Add the ability to delete a message (#53)

Message.deleted_at has existed since the initial schema but was never wired up -- no WS envelope, no permission check, no frontend concept of it at all. Soft delete, author-only (mirrors the existing edit permission exactly): content and any attached image/file are cleared and the underlying MessageImage/MessageFile row and stored file are actually removed, not just detached, so the message becomes a "This message was deleted" tombstone with nothing left to recover through a stale attachment URL. A deleted message can no longer be edited or reacted to. Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
2026-08-28 16:35:00 -06:00
parent 157f1e30ac
commit ef615e1ef4
13 changed files with 477 additions and 8 deletions
@@ -0,0 +1,222 @@
+import io
+import uuid
+
+from PIL import Image
+
+from app.schemas.user import UserCreate
+from app.services.auth_service import register_user
+
+
+def _unique(prefix: str) -> str:
+    return f"{prefix}-{uuid.uuid4().hex[:8]}"
+
+
+_NOISE_TYPES = {"member_updated", "desktop_notification", "unread_update"}
+
+
+def _recv(ws) -> dict:
+    """Reads the next frame, transparently discarding presence/offline-
+    notify noise -- see test_message_edit.py's identical helper."""
+    while True:
+        msg = ws.receive_json()
+        if msg.get("type") not in _NOISE_TYPES:
+            return msg
+
+
+def _register_ws(ws_client, username: str) -> dict:
+    async def _seed():
+        async with ws_client.session_factory() as session:
+            await register_user(
+                session,
+                UserCreate(username=username, email=f"{username}@example.com", password="password123"),
+            )
+
+    ws_client.portal.call(_seed)
+    resp = ws_client.post(
+        "/api/auth/login", json={"username_or_email": username, "password": "password123"}
+    )
+    assert resp.status_code == 200, resp.text
+    return resp.json()
+
+
+def _png_bytes() -> bytes:
+    buf = io.BytesIO()
+    Image.new("RGB", (10, 10), color=(255, 0, 0)).save(buf, format="PNG")
+    return buf.getvalue()
+
+
+def test_ws_delete_clears_content_and_broadcasts(ws_client):
+    username = _unique("alice")
+    _register_ws(ws_client, username=username)
+    room = ws_client.post("/api/rooms", json={"name": _unique("general")}).json()
+
+    with ws_client.websocket_connect("/ws/chat") as ws:
+        ws.send_json({"type": "join", "room_id": room["id"]})
+        assert ws.receive_json()["type"] == "joined"
+
+        ws.send_json({"type": "message", "room_id": room["id"], "content": "hello"})
+        message = ws.receive_json()
+
+        ws.send_json({"type": "delete", "room_id": room["id"], "message_id": message["id"]})
+        deleted = ws.receive_json()
+        assert deleted == {"type": "message_deleted", "id": message["id"], "room_id": room["id"]}
+
+    resp = ws_client.get(f"/api/rooms/{room['id']}/messages")
+    history = resp.json()
+    tombstone = next(m for m in history if m["id"] == message["id"])
+    assert tombstone["content"] is None
+    assert tombstone["deleted_at"] is not None
+    assert tombstone["image_id"] is None
+    assert tombstone["file"] is None
+
+
+def test_ws_delete_rejects_non_author(ws_client):
+    alice = _register_ws(ws_client, username=_unique("alice"))
+    room = ws_client.post("/api/rooms", json={"name": _unique("general")}).json()
+
+    bob = _register_ws(ws_client, username=_unique("bob"))
+    ws_client.post(f"/api/rooms/{room['id']}/join")
+
+    ws_client.post(
+        "/api/auth/login", json={"username_or_email": alice["username"], "password": "password123"}
+    )
+    with ws_client.websocket_connect("/ws/chat") as alice_ws:
+        alice_ws.send_json({"type": "join", "room_id": room["id"]})
+        assert alice_ws.receive_json()["type"] == "joined"
+        alice_ws.send_json({"type": "message", "room_id": room["id"], "content": "hello"})
+        message = alice_ws.receive_json()
+
+        ws_client.post(
+            "/api/auth/login",
+            json={"username_or_email": bob["username"], "password": "password123"},
+        )
+        with ws_client.websocket_connect("/ws/chat") as bob_ws:
+            bob_ws.send_json({"type": "join", "room_id": room["id"]})
+            assert _recv(bob_ws)["type"] == "joined"
+            bob_ws.send_json(
+                {"type": "delete", "room_id": room["id"], "message_id": message["id"]}
+            )
+            resp = bob_ws.receive_json()
+            assert resp["type"] == "error"
+            assert "own messages" in resp["detail"]
+
+    resp = ws_client.get(f"/api/rooms/{room['id']}/messages")
+    history = resp.json()
+    still_there = next(m for m in history if m["id"] == message["id"])
+    assert still_there["deleted_at"] is None
