Logs¶

Structured logs¶

On Google Cloud, if you use structured logging, your entries can be filtered and inspected much more powerfully than if you log in plain text.

Django has its own default logging configuration, and some tweaking is needed to make sure the information is captured in a structured way. Notice particularly that the django and django.server modules have specific setups to record, for example, request-level information.

django-gcp provides django_gcp.logs.GoogleStructuredLogsHandler, which adds Django-specific behaviour to the Google StructuredLogHandler used under the hood. It enriches the httpRequest field of a log entry where the record carries request information:

• Entries from the django.server logger (the development server's request log) gain the request method, URL, protocol, status, response size and remote IP. The URL for these entries is the request path rather than an absolute URL, because that is all the development server records.
• Entries whose record carries a Django HttpRequest — as the django.request logger attaches for 4xx and 5xx responses — gain the request method, URL, protocol, remote IP, user agent, referer and status.

Request context and trace correlation¶

Google's logging library can attach request and trace information to every log entry emitted while handling a request, not only the request log entries described above. To enable this, add Google's RequestMiddleware to your MIDDLEWARE setting:

MIDDLEWARE = [
    "google.cloud.logging_v2.handlers.middleware.RequestMiddleware",
    # ... your other middleware ...
]

With the middleware installed, each entry logged during a request infers httpRequest data (method, URL, user agent and protocol) from that request. Trace context is read from the traceparent or X-Cloud-Trace-Context request headers — which Cloud Run and Cloud Load Balancing set automatically — and populates the entry's trace, spanId and traceSampled fields, so all entries for one request can be grouped and filtered together in the Logs Explorer.

Error Reporting¶

This is not the same thing as structured logging.

If you use Google Cloud Error Reporting (as opposed to Sentry or similar), django-gcp provides a handler enabling you to send errors and exceptions directly from Django. You can then configure Error Reporting as you wish — for example to track unresolved errors, email teams, or connect issue trackers.

django-gcp provides django_gcp.logs.GoogleErrorReportingHandler to do this. You need to set the GCP_ERROR_REPORTING_SERVICE_NAME value in your settings.py.