.. _config_access_log_dynamic_modules:

Dynamic Modules Access Logger

• :ref:v3 API reference <envoy_v3_api_msg_extensions.access_loggers.dynamic_modules.v3.DynamicModuleAccessLog>

The Dynamic Modules Access Logger allows you to write access loggers in a dynamic module. This can be used to implement custom logging behavior, such as:

• Sending logs to custom backends.
• Custom log formatting and aggregation.
• Real-time metrics extraction from access logs.
• Integration with proprietary logging systems.

The logger receives completed request information including:

• Request and response headers (and trailers).
• Response code and details.
• Response flags (indicating errors, timeouts, etc.).
• Timing information (request duration, upstream latency, etc.).
• Byte counts (request/response sizes).
• Upstream information (cluster, host, connection details).
• TLS information (versions, certificates).
• Tracing information (trace ID, span ID).
• Dynamic metadata and filter state.

Example Configuration

.. code-block:: yaml

access_log:

• name: envoy.access_loggers.dynamic_modules typed_config: "@type": type.googleapis.com/envoy.extensions.access_loggers.dynamic_modules.v3.DynamicModuleAccessLog dynamic_module_config: name: my_logger logger_name: json_logger logger_config: "@type": type.googleapis.com/google.protobuf.Struct value: output_path: "/var/log/envoy/access.json" buffer_size: 100

For more details on dynamic modules, see the :ref:architecture overview <arch_overview_dynamic_modules>.