+    assert still_there["content"] == "hello"
+
+
+def test_ws_delete_of_unknown_message_errors(ws_client):
+    _register_ws(ws_client, username=_unique("alice"))
+    room = ws_client.post("/api/rooms", json={"name": _unique("general")}).json()
+
+    with ws_client.websocket_connect("/ws/chat") as ws:
+        ws.send_json({"type": "join", "room_id": room["id"]})
+        assert ws.receive_json()["type"] == "joined"
+
+        ws.send_json(
+            {"type": "delete", "room_id": room["id"], "message_id": str(uuid.uuid4())}
+        )
+        resp = ws.receive_json()
+        assert resp == {"type": "error", "detail": "Message not found"}
+
+
+def test_deleted_message_cannot_be_edited_or_reacted_to(ws_client):
+    _register_ws(ws_client, username=_unique("alice"))
+    room = ws_client.post("/api/rooms", json={"name": _unique("general")}).json()
+
+    with ws_client.websocket_connect("/ws/chat") as ws:
+        ws.send_json({"type": "join", "room_id": room["id"]})
+        assert ws.receive_json()["type"] == "joined"
+
+        ws.send_json({"type": "message", "room_id": room["id"], "content": "hello"})
+        message = ws.receive_json()
+
+        ws.send_json({"type": "delete", "room_id": room["id"], "message_id": message["id"]})
+        assert ws.receive_json()["type"] == "message_deleted"
+
+        ws.send_json(
+            {
+                "type": "edit",
+                "room_id": room["id"],
+                "message_id": message["id"],
+                "content": "resurrected",
+            }
+        )
+        assert ws.receive_json() == {"type": "error", "detail": "Message not found"}
+
+        ws.send_json(
+            {
+                "type": "reaction",
+                "room_id": room["id"],
+                "message_id": message["id"],
+                "emoji": "👍",
+            }
+        )
+        assert ws.receive_json() == {"type": "error", "detail": "Message not found"}
+
+
+def test_delete_fans_out_across_instances(ws_client_factory):
+    instance1 = ws_client_factory()
+    instance2 = ws_client_factory()
+
+    alice = _register_ws(instance1, _unique("alice"))
+    room = instance1.post("/api/rooms", json={"name": _unique("general")}).json()
+
+    bob = _register_ws(instance2, _unique("bob"))
+    instance2.post(f"/api/rooms/{room['id']}/join")
+
+    with instance2.websocket_connect("/ws/chat") as bob_ws:
+        bob_ws.send_json({"type": "join", "room_id": room["id"]})
+        assert _recv(bob_ws)["type"] == "joined"
+
+        with instance1.websocket_connect("/ws/chat") as alice_ws:
+            alice_ws.send_json({"type": "join", "room_id": room["id"]})
+            assert alice_ws.receive_json()["type"] == "joined"
+            alice_ws.send_json({"type": "message", "room_id": room["id"], "content": "hi"})
+            message = alice_ws.receive_json()
+            assert _recv(bob_ws)["type"] == "message"
+
+            alice_ws.send_json(
+                {"type": "delete", "room_id": room["id"], "message_id": message["id"]}
+            )
+            assert alice_ws.receive_json()["type"] == "message_deleted"
+
+            deleted = _recv(bob_ws)
+            assert deleted == {"type": "message_deleted", "id": message["id"], "room_id": room["id"]}
+
+
+def test_delete_removes_underlying_image_from_disk(ws_client):
+    username = _unique("alice")
+    _register_ws(ws_client, username=username)
+    room = ws_client.post("/api/rooms", json={"name": _unique("general")}).json()
+
+    upload = ws_client.post(
+        f"/api/rooms/{room['id']}/images",
+        files={"file": ("test.png", _png_bytes(), "image/png")},
+    ).json()
+    image_id = upload["id"]
+
+    with ws_client.websocket_connect("/ws/chat") as ws:
+        ws.send_json({"type": "join", "room_id": room["id"]})
+        assert ws.receive_json()["type"] == "joined"
+
+        ws.send_json({"type": "message", "room_id": room["id"], "image_id": image_id})
+        message = ws.receive_json()
+        assert message["image_id"] == image_id
+
+        # Confirm the image actually serves before deleting, so a false
+        # pass (it was never reachable to begin with) can't hide as a true
+        # one below.
+        get_resp = ws_client.get(f"/api/rooms/{room['id']}/images/{image_id}")
+        assert get_resp.status_code == 200
+
+        ws.send_json({"type": "delete", "room_id": room["id"], "message_id": message["id"]})
+        assert ws.receive_json()["type"] == "message_deleted"
+
+    # The image is gone -- both the DB row (via the now-404ing serve
+    # endpoint) and, per #53's "delete the file too" choice, the file
+    # actually unlinked from disk (not just detached and orphaned).
+    get_resp = ws_client.get(f"/api/rooms/{room['id']}/images/{image_id}")
+    assert get_resp.status_code == 404