Add automatic TLS certificate check+download

Author: Corentin

snippet.py

@@ -1,7 +1,20 @@
+import os
+from pathlib import Path
+import urllib.request
+
 from pyarrow import flight
 
-client = flight.connect('grpc+tls://flight.spiceai.io')
 
+# Check for gRPC required Google certificate file
+tls_root_certs = None
+if not Path('/usr', 'share', 'grpc', 'roots.pem').exists():
+    env_name = 'GRPC_DEFAULT_SSL_ROOTS_FILE_PATH'
+    if env_name in os.environ and not Path(os.environ[env_name]).exists():
+        print('Downloading gRPS root certificates')
+        tls_root_certs = './roots.pem'
+        urllib.request.urlretrieve('https://pki.google.com/roots.pem', tls_root_certs)
+
+client = flight.connect('grpc+tls://flight.spiceai.io', tls_root_certs=tls_root_certs)
 headers = [client.authenticate_basic_token('', 'API_KEY')]
 options = flight.FlightCallOptions(headers=headers)