import base64 from collections.abc import AsyncIterable, Iterable from io import BytesIO from fastapi import FastAPI from fastapi.responses import StreamingResponse image_base64 = "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" binary_image = base64.b64decode(image_base64) def read_image() -> BytesIO: return BytesIO(binary_image) app = FastAPI() class PNGStreamingResponse(StreamingResponse): media_type = "image/png" @app.get("/image/stream", response_class=PNGStreamingResponse) async def stream_image() -> AsyncIterable[bytes]: with read_image() as image_file: for chunk in image_file: yield chunk @app.get("/image/stream-no-async", response_class=PNGStreamingResponse) def stream_image_no_async() -> Iterable[bytes]: with read_image() as image_file: for chunk in image_file: yield chunk @app.get("/image/stream-no-async-yield-from", response_class=PNGStreamingResponse) def stream_image_no_async_yield_from() -> Iterable[bytes]: with read_image() as image_file: yield from image_file @app.get("/image/stream-no-annotation", response_class=PNGStreamingResponse) async def stream_image_no_annotation(): with read_image() as image_file: for chunk in image_file: yield chunk @app.get("/image/stream-no-async-no-annotation", response_class=PNGStreamingResponse) def stream_image_no_async_no_annotation(): with read_image() as image_file: for chunk in image_file: yield chunk