Best Practices and Workarounds for Advanced Alerting and Monitoring in Sentry.io
Sentry.io provides robust tools for monitoring and alerting, but certain scenarios require advanced configurations or workarounds. This article outlines best practices for using synthetic events and custom evaluators, as well as workarounds for alerting on Content Security Policy (CSP) violations.
Best Practices for Synthetic Events
When using synthetic events and custom evaluators instead of metric monitors, follow these best practices to ensure effective monitoring:
Bound Synthetic Event Volume: Synthetic events count toward your error event quota, so it’s essential to keep their volume within reasonable limits.
Use Stable Fingerprints: Assign a stable fingerprint to each endpoint to ensure consistent mapping to issues. This helps in tracking and resolving issues effectively.
Plan for Regressions: If you resolve issues upon recovery, ensure that subsequent breaches with the same fingerprint reopen or regress the existing issue. Use a plain Resolve for this: resolving "in the next release" or "in a release" only regresses the issue when a later event comes from a newer release, so repeat breaches from the same release will not reopen it. Configure alert rules and workflows to handle these regressions appropriately.
Comprehensive Query Strategy: Ensure your query strategy evaluates all relevant controllers. For example, if using /events-timeseries/ with topEvents=10, split scopes as needed to cover all controllers.
Workarounds for CSP Violations
Errors metric monitors in Sentry do not natively count CSP events. To alert on CSP violations, consider the following workarounds:
Emit Structured Logs or Metrics: For each CSP violation, emit a structured log or increment an application metric. Then, monitor the log count or metric in Sentry.
Send Tagged Events: Use the Sentry SDK to send a separate error event tagged with csp_violation:true. Configure an Errors metric monitor filtered on this tag to track CSP violations.
Important Notes:
These workarounds require additional instrumentation in your application.
They will generate additional data and cannot retroactively count existing CSP reports.
General Recommendations for Custom Monitoring
Always evaluate the trade-offs of additional instrumentation, such as increased data volume and complexity.
Regularly review and optimize your alerting and monitoring configurations to align with your application’s needs.
By following these best practices and implementing the suggested workarounds, you can enhance your monitoring and alerting capabilities in Sentry.io, even in complex scenarios.