feat: implementazione V1 - app.py, Dockerfile, docker-compose, .env.example, requirements

2026-04-24 13:09:46 +02:00
parent 96441e5e10
commit 10ed6f6c2f
7 changed files with 255 additions and 24 deletions
@@ -0,0 +1,189 @@
+"""
+supabase-pinger
+---------------
+Servizio long-running che esegue periodicamente una query di keep-alive
+verso un database Supabase/PostgreSQL per evitarne la sospensione automatica
+nel free tier.
+
+Configurazione: file .env (vedi .env.example)
+"""
+
+import logging
+import os
+import signal
+import sys
+import time
+
+import psycopg2
+from dotenv import load_dotenv
+
+# ---------------------------------------------------------------------------
+# Logging
+# ---------------------------------------------------------------------------
+
+logging.basicConfig(
+    level=logging.INFO,
+    format="%(asctime)s  %(levelname)-8s  %(message)s",
+    datefmt="%Y-%m-%d %H:%M:%S",
+    stream=sys.stdout,
+)
+log = logging.getLogger("supabase-pinger")
+
+# ---------------------------------------------------------------------------
+# Shutdown ordinato
+# ---------------------------------------------------------------------------
+
+_shutdown = False
+
+
+def _handle_signal(signum, _frame):
+    global _shutdown
+    log.info("Segnale di arresto ricevuto (%s). Chiusura in corso...", signum)
+    _shutdown = True
+
+
+signal.signal(signal.SIGTERM, _handle_signal)
+signal.signal(signal.SIGINT, _handle_signal)
+
+# ---------------------------------------------------------------------------
+# Configurazione
+# ---------------------------------------------------------------------------
+
+_REQUIRED_VARS = [
+    "SUPABASE_DB_HOST",
+    "SUPABASE_DB_PORT",
+    "SUPABASE_DB_NAME",
+    "SUPABASE_DB_USER",
+    "SUPABASE_DB_PASSWORD",
+]
+
+
+def load_config() -> dict:
+    """Carica e valida la configurazione dal file .env o dall'ambiente."""
+    load_dotenv()
+
+    missing = [v for v in _REQUIRED_VARS if not os.environ.get(v)]
+    if missing:
+        log.error(
+            "Variabili di ambiente obbligatorie mancanti: %s", ", ".join(missing)
+        )
+        sys.exit(1)
+
+    try:
+        port = int(os.environ["SUPABASE_DB_PORT"])
+    except ValueError:
+        log.error("SUPABASE_DB_PORT deve essere un numero intero.")
+        sys.exit(1)
+
+    try:
+        interval = int(os.environ.get("PING_INTERVAL_MINUTES", "4320"))
+        if interval <= 0:
+            raise ValueError
+    except ValueError:
+        log.error("PING_INTERVAL_MINUTES deve essere un numero intero positivo.")
+        sys.exit(1)
+
+    return {
+        "host": os.environ["SUPABASE_DB_HOST"],
+        "port": port,
+        "dbname": os.environ["SUPABASE_DB_NAME"],
+        "user": os.environ["SUPABASE_DB_USER"],
+        "password": os.environ["SUPABASE_DB_PASSWORD"],
+        "query": os.environ.get("PING_QUERY", "SELECT 1;"),
+        "interval_minutes": interval,
+    }
+
+# ---------------------------------------------------------------------------
+# Keep-alive
+# ---------------------------------------------------------------------------
+
+
+def ping(cfg: dict) -> bool:
+    """
+    Apre una connessione, esegue la query di keep-alive e chiude tutto.
+    Restituisce True in caso di successo, False in caso di errore.
+    Non espone mai credenziali nei log.
+    """
+    conn = None
+    try:
+        log.info(
+            "Connessione a %s:%d/%s...",
+            cfg["host"],
+            cfg["port"],
+            cfg["dbname"],
+        )
+        conn = psycopg2.connect(
+            host=cfg["host"],
+            port=cfg["port"],
+            dbname=cfg["dbname"],
+            user=cfg["user"],
+            password=cfg["password"],
+            connect_timeout=10,
+        )
+        with conn.cursor() as cur:
+            log.info("Esecuzione query di keep-alive: %s", cfg["query"])
+            cur.execute(cfg["query"])
+        log.info("Keep-alive eseguito con successo.")
+        return True
+    except psycopg2.OperationalError as exc:
+        log.error("Errore di connessione al database: %s", exc)
+        return False
+    except psycopg2.Error as exc:
+        log.error("Errore durante l'esecuzione della query: %s", exc)
+        return False
+    finally:
+        if conn is not None:
+            try:
+                conn.close()
+            except Exception:
+                pass
+
+# ---------------------------------------------------------------------------
+# Loop principale
+# ---------------------------------------------------------------------------
+
+
+def run(cfg: dict) -> None:
+    """Loop principale del servizio."""
+    interval_seconds = cfg["interval_minutes"] * 60
+
+    log.info("=" * 60)
+    log.info("supabase-pinger avviato")
+    log.info("Host        : %s:%d/%s", cfg["host"], cfg["port"], cfg["dbname"])
+    log.info("Intervallo  : %d minuti", cfg["interval_minutes"])
+    log.info("Query       : %s", cfg["query"])
+    log.info("=" * 60)
+
+    while not _shutdown:
+        success = ping(cfg)
+
+        if not success:
+            log.warning(
+                "Keep-alive fallito. Nuovo tentativo al prossimo ciclo."
+            )
+
+        if _shutdown:
+            break
+
+        next_run = time.strftime(
+            "%Y-%m-%d %H:%M:%S",
+            time.localtime(time.time() + interval_seconds),
+        )
+        log.info("Prossima esecuzione: %s. In attesa...", next_run)
+
+        # Sleep a blocchi per rispondere rapidamente a SIGTERM/SIGINT
+        elapsed = 0
+        while elapsed < interval_seconds and not _shutdown:
+            time.sleep(min(10, interval_seconds - elapsed))
+            elapsed += 10
+
+    log.info("supabase-pinger arrestato.")
+
+
+# ---------------------------------------------------------------------------
+# Entrypoint
+# ---------------------------------------------------------------------------
+
+if __name__ == "__main__":
+    config = load_config()
+    run(config)