implement cron job for resign_whitelist in main.py

server/src/main.py

@@ -137,6 +137,8 @@ async def fastapi_lifespan(app: FastAPI):
         scheduler.start()
         # Run housekeeping every minute
         scheduler.add_job(housekeeping, CronTrigger.from_crontab("* * * * *"))
+        # Run resign_whitelist daily
+        scheduler.add_job(resign_whitelist, CronTrigger.from_crontab("0 0 * * *"))
         yield
     finally:
         scheduler.shutdown()
@@ -145,6 +147,17 @@ async def fastapi_lifespan(app: FastAPI):
 fastapi_app = WATcloudFastAPI(logger=logger, lifespan=fastapi_lifespan)
 transaction_lock = Lock()
 
+def resign_whitelist():
+    """
+    Function to run the cvmfs_server resign command.
+    """
+    logger.info("Running cvmfs_server resign")
+    res = subprocess.run(["cvmfs_server", "resign"], check=True)
+    if res.returncode != 0:
+        logger.error(f"Failed to run cvmfs_server resign (exit code: {res.returncode})")
+    else:
+        logger.info("Successfully ran cvmfs_server resign")
+
 @fastapi_app.post("/repos/{repo_name}")
 async def upload(repo_name: str, file: UploadFile, overwrite: bool = False, ttl_s: int = DEFAULT_TTL_S):
     logger.info(f"Uploading file: {file.filename} (content_type: {file.content_type}, ttl_s: {ttl_s}) to repo: {repo_name}")