Update sync.py

Author: aditigopalan

google-sheet-sync/sync.py

@@ -4,9 +4,25 @@
 from datetime import datetime
 from google.oauth2.service_account import Credentials
 from googleapiclient.discovery import build
-from github import Github
+from github import Github, GithubException
 
 def authenticate_google(credentials_file):
+     """
+    Authenticate and create a Google Sheets API client.
+
+    This function reads a Google service account credentials file to authenticate
+    and build a client for accessing the Google Sheets API. 
+    Args:
+        credentials_file (str): The path to the Google service account JSON credentials file. 
+        GOOGLE_CREDENTIALS stored securely as GitHub Secret on the mc2-centerbot account
+
+    Returns:
+        googleapiclient.discovery.Resource: An authenticated client object for interacting
+        with the Google Sheets API.
+    
+    Raises:
+        google.auth.exceptions.GoogleAuthError: If authentication fails due to invalid or missing credentials.
+    """
     creds = Credentials.from_service_account_file(credentials_file, scopes=["https://www.googleapis.com/auth/spreadsheets.readonly"])
     return build('sheets', 'v4', credentials=creds)
 
@@ -62,24 +78,41 @@ def main():
     # Ensure branch exists
     try:
         repo.get_branch(branch_name)
-    except Exception:
+    except GithubException as e:
+    # Check if the error is due to a non-existent branch
+    if e.status == 404:
         main_branch = repo.get_branch("main")
         repo.create_git_ref(ref=f"refs/heads/{branch_name}", sha=main_branch.commit.sha)
+    else:
+        raise
 
-    # Commit changes to the branch
+# Commit changes to the branch
+try:
     try:
-        contents = None
-        try:
-            contents = repo.get_contents(file_path, ref=branch_name)
-        except Exception:
-            pass
-        if contents:
-            repo.update_file(file_path, "Update CSV file from Google Sheet", csv_content, contents.sha, branch=branch_name)
+        # Attempt to get the file contents
+        contents = repo.get_contents(file_path, ref=branch_name)
+        # Update the file if it exists
+        repo.update_file(
+            file_path, 
+            "Update CSV file from Google Sheet", 
+            csv_content, 
+            contents.sha, 
+            branch=branch_name
+        )
+    except GithubException as e:
+        # If the file doesn't exist (404), create it
+        if e.status == 404:
+            repo.create_file(
+                file_path, 
+                "Create CSV file from Google Sheet", 
+                csv_content, 
+                branch=branch_name
+            )
         else:
-            repo.create_file(file_path, "Create CSV file from Google Sheet", csv_content, branch=branch_name)
-    except Exception as e:
-        print(f"Error committing changes: {e}")
-
+            raise  # Re-raise other exceptions
+except Exception as e:
+    print(f"Error committing changes: {e}")
+    
     # Create or reuse PR
     try:
         open_prs = repo.get_pulls(state="open", head=f"{repo.owner.login}:{branch_name}")
@@ -94,4 +127,4 @@ def main():
         print(f"Error creating PR: {e}")
 
 if __name__ == "__main__":
-    main()
+    main()