Formatter extension for printing CEL expressions (proto)

This extension has the qualified name envoy.formatter.cel


This extension is functional but has not had substantial production burn time, use only with this caveat.

This extension is intended to be robust against both untrusted downstream and upstream traffic.


This extension extends and can be used with the following extension category:

This extension must be configured with one of the following type URLs:

CEL formatter extension implements CEL command operator that evaluates configured symbolic Common Expression Language expressions to generate an access log.

See here for more information on access log configuration.

%CEL(EXPRESSION):Z% Expressions are based on the set of Envoy attributes. Expression errors are considered -. Z is an optional parameter denoting string truncation up to Z characters long.

Examples: - %CEL(response.code)% - %CEL(connection.mtls)% - %CEL(request.headers['x-envoy-original-path']):10% - %CEL(request.headers['x-log-mtls'] || request.url_path.contains('v1beta3'))%


[extensions.formatter.cel.v3.Cel proto]

Configuration for the CEL formatter.