Implement GET /api/v1/announcements/:id

lib/pleroma/web/mastodon_api/controllers/announcement_controller.ex

@@ -55,7 +55,20 @@ def mark_read(_conn, _params) do
   end
 
   @doc "POST /api/v1/announcements/:id"
-  def show(_conn, _params) do
+  def show(%{assigns: %{user: user}} = conn, %{id: id} = _params) do
-    {:error, :not_found}
+    render_announcement_by_id(conn, id, user)
+  end
+
+  def show(conn, %{id: id} = _params) do
+    render_announcement_by_id(conn, id)
+  end
+
+  def render_announcement_by_id(conn, id, user \\ nil) do
+    with announcement when not is_nil(announcement) <- Announcement.get_by_id(id) do
+      render(conn, "show.json", announcement: announcement, user: user)
+    else
+      _ ->
+        {:error, :not_found}
+    end
   end
 end

test/pleroma/web/mastodon_api/controllers/announcement_controller_test.exs

@@ -51,4 +51,56 @@ test "when authenticated and announcement is read by user" do
       assert [%{"id" => ^id, "read" => true}] = response
     end
   end
+
+  describe "GET /api/v1/announcements/:id" do
+    test "it shows one announcement" do
+      %{id: id} = insert(:announcement)
+
+      response =
+        build_conn()
+        |> get("/api/v1/announcements/#{id}")
+        |> json_response_and_validate_schema(:ok)
+
+      assert %{"id" => ^id} = response
+      refute Map.has_key?(response, "read")
+    end
+
+    test "it gives 404 for non-existent announcements" do
+      %{id: id} = insert(:announcement)
+
+      _response =
+        build_conn()
+        |> get("/api/v1/announcements/#{id}xxx")
+        |> json_response_and_validate_schema(:not_found)
+    end
+
+    test "when authenticated, also expose read property" do
+      %{id: id} = insert(:announcement)
+
+      %{conn: conn} = oauth_access(["read:accounts"])
+
+      response =
+        conn
+        |> get("/api/v1/announcements/#{id}")
+        |> json_response_and_validate_schema(:ok)
+
+      assert %{"id" => ^id, "read" => false} = response
+    end
+
+    test "when authenticated and announcement is read by user" do
+      %{id: id} = announcement = insert(:announcement)
+      user = insert(:user)
+
+      AnnouncementReadRelationship.mark_read(user, announcement)
+
+      %{conn: conn} = oauth_access(["read:accounts"], user: user)
+
+      response =
+        conn
+        |> get("/api/v1/announcements/#{id}")
+        |> json_response_and_validate_schema(:ok)
+
+      assert %{"id" => ^id, "read" => true} = response
+    end
+  end
 end