better error when GCP not set

Author: felix-red-panda

src/genesys/generate.py

@@ -51,10 +51,13 @@ def main(config: GenerateConfig):
 
     # Initialize components
     log("[cyan] Configuring output path and gcp bucket...[/]")
+if config.gcp_bucket is not None:
+        gcp_credentials = os.environ.get("GCP_CREDENTIALS_BASE64")
+        assert gcp_credentials is not None, "the GCP_CREDENTIALS_BASE64 environment variable is not set"
     if not os.path.exists(config.path_output):
         os.makedirs(config.path_output)
     gcp_bucket = (
-        GcpBucket(config.gcp_bucket, os.environ.get("GCP_CREDENTIALS_BASE64"))
+        GcpBucket(config.gcp_bucket, gcp_credentials)
         if config.gcp_bucket is not None
         else None
     )