Absolutely! Stackdriver (now rebranded as Google Cloud Monitoring + Cloud Logging) can fully cover all three of your monitoring needs for your GAE + GCS setup. Let’s break down how to configure each part clearly:

First off, Google App Engine automatically sends OAuth-related events to Cloud Logging (this is enabled by default for standard environment apps). You’ll want to focus on logs tagged with oauth or auth, specifically entries related to OAuth2Authentication or token validation steps.

• Create logs-based metrics to track critical events:
  • Count of successful OAuth logins (filter logs for 200 status codes and success messages like "Authentication completed")
  • Count of failed authentication attempts (filter for 401/403 errors or messages like "Invalid token" or "Unauthorized")
• Set up alerting policies for unusual patterns—like a sudden spike in failed attempts (possible brute-force attack) or a drop in successful logins (indicating a potential auth service issue).

Monitoring token expiry and active sessions requires a mix of app-level logging and built-in Cloud Monitoring metrics:

• Track expiry events: Add structured logging to your app code every time a user’s token is rejected due to expiry, or when you detect an upcoming expiry. Include details like user ID, token type, and expiry timestamp in these logs. Then create a logs-based metric to count these events over time.
• Leverage built-in IAM metrics: Cloud Monitoring includes metrics like iam.googleapis.com/oauth_token/invalid which counts invalid token requests—including those that fail due to expiry. You can filter this metric to focus on your app’s traffic.
• Calculate active sessions: Combine successful login logs with logout/expiry events to create a custom metric representing active users. Visualize this on a Cloud Monitoring dashboard to keep an eye on session health.

GCS has robust built-in monitoring and logging tools to track user-specific API activity:

• Use out-of-the-box GCS metrics: Cloud Monitoring provides metrics like storage.googleapis.com/api/request_count (break this down by API method: GetObject, PutObject, DeleteObject), request_latency, and error_count. If your app passes the authenticated user’s identity in GCS API requests, you can filter these metrics by user to track individual interactions.
• Enable GCS access logs: Turn on access logging for your buckets (via Cloud Console or the gsutil logging set on -b [logging-bucket] [target-bucket] command). These logs include granular details: authenticated user, request type, object name, response status, and more. Import these logs into Cloud Logging, create logs-based metrics, and build dashboards to visualize user-specific GCS activity.
• Set up alerts for abnormal behavior—like a single user making an unusually high number of delete requests, or repeated failed attempts to access restricted objects.

• Start with the Cloud Monitoring for App Engine guide, which covers enabling logging/metrics for GAE, creating custom metrics, and setting up alerts.
• The GCS Monitoring & Logging documentation walks through enabling access logs, using built-in metrics, and analyzing API activity.
• For OAuth-specific monitoring, check the IAM OAuth Token Metrics section in the Cloud Monitoring docs—it details all available metrics for token validation and usage.

Let me know if you need help refining any of these configurations—I’m happy to dive deeper into specific steps!

内容的提问来源于stack exchange，提问作者SubZeno