fix(channels): keep the backend task channel in sync on rename and delete

packages/api-client/src/posthog-client.ts

@@ -2286,6 +2286,50 @@ export class PostHogAPIClient {
     return (await response.json()) as TaskChannel[];
   }
 
+  // Rename a public channel by id, so its task feed follows the new name.
+  async renameTaskChannel(id: string, name: string): Promise<TaskChannel> {
+    const teamId = await this.getTeamId();
+    const urlPath = `/api/projects/${teamId}/task_channels/${encodeURIComponent(id)}/`;
+    const response = await this.api.fetcher.fetch({
+      method: "patch",
+      url: new URL(`${this.api.baseUrl}${urlPath}`),
+      path: urlPath,
+      overrides: { body: JSON.stringify({ name }) },
+    });
+    if (!response.ok) {
+      // The backend rejects invalid/taken names with a JSON `detail` message.
+      const detail = await response
+        .json()
+        .then((body) => (body as { detail?: string }).detail)
+        .catch(() => undefined);
+      throw new Error(
+        `Failed to rename task channel: ${detail ?? response.statusText}`,
+      );
+    }
+    return (await response.json()) as TaskChannel;
+  }
+
+  // Delete a public channel by id. Soft-delete server-side, so the channel's
+  // tasks and messages are recoverable.
+  async deleteTaskChannel(id: string): Promise<void> {
+    const teamId = await this.getTeamId();
+    const urlPath = `/api/projects/${teamId}/task_channels/${encodeURIComponent(id)}/`;
+    const response = await this.api.fetcher.fetch({
+      method: "delete",
+      url: new URL(`${this.api.baseUrl}${urlPath}`),
+      path: urlPath,
+    });
+    if (!response.ok) {
+      const detail = await response
+        .json()
+        .then((body) => (body as { detail?: string }).detail)
+        .catch(() => undefined);
+      throw new Error(
+        `Failed to delete task channel: ${detail ?? response.statusText}`,
+      );
+    }
+  }
+
   // Resolve-or-create a public channel by name (idempotent server-side).
   async resolveTaskChannel(name: string): Promise<TaskChannel> {
     const teamId = await this.getTeamId();

packages/ui/src/features/canvas/components/ChannelsList.tsx

@@ -117,7 +117,7 @@ function useChannelActions(channel: Channel): {
         ),
       ]);
 
-      await deleteChannel(channel.id);
+      await deleteChannel(channel.id, channel.name);
       removeStar();
       track(ANALYTICS_EVENTS.CHANNEL_ACTION, {
         action_type: "delete",
@@ -444,8 +444,8 @@ function ChannelSection({ channel }: { channel: Channel }) {
                   Every canvas saved in this channel is permanently deleted.
                 </li>
                 <li>
-                  Filed tasks are removed from the channel, but the tasks
-                  themselves are not deleted.
+                  Tasks in this channel are deleted with it. Their data is
+                  retained, so they can be restored later.
                 </li>
               </ul>
             </AlertDialogDescription>

packages/ui/src/features/canvas/components/RenameChannelModal.tsx

@@ -39,7 +39,7 @@ export function RenameChannelModal({
   const submit = async () => {
     if (!trimmed || unchanged || validationError || isRenaming) return;
     try {
-      await renameChannel(channel.id, trimmed);
+      await renameChannel(channel.id, trimmed, channel.name);
       track(ANALYTICS_EVENTS.CHANNEL_ACTION, {
         action_type: "rename",
         surface: "sidebar",

