Ramírez	d3cd6054e4	🐛 Accept any base test failure as regression (#16092 )	2026-07-28 13:47:58 +00:00
github-actions[bot]	19a461a19e	📝 Update release notes [skip ci]	2026-07-28 13:31:47 +00:00
Sebastián Ramírez	0a4cd1c78f	🐛 Preserve pytest exit code in regression check (#16091 )	2026-07-28 15:31:02 +02:00
github-actions[bot]	64ae6c977c	📝 Update release notes [skip ci]	2026-07-28 13:16:59 +00:00
Sebastián Ramírez	7d123d9537	✅ Test PR regressions against base code (#16090 )	2026-07-28 13:16:17 +00:00
Sebastián Ramírezandgithub-actions[bot]	6b6c032658	🔖 Release version 0.140.9 (#16089 ) Co-authored-by: github-actions[bot] <github-actions[bot]@users.noreply.github.com>	2026-07-28 12:36:53 +00:00
github-actions[bot]	506eba8ac3	📝 Update release notes [skip ci]	2026-07-28 12:28:57 +00:00
Muhammad Bin GulzarandSebastián Ramírez	aadfcce763	🐛 Fix `exclude_defaults` not propagated to dict keys and values in `jsonable_encoder` (#16043 ) Co-authored-by: Sebastián Ramírez <tiangolo@gmail.com>	2026-07-28 12:28:18 +00:00
github-actions[bot]	4ffd451720	📝 Update release notes [skip ci]	2026-07-28 12:21:55 +00:00
dependabot[bot]	5e8b7f1cb5	⬆ Bump gitpython from 3.1.50 to 3.1.54 (#16047 ) Signed-off-by: dependabot[bot] <support@github.com> Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>	2026-07-28 14:18:40 +02:00
github-actions[bot]	c4e91df63b	📝 Update release notes [skip ci]	2026-07-28 12:17:20 +00:00
dependabot[bot]	53363a6be1	⬆ Bump pymdown-extensions from 10.21.3 to 11.0 (#16048 ) Signed-off-by: dependabot[bot] <support@github.com> Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>	2026-07-28 14:16:46 +02:00
github-actions[bot]	8b041fe96a	📝 Update release notes [skip ci]	2026-07-28 12:10:23 +00:00
dependabot[bot]	ba86fc13b4	⬆ Bump pyasn1 from 0.6.3 to 0.6.4 (#16045 ) Signed-off-by: dependabot[bot] <support@github.com> Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>	2026-07-28 14:09:41 +02:00
Sebastián Ramírezandgithub-actions[bot]	773342f978	🔖 Release version 0.140.8 (#16088 ) Co-authored-by: github-actions[bot] <github-actions[bot]@users.noreply.github.com>	2026-07-28 10:29:51 +00:00
github-actions[bot]	fd557905ea	📝 Update release notes [skip ci]	2026-07-28 10:22:53 +00:00
Alexander Rauhut Alexander Rauhut Sebastián Ramírez	ad03e117c0	🐛 Fix stream item type lost when using `include_router()` (#15077 ) Co-authored-by: Alexander Rauhut <alexander.rauhut@adnova.gmbh> Co-authored-by: Sebastián Ramírez <tiangolo@gmail.com>	2026-07-28 12:22:08 +02:00
Sebastián Ramírezandgithub-actions[bot]	98b12fe56f	🔖 Release version 0.140.7 (#16078 ) Co-authored-by: github-actions[bot] <github-actions[bot]@users.noreply.github.com>	2026-07-27 17:28:03 +00:00
github-actions[bot]	e772894447	📝 Update release notes [skip ci]	2026-07-27 17:26:20 +00:00
Sebastián Ramírez	24c2a9fdf9	⬆️ Upgrade latest-changes to 0.7.1 (#16077 )	2026-07-27 19:25:00 +02:00
github-actions[bot]	add1d2685b	📝 Update release notes [skip ci]	2026-07-27 17:17:14 +00:00
