add GCS support to s3.py

Author: Katharine

appstore/s3.py

@@ -7,6 +7,7 @@
 
 # Try to find a way to get S3 credentials.
 session = None
+s3_endpoint = None
 
 try:
     if session is None:
@@ -15,8 +16,9 @@
         session = boto3.Session(
             aws_access_key_id = creds['Credentials']['AccessKeyId'],
             aws_secret_access_key = creds['Credentials']['SecretAccessKey'],
-            aws_session_token = creds['Credentials']['SessionToken']
+            aws_session_token = creds['Credentials'].get('SessionToken'),
         )
+        s3_endpoint = creds.get('S3Endpoint')
 except:
     pass
 
@@ -27,7 +29,7 @@ def upload_pbw(release, file):
     filename = f"{config['S3_PATH']}{release.id}.pbw"
     print(f"uploading file {file} to {config['S3_BUCKET']}:{filename}")
 
-    s3 = session.client('s3')
+    s3 = session.client('s3', endpoint_url=s3_endpoint)
     s3.upload_file(file, config['S3_BUCKET'], filename)
 
 def upload_asset(file, mime_type = None):
@@ -43,7 +45,7 @@ def upload_asset(file, mime_type = None):
         else:
             mime_type = "image/png"
 
-    s3 = session.client('s3')
+    s3 = session.client('s3', endpoint_url=s3_endpoint)
     s3.upload_file(file, config['S3_ASSET_BUCKET'], filename, ExtraArgs = {'ContentType': mime_type})
 
     return id