packages/ui/src/features/canvas/hooks/useChannels.test.tsx

@@ -1,4 +1,5 @@
 import type { Schemas } from "@posthog/api-client";
+import type { TaskChannel } from "@posthog/shared/domain-types";
 import { QueryClient, QueryClientProvider } from "@tanstack/react-query";
 import { act, renderHook, waitFor } from "@testing-library/react";
 import type { ReactNode } from "react";
@@ -7,6 +8,13 @@ import { beforeEach, describe, expect, it, vi } from "vitest";
 const mockClient = vi.hoisted(() => ({
   getDesktopFileSystemChannels: vi.fn(),
   createDesktopFileSystemChannel: vi.fn(),
+  renameDesktopFileSystemChannel: vi.fn(),
+  deleteDesktopFileSystem: vi.fn(),
+  getTaskChannels: vi.fn(),
+  renameTaskChannel: vi.fn(),
+  deleteTaskChannel: vi.fn(),
+  getTasks: vi.fn(),
+  deleteTask: vi.fn(),
 }));
 vi.mock("@posthog/ui/features/auth/authClient", () => ({
   useOptionalAuthenticatedClient: () => mockClient,
@@ -99,3 +107,205 @@ describe("useChannelMutations", () => {
     expect(list.result.current.channels.map((c) => c.id)).toEqual(["1"]);
   });
 });
+
+describe("useChannelMutations rename", () => {
+  function taskChannel(
+    id: string,
+    name: string,
+    channel_type: TaskChannel["channel_type"] = "public",
+  ): TaskChannel {
+    return { id, name, channel_type, created_at: "2026-01-01T00:00:00Z" };
+  }
+
+  beforeEach(() => {
+    vi.clearAllMocks();
+    queryClient = new QueryClient({
+      defaultOptions: { queries: { retry: false } },
+    });
+  });
+
+  it("renames the backend task channel alongside the folder", async () => {
+    // The feed's backend channel is looked up by name, so a folder rename
+    // must carry it along or the channel's tasks/messages are orphaned.
+    mockClient.getTaskChannels.mockResolvedValue([
+      taskChannel("bc-1", "mobile"),
+      taskChannel("bc-2", "web"),
+    ]);
+    mockClient.renameTaskChannel.mockResolvedValue(
+      taskChannel("bc-1", "mobile-app"),
+    );
+    mockClient.renameDesktopFileSystemChannel.mockResolvedValue(
+      folder("1", "mobile-app"),
+    );
+
+    const mutations = renderHook(() => useChannelMutations(), { wrapper });
+    await act(async () => {
+      await mutations.result.current.renameChannel("1", "mobile-app", "mobile");
+    });
+
+    expect(mockClient.renameTaskChannel).toHaveBeenCalledWith(
+      "bc-1",
+      "mobile-app",
+    );
+    expect(mockClient.renameDesktopFileSystemChannel).toHaveBeenCalledWith(
+      "1",
+      "mobile-app",
+    );
+  });
+
+  it("skips the backend rename when no backend channel has the old name", async () => {
+    mockClient.getTaskChannels.mockResolvedValue([taskChannel("bc-2", "web")]);
+    mockClient.renameDesktopFileSystemChannel.mockResolvedValue(
+      folder("1", "mobile-app"),
+    );
+
+    const mutations = renderHook(() => useChannelMutations(), { wrapper });
+    await act(async () => {
+      await mutations.result.current.renameChannel("1", "mobile-app", "mobile");
+    });
+
+    expect(mockClient.renameTaskChannel).not.toHaveBeenCalled();
+    expect(mockClient.renameDesktopFileSystemChannel).toHaveBeenCalledWith(
+      "1",
+      "mobile-app",
+    );
+  });
+
+  it("does not rename the folder when the backend rename fails", async () => {
+    mockClient.getTaskChannels.mockResolvedValue([
+      taskChannel("bc-1", "mobile"),
+    ]);
+    mockClient.renameTaskChannel.mockRejectedValue(new Error("name taken"));
+
+    const mutations = renderHook(() => useChannelMutations(), { wrapper });
+    await expect(
+      act(() =>
+        mutations.result.current.renameChannel("1", "mobile-app", "mobile"),
+      ),
+    ).rejects.toThrow("name taken");
+
+    expect(mockClient.renameDesktopFileSystemChannel).not.toHaveBeenCalled();
+  });
+
+  it("reverts the backend rename when the folder rename fails", async () => {
+    mockClient.getTaskChannels.mockResolvedValue([
+      taskChannel("bc-1", "mobile"),
+    ]);
+    mockClient.renameTaskChannel.mockResolvedValue(
+      taskChannel("bc-1", "mobile-app"),
+    );
+    mockClient.renameDesktopFileSystemChannel.mockRejectedValue(
+      new Error("folder rename failed"),
+    );
+
+    const mutations = renderHook(() => useChannelMutations(), { wrapper });
