feat: add sessions endpoints with close mechanism

src/backend/api/routes/sessions.py

@@ -0,0 +1,37 @@
+from fastapi import APIRouter, Depends
+from starlette.responses import JSONResponse
+
+from src.backend.api.dependencies import verify_api_key
+from src.backend.db.database import get_db, list_sessions, close_session
+from src.backend.models.api import ok, fail
+
+router = APIRouter(
+    prefix="/sessions",
+    tags=["sessions"],
+    dependencies=[Depends(verify_api_key)],
+)
+
+
+async def _get_db():
+    db = await get_db()
+    try:
+        yield db
+    finally:
+        await db.close()
+
+
+@router.get("", summary="List sessions")
+async def list_all(db=Depends(_get_db)):
+    sessions = await list_sessions(db)
+    return ok(sessions)
+
+
+@router.delete("/{session_id}", summary="Close session")
+async def delete(session_id: str, db=Depends(_get_db)):
+    closed = await close_session(db, session_id)
+    if not closed:
+        return JSONResponse(
+            status_code=404,
+            content=fail("NOT_FOUND", "Session not found"),
+        )
+    return ok({"closed": True})

tests/test_api_sessions.py

@@ -0,0 +1,74 @@
+import pytest
+from httpx import AsyncClient, ASGITransport
+
+
+@pytest.fixture
+def app():
+    from src.backend.main import app
+    return app
+
+
+@pytest.fixture
+async def client(app):
+    transport = ASGITransport(app=app)
+    async with AsyncClient(
+        transport=transport,
+        base_url="http://test",
+        headers={"X-Api-Key": "test-key-12345"},
+    ) as ac:
+        yield ac
+
+
+@pytest.fixture
+async def topic_id(client):
+    resp = await client.post(
+        "/api/topics",
+        json={"name": "sessions-test", "system_prompt": "Test prompt."},
+    )
+    return resp.json()["data"]["id"]
+
+
+@pytest.mark.asyncio
+async def test_list_sessions_empty(client):
+    resp = await client.get("/api/sessions")
+    assert resp.status_code == 200
+    assert resp.json()["data"] == []
+
+
+@pytest.mark.asyncio
+async def test_list_sessions_with_data(client, topic_id):
+    resp1 = await client.post(
+        "/api/requests",
+        json={"prompt": "First", "topic_id": topic_id, "session_id": "new"},
+    )
+    session_id = resp1.json()["data"]["session_id"]
+
+    await client.post(
+        "/api/requests",
+        json={"prompt": "Second", "topic_id": topic_id, "session_id": session_id},
+    )
+
+    resp = await client.get("/api/sessions")
+    assert resp.status_code == 200
+    sessions = resp.json()["data"]
+    assert len(sessions) == 1
+    assert sessions[0]["session_id"] == session_id
+    assert sessions[0]["request_count"] == 2
+
+
+@pytest.mark.asyncio
+async def test_delete_session(client, topic_id):
+    resp1 = await client.post(
+        "/api/requests",
+        json={"prompt": "Hello", "topic_id": topic_id, "session_id": "new"},
+    )
+    session_id = resp1.json()["data"]["session_id"]
+
+    resp = await client.delete(f"/api/sessions/{session_id}")
+    assert resp.status_code == 200
+
+    resp = await client.post(
+        "/api/requests",
+        json={"prompt": "Again", "topic_id": topic_id, "session_id": session_id},
+    )
+    assert resp.status_code == 410