graph: support $expand=children on drive special folders

services/graph/pkg/service/v0/driveitems_special.go

@@ -24,6 +24,7 @@ const RecycleBinSpecialFolderName = "recyclebin"
 
 // GetDriveSpecial returns the driveItem of a special folder. In the colon path
 // form (special/recyclebin:/{key}) it returns the trashed item with that key.
+// $expand=children embeds the listing for folders.
 func (g Graph) GetDriveSpecial(w http.ResponseWriter, r *http.Request) {
 	g.logger.Debug().Msg("Calling GetDriveSpecial")
 
@@ -33,29 +34,45 @@ func (g Graph) GetDriveSpecial(w http.ResponseWriter, r *http.Request) {
 	}
 
 	key := specialFolderKey(r)
-	if key == "" {
-		render.Status(r, http.StatusOK)
-		render.JSON(w, r, recycleBinDriveItem(&driveID))
+	driveItem, ok := g.getSpecialDriveItemForKey(w, r, &driveID, key)
+	if !ok {
 		return
 	}
 
+	if driveItem.Folder != nil && driveItemRelationExpanded(r, _expandChildren) {
+		children, ok := g.listRecycleChildren(w, r, &driveID, key)
+		if !ok {
+			return
+		}
+		driveItem.Children = children
+	}
+
+	render.Status(r, http.StatusOK)
+	render.JSON(w, r, driveItem)
+}
+
+// getSpecialDriveItemForKey returns the trash root for an empty key, else the trashed item with that key
+func (g Graph) getSpecialDriveItemForKey(w http.ResponseWriter, r *http.Request, driveID *storageprovider.ResourceId, key string) (*libregraph.DriveItem, bool) {
+	if key == "" {
+		return recycleBinDriveItem(driveID), true
+	}
+
 	// A top-level key lists itself, a nested key only shows up in its parent's listing.
 	listKey := key
 	if strings.Contains(key, "/") {
 		listKey = path.Dir(key) + "/"
 	}
-	items, ok := g.listRecycle(w, r, &driveID, listKey)
+	items, ok := g.listRecycle(w, r, driveID, listKey)
 	if !ok {
-		return
+		return nil, false
 	}
 	for _, item := range items {
 		if item.GetKey() == key {
-			render.Status(r, http.StatusOK)
-			render.JSON(w, r, recycleItemToDriveItem(&driveID, item))
-			return
+			return recycleItemToDriveItem(driveID, item), true
 		}
 	}
 	errorcode.ItemNotFound.Render(w, r, http.StatusNotFound, "item not found")
+	return nil, false
 }
 
 // ListDriveSpecialChildren lists the children of a special folder. For the
@@ -69,25 +86,34 @@ func (g Graph) ListDriveSpecialChildren(w http.ResponseWriter, r *http.Request)
 		return
 	}
 
-	// the trailing slash asks reva for the children of the key instead of the key itself
-	listKey := ""
-	if key := specialFolderKey(r); key != "" {
-		listKey = key + "/"
-	}
-	items, ok := g.listRecycle(w, r, &driveID, listKey)
+	files, ok := g.listRecycleChildren(w, r, &driveID, specialFolderKey(r))
 	if !ok {
 		return
 	}
 
-	files := make([]libregraph.DriveItem, 0, len(items))
-	for _, item := range items {
-		files = append(files, *recycleItemToDriveItem(&driveID, item))
-	}
-
 	render.Status(r, http.StatusOK)
 	render.JSON(w, r, &ListResponse{Value: files})
 }
 
+// listRecycleChildren lists the trash root for an empty key, else the children of the trashed folder with that key
+func (g Graph) listRecycleChildren(w http.ResponseWriter, r *http.Request, driveID *storageprovider.ResourceId, key string) ([]libregraph.DriveItem, bool) {
+	// the trailing slash asks reva for the children of the key instead of the key itself
+	listKey := ""
+	if key != "" {
+		listKey = key + "/"
+	}
+	items, ok := g.listRecycle(w, r, driveID, listKey)
+	if !ok {
+		return nil, false
+	}
+
+	files := make([]libregraph.DriveItem, 0, len(items))
+	for _, item := range items {
+		files = append(files, *recycleItemToDriveItem(driveID, item))
+	}
+	return files, true
+}
+
 func parseSpecialParams(w http.ResponseWriter, r *http.Request) (storageprovider.ResourceId, bool) {
 	driveID, err := parseIDParam(r, "driveID")
 	if err != nil {

services/graph/pkg/service/v0/driveitems_special_test.go

@@ -57,10 +57,10 @@ var _ = Describe("Drive special folders", func() {
 		deletedAt = time.Date(2026, 9, 7, 12, 0, 0, 0, time.UTC)
 	)
 
