feat: add FastAPI feedback backend

feedback-api/database.py

@@ -0,0 +1,57 @@
+import aiosqlite
+
+DB_PATH = "feedback.db"
+
+
+async def init_db():
+    async with aiosqlite.connect(DB_PATH) as db:
+        await db.execute("""
+            CREATE TABLE IF NOT EXISTS feedbacks (
+                id INTEGER PRIMARY KEY AUTOINCREMENT,
+                url TEXT NOT NULL,
+                choice TEXT NOT NULL CHECK(choice IN ('yes', 'no')),
+                timestamp TEXT NOT NULL,
+                ip_hash TEXT NOT NULL,
+                created_at TEXT NOT NULL DEFAULT (datetime('now'))
+            )
+        """)
+        await db.execute("""
+            CREATE INDEX IF NOT EXISTS idx_feedbacks_ip_hash
+            ON feedbacks(ip_hash, created_at)
+        """)
+        await db.commit()
+
+
+async def add_feedback(ip_hash: str, url: str, choice: str, timestamp: str):
+    async with aiosqlite.connect(DB_PATH) as db:
+        await db.execute(
+            "INSERT INTO feedbacks (url, choice, timestamp, ip_hash) VALUES (?, ?, ?, ?)",
+            (url, choice, timestamp, ip_hash),
+        )
+        await db.commit()
+
+
+async def check_rate_limit(ip_hash: str, limit: int = 5, window_seconds: int = 3600) -> bool:
+    async with aiosqlite.connect(DB_PATH) as db:
+        cursor = await db.execute(
+            "SELECT COUNT(*) FROM feedbacks WHERE ip_hash = ? AND created_at > datetime('now', ?)",
+            (ip_hash, f"-{window_seconds} seconds"),
+        )
+        row = await cursor.fetchone()
+        return row[0] >= limit
+
+
+async def get_stats() -> dict:
+    async with aiosqlite.connect(DB_PATH) as db:
+        cursor = await db.execute("SELECT COUNT(*) FROM feedbacks")
+        total = (await cursor.fetchone())[0]
+
+        cursor = await db.execute("SELECT choice, COUNT(*) FROM feedbacks GROUP BY choice")
+        rows = await cursor.fetchall()
+        counts = {row[0]: row[1] for row in rows}
+
+        return {
+            "total": total,
+            "yes": counts.get("yes", 0),
+            "no": counts.get("no", 0),
+        }