feat(discovery): world visit tracking endpoint with atomic play_count increment, last_played_at, and deduplication

backend/tests/test_discovery_visit_api.py

@@ -0,0 +1,164 @@
+"""API tests for world visit tracking endpoint.
+
+docs/planning/discovery.md (task 42726e60fe10).
+"""
+
+import pytest
+from fastapi.testclient import TestClient
+from sqlalchemy import select
+from sqlalchemy.ext.asyncio import async_sessionmaker, create_async_engine
+from sqlalchemy.pool import NullPool
+
+from app.config import settings
+from app.main import app
+from app.models.world import World, WorldVisibility
+from app.models.world_visit import WorldVisit
+
+
+def _register(client: TestClient, username: str) -> tuple[int, dict[str, str]]:
+    resp = client.post(
+        "/api/auth/register",
+        json={
+            "username": username,
+            "email": f"{username}@example.com",
+            "password": "secret123",
+            "date_of_birth": "1990-01-01",
+        },
+    )
+    assert resp.status_code == 201, resp.text
+    token = resp.json()["access_token"]
+    headers = {"Authorization": f"Bearer {token}"}
+    me = client.get("/api/users/me", headers=headers)
+    assert me.status_code == 200, me.text
+    return me.json()["id"], headers
+
+
+def _session_factory():
+    engine = create_async_engine(settings.DATABASE_URL, poolclass=NullPool)
+    return engine, async_sessionmaker(engine, expire_on_commit=False)
+
+
+@pytest.mark.asyncio
+async def test_visit_world_atomic_increment_authenticated():
+    client = TestClient(app)
+    owner_id, owner_headers = _register(client, "visit_owner_1")
+    visitor_id, visitor_headers = _register(client, "visitor_user_1")
+
+    # Create world
+    resp = client.post(
+        "/api/worlds/",
+        headers=owner_headers,
+        json={"name": "Neon City", "visibility": "public", "category": "Roleplay"},
+    )
+    assert resp.status_code == 201, resp.text
+    world_id = resp.json()["id"]
+
+    # Visitor visits the world
+    v_resp = client.post(
+        f"/api/discovery/worlds/{world_id}/visit",
+        headers=visitor_headers,
+    )
+    assert v_resp.status_code == 200, v_resp.text
+    data = v_resp.json()
+    assert data["play_count"] == 1
+    assert data["last_played_at"] is not None
+
+    # Verify DB state
+    engine, sf = _session_factory()
+    try:
+        async with sf() as session:
+            w = (await session.execute(select(World).where(World.id == world_id))).scalar_one()
+            assert w.play_count == 1
+            assert w.last_played_at is not None
+
+            visits = (
+                await session.execute(
+                    select(WorldVisit).where(WorldVisit.world_id == world_id)
+                )
+            ).scalars().all()
+            assert len(visits) == 1
+            assert visits[0].user_id == visitor_id
+    finally:
+        await engine.dispose()
+
+
+@pytest.mark.asyncio
+async def test_visit_world_anonymous_and_idempotency():
+    client = TestClient(app)
+    owner_id, owner_headers = _register(client, "visit_owner_2")
+
+    resp = client.post(
+        "/api/worlds/",
+        headers=owner_headers,
+        json={"name": "Space Station", "visibility": "public"},
+    )
+    world_id = resp.json()["id"]
+
+    # Anonymous visit with token
+    anon_token = "guest_token_999"
+    v_resp1 = client.post(
+        f"/api/discovery/worlds/{world_id}/visit",
+        json={"anonymous_token": anon_token},
+    )
+    assert v_resp1.status_code == 200, v_resp1.text
+    assert v_resp1.json()["play_count"] == 1
+
+    # Idempotent second call with same anonymous token
+    v_resp2 = client.post(
+        f"/api/discovery/worlds/{world_id}/visit",
+        json={"anonymous_token": anon_token},
+    )
+    assert v_resp2.status_code == 200, v_resp2.text
+    assert v_resp2.json()["play_count"] == 1
+
+    engine, sf = _session_factory()
+    try:
+        async with sf() as session:
+            visits = (
+                await session.execute(
+                    select(WorldVisit).where(WorldVisit.world_id == world_id)
+                )
+            ).scalars().all()
+            assert len(visits) == 1
+            assert visits[0].user_id is None
+            assert visits[0].anonymous_token == anon_token
+    finally:
+        await engine.dispose()
+
+
+@pytest.mark.asyncio
+async def test_visit_world_visibility_and_404():
+    client = TestClient(app)
+    owner_id, owner_headers = _register(client, "visit_owner_3")
+    other_id, other_headers = _register(client, "other_user_3")
+
+    # 404 on non-existent world
+    res_404 = client.post("/api/discovery/worlds/999999/visit", headers=owner_headers)
+    assert res_404.status_code == 404
+
+    # Private world
+    resp = client.post(
+        "/api/worlds/",
+        headers=owner_headers,
+        json={"name": "Secret World", "visibility": "private"},
+    )
+    priv_world_id = resp.json()["id"]
+
+    # Other user gets 404
+    other_res = client.post(
+        f"/api/discovery/worlds/{priv_world_id}/visit",
+        headers=other_headers,
+    )
+    assert other_res.status_code == 404
+
+    # Anonymous user gets 404
+    anon_res = client.post(f"/api/discovery/worlds/{priv_world_id}/visit")
+    assert anon_res.status_code == 404
+
+    # Owner gets 200
+    owner_res = client.post(
+        f"/api/discovery/worlds/{priv_world_id}/visit",
+        headers=owner_headers,
+    )
+    assert owner_res.status_code == 200
+    assert owner_res.json()["play_count"] == 1