-	// newRequest builds a request for /drives/{driveID}/special/{specialName}[/children];
+	// newRequestWithQuery builds a request for /drives/{driveID}/special/{specialName}[/children];
 	// specialPath mimics what the colon-path middleware puts into the context.
-	newRequest := func(specialName, specialPath string) *http.Request {
-		r := httptest.NewRequest(http.MethodGet, "/graph/v1.0/drives/storageid$spaceid/special/"+specialName, nil)
+	newRequestWithQuery := func(specialName, specialPath, query string) *http.Request {
+		r := httptest.NewRequest(http.MethodGet, "/graph/v1.0/drives/storageid$spaceid/special/"+specialName+query, nil)
 		rctx := chi.NewRouteContext()
 		rctx.URLParams.Add("driveID", "storageid$spaceid")
 		rctx.URLParams.Add("specialName", specialName)
@@ -70,6 +70,9 @@ var _ = Describe("Drive special folders", func() {
 		}
 		return r.WithContext(c)
 	}
+	newRequest := func(specialName, specialPath string) *http.Request {
+		return newRequestWithQuery(specialName, specialPath, "")
+	}
 
 	decodeItem := func() libregraph.DriveItem {
 		var item libregraph.DriveItem
@@ -200,6 +203,71 @@ var _ = Describe("Drive special folders", func() {
 			Expect(item.File).To(BeNil())
 		})
 
+		It("embeds the trash listing with $expand=children", func() {
+			var keys []string
+			gatewayClient.On("ListRecycle", mock.Anything, mock.Anything).Run(func(args mock.Arguments) {
+				keys = append(keys, args.Get(1).(*provider.ListRecycleRequest).GetKey())
+			}).Return(&provider.ListRecycleResponse{
+				Status: status.NewOK(ctx),
+				RecycleItems: []*provider.RecycleItem{
+					{Type: provider.ResourceType_RESOURCE_TYPE_FILE, Key: "nodeid", Ref: &provider.Reference{Path: "/a.txt"}},
+				},
+			}, nil)
+
+			svc.GetDriveSpecial(rr, newRequestWithQuery("recyclebin", "", "?$expand=children"))
+			Expect(rr.Code).To(Equal(http.StatusOK))
+			Expect(keys).To(Equal([]string{""}))
+
+			item := decodeItem()
+			Expect(item.GetId()).To(Equal("storageid$spaceid!recyclebin"))
+			Expect(item.Children).To(HaveLen(1))
+			Expect(item.Children[0].GetId()).To(Equal("storageid$spaceid!nodeid"))
+			Expect(item.Children[0].Trash).ToNot(BeNil())
+		})
+
+		It("embeds the children of a trashed folder with $expand=children", func() {
+			var keys []string
+			gatewayClient.On("ListRecycle", mock.Anything, mock.Anything).Run(func(args mock.Arguments) {
+				keys = append(keys, args.Get(1).(*provider.ListRecycleRequest).GetKey())
+			}).Return(&provider.ListRecycleResponse{
+				Status: status.NewOK(ctx),
+				RecycleItems: []*provider.RecycleItem{
+					{Type: provider.ResourceType_RESOURCE_TYPE_CONTAINER, Key: "nodeid", Ref: &provider.Reference{Path: "/folder"}},
+				},
+			}, nil).Once()
+			gatewayClient.On("ListRecycle", mock.Anything, mock.Anything).Run(func(args mock.Arguments) {
+				keys = append(keys, args.Get(1).(*provider.ListRecycleRequest).GetKey())
+			}).Return(&provider.ListRecycleResponse{
+				Status: status.NewOK(ctx),
+				RecycleItems: []*provider.RecycleItem{
+					{Type: provider.ResourceType_RESOURCE_TYPE_FILE, Key: "nodeid/a.txt", Ref: &provider.Reference{Path: "/folder/a.txt"}},
+				},
+			}, nil).Once()
+
+			svc.GetDriveSpecial(rr, newRequestWithQuery("recyclebin", "/nodeid", "?$expand=children"))
+			Expect(rr.Code).To(Equal(http.StatusOK))
+			Expect(keys).To(Equal([]string{"nodeid", "nodeid/"}))
+
+			item := decodeItem()
+			Expect(item.GetId()).To(Equal("storageid$spaceid!nodeid"))
+			Expect(item.Children).To(HaveLen(1))
+			Expect(item.Children[0].GetId()).To(Equal("storageid$spaceid!nodeid/a.txt"))
+		})
+
+		It("does not expand children of a trashed file", func() {
+			gatewayClient.On("ListRecycle", mock.Anything, mock.Anything).Return(&provider.ListRecycleResponse{
+				Status: status.NewOK(ctx),
+				RecycleItems: []*provider.RecycleItem{
+					{Type: provider.ResourceType_RESOURCE_TYPE_FILE, Key: "nodeid", Ref: &provider.Reference{Path: "/a.txt"}},
+				},
+			}, nil)
+
+			svc.GetDriveSpecial(rr, newRequestWithQuery("recyclebin", "/nodeid", "?$expand=children"))
+			Expect(rr.Code).To(Equal(http.StatusOK))
+			gatewayClient.AssertNumberOfCalls(GinkgoT(), "ListRecycle", 1)
+			Expect(decodeItem().Children).To(BeNil())
+		})
+
 		It("returns not found when the key is not in the listing", func() {
 			gatewayClient.On("ListRecycle", mock.Anything, mock.Anything).Return(&provider.ListRecycleResponse{
 				Status:       status.NewOK(ctx),