+    await expect(
+      act(() =>
+        mutations.result.current.renameChannel("1", "mobile-app", "mobile"),
+      ),
+    ).rejects.toThrow("folder rename failed");
+
+    expect(mockClient.renameTaskChannel).toHaveBeenNthCalledWith(
+      1,
+      "bc-1",
+      "mobile-app",
+    );
+    expect(mockClient.renameTaskChannel).toHaveBeenNthCalledWith(
+      2,
+      "bc-1",
+      "mobile",
+    );
+  });
+});
+
+describe("useChannelMutations delete", () => {
+  function taskChannel(
+    id: string,
+    name: string,
+    channel_type: TaskChannel["channel_type"] = "public",
+  ): TaskChannel {
+    return { id, name, channel_type, created_at: "2026-01-01T00:00:00Z" };
+  }
+
+  beforeEach(() => {
+    vi.clearAllMocks();
+    queryClient = new QueryClient({
+      defaultOptions: { queries: { retry: false } },
+    });
+  });
+
+  it("soft-deletes the backend channel's tasks and the channel before the folder", async () => {
+    mockClient.getTaskChannels.mockResolvedValue([
+      taskChannel("bc-1", "mobile"),
+      taskChannel("bc-2", "web"),
+    ]);
+    mockClient.getTasks.mockResolvedValue([{ id: "t-1" }, { id: "t-2" }]);
+    mockClient.deleteTask.mockResolvedValue(undefined);
+    mockClient.deleteTaskChannel.mockResolvedValue(undefined);
+    mockClient.deleteDesktopFileSystem.mockResolvedValue(undefined);
+
+    const mutations = renderHook(() => useChannelMutations(), { wrapper });
+    await act(async () => {
+      await mutations.result.current.deleteChannel("1", "mobile");
+    });
+
+    expect(mockClient.getTasks).toHaveBeenCalledWith({ channel: "bc-1" });
+    expect(mockClient.deleteTask).toHaveBeenCalledWith("t-1");
+    expect(mockClient.deleteTask).toHaveBeenCalledWith("t-2");
+    expect(mockClient.deleteTaskChannel).toHaveBeenCalledWith("bc-1");
+    expect(mockClient.deleteDesktopFileSystem).toHaveBeenCalledWith("1");
+  });
+
+  it("deletes just the folder when no backend channel matches the name", async () => {
+    mockClient.getTaskChannels.mockResolvedValue([taskChannel("bc-2", "web")]);
+    mockClient.deleteDesktopFileSystem.mockResolvedValue(undefined);
+
+    const mutations = renderHook(() => useChannelMutations(), { wrapper });
+    await act(async () => {
+      await mutations.result.current.deleteChannel("1", "mobile");
+    });
+
+    expect(mockClient.getTasks).not.toHaveBeenCalled();
+    expect(mockClient.deleteTaskChannel).not.toHaveBeenCalled();
+    expect(mockClient.deleteDesktopFileSystem).toHaveBeenCalledWith("1");
+  });
+
+  it("still deletes the backend channel when a task soft delete fails", async () => {
+    // Task deletes are best-effort: a straggler stays attached to the
+    // soft-deleted channel (recoverable) rather than blocking the delete.
+    mockClient.getTaskChannels.mockResolvedValue([
+      taskChannel("bc-1", "mobile"),
+    ]);
+    mockClient.getTasks.mockResolvedValue([{ id: "t-1" }, { id: "t-2" }]);
+    mockClient.deleteTask
+      .mockRejectedValueOnce(new Error("task delete failed"))
+      .mockResolvedValueOnce(undefined);
+    mockClient.deleteTaskChannel.mockResolvedValue(undefined);
+    mockClient.deleteDesktopFileSystem.mockResolvedValue(undefined);
+
+    const mutations = renderHook(() => useChannelMutations(), { wrapper });
+    await act(async () => {
+      await mutations.result.current.deleteChannel("1", "mobile");
+    });
+
+    expect(mockClient.deleteTaskChannel).toHaveBeenCalledWith("bc-1");
+    expect(mockClient.deleteDesktopFileSystem).toHaveBeenCalledWith("1");
+  });
+
+  it("does not delete the folder when the backend channel delete fails", async () => {
+    mockClient.getTaskChannels.mockResolvedValue([
+      taskChannel("bc-1", "mobile"),
+    ]);
+    mockClient.getTasks.mockResolvedValue([]);
+    mockClient.deleteTaskChannel.mockRejectedValue(
+      new Error("channel delete failed"),
+    );
+
+    const mutations = renderHook(() => useChannelMutations(), { wrapper });
+    await expect(
+      act(() => mutations.result.current.deleteChannel("1", "mobile")),
+    ).rejects.toThrow("channel delete failed");
+
+    expect(mockClient.deleteDesktopFileSystem).not.toHaveBeenCalled();
+  });
+});