Sebastián Ramírez	7bcb78d10d	⚡️ Avoid flattening dependencies for OpenAPI (#16076 )	2026-07-27 17:16:40 +00:00
github-actions[bot]	87095aa581	📝 Update release notes [skip ci]	2026-07-27 16:47:36 +00:00
Sebastián Ramírez	3d3c6913e8	👷 Add OpenAPI dependency benchmarks (#16075 )	2026-07-27 18:46:54 +02:00
Sebastián Ramírezandgithub-actions[bot]	bcd4e895e1	🔖 Release version 0.140.6 (#16074 ) Co-authored-by: github-actions[bot] <github-actions[bot]@users.noreply.github.com>	2026-07-27 16:28:46 +00:00
github-actions[bot]	27c922c403	📝 Update release notes [skip ci]	2026-07-27 16:18:08 +00:00
Sebastián Ramírez	cc96fd3a7c	⚡️ Avoid flattening dependencies for request parameters, mainly for OpenAPI (#16073 )	2026-07-27 16:17:33 +00:00
Sebastián Ramírezandgithub-actions[bot]	ac068db630	🔖 Release version 0.140.5 (#16072 ) Co-authored-by: github-actions[bot] <github-actions[bot]@users.noreply.github.com>	2026-07-27 16:00:25 +00:00
github-actions[bot]	6be87d13a7	📝 Update release notes [skip ci]	2026-07-27 15:53:30 +00:00
Sebastián Ramírez	23e4a10434	⚡️ Avoid flattening dependencies for body fields (#16071 )	2026-07-27 15:52:55 +00:00
Sebastián Ramírezandgithub-actions[bot]	7ac0f1b541	🔖 Release version 0.140.4 (#16070 ) Co-authored-by: github-actions[bot] <github-actions[bot]@users.noreply.github.com>	2026-07-27 15:45:50 +00:00
github-actions[bot]	44e4eeaa78	📝 Update release notes [skip ci]	2026-07-27 15:36:07 +00:00
Sebastián Ramírez	7134121a71	⚡️ Skip unused dependency repeat bookkeeping (#16069 )	2026-07-27 15:35:29 +00:00
Sebastián Ramírezandgithub-actions[bot]	415d37fa6f	🔖 Release version 0.140.3 (#16068 ) Co-authored-by: github-actions[bot] <github-actions[bot]@users.noreply.github.com>	2026-07-27 15:16:54 +00:00
github-actions[bot]	ca353d7215	📝 Update release notes [skip ci]	2026-07-27 15:09:32 +00:00
Sebastián Ramírez	d012979f9a	⚡️ Avoid repeated dependency flattening in OpenAPI (#16067 )	2026-07-27 15:08:45 +00:00
Sebastián Ramírezandgithub-actions[bot]	051dfeddcc	🔖 Release version 0.140.2 (#16066 ) Co-authored-by: github-actions[bot] <github-actions[bot]@users.noreply.github.com>	2026-07-27 14:14:11 +00:00
github-actions[bot]	e9980492f2	📝 Update release notes [skip ci]	2026-07-27 14:07:09 +00:00
Sebastián RamírezandMarcelo Trylesinski	8069eadf5e	⚡️ Stop retaining flat dependency trees (#16065 ) Co-authored-by: Marcelo Trylesinski <marcelotryle@gmail.com>	2026-07-27 16:06:31 +02:00
github-actions[bot]	2b4349d6c2	📝 Update release notes [skip ci]	2026-07-27 12:40:07 +00:00
Sebastián Ramírez	2f34b90742	👷 Add new memory benchmark (#16064 )	2026-07-27 12:39:36 +00:00
Sebastián Ramírezandgithub-actions[bot]	3e310c90fa	🔖 Release version 0.140.1 (#16063 ) Co-authored-by: github-actions[bot] <github-actions[bot]@users.noreply.github.com>	2026-07-27 14:06:27 +02:00
github-actions[bot]	43eafc6a28	📝 Update release notes [skip ci]	2026-07-27 11:18:58 +00:00
Sebastián Ramírez	65ef53ae6a	♻️ Update the lru_cache limit for dependencies to account for large apps (#16062 )	2026-07-27 11:18:26 +00:00