Logging — org.onyxplatform/onyx 0.14.5-SNAPSHOT

This chapter details how to inspect and modify the logs that Onyx produces.

Timbre

Onyx uses Timbre for logging.

By default, all Onyx output is logged to a file called onyx.log in the same directory as where the peer or coordinator jar is executing. The logging configuration can be overridden completely, see below.

Onyx’s default logging configuration writes all WARN and FATAL messages to standard out, also.

Overriding the log file name and path

In order to override the log file location add :onyx.log/file to both the environment config sent into start-env as well as the peer config sent into start-peer-group.

Both relative and absolute paths are supported by Timbre.

Overriding the Timbre log config

Similarly, to override the full Timbre log config map, construct the Timbre configuration and add it to both the environment and peer config maps under the :onyx.log/config key. Note that the onyx.log/config map will be merged with the existing Timbre configuration rather than replacing it completely. In practice this means that extra configuration must be sent in to, for example, disable appenders that are enabled by default. See the examples below.

Examples

The following example simply changes the output file.

(let [log-config {:onyx.log/file "/var/log/onyx.log"}
      peer-config (merge my-peer-config log-config)
      env-config (merge my-env-config log-config)]
  (onyx.api/start-env env-config)
  (onyx.api/start-peer-group peer-config)

  ;; ...
  )

This example uses Timbre to redirect Onyx logs into the regular Java logging system using the log-config library.

(require '[com.palletops.log-config.timbre.tools-logging :as tl])
(let [log-config {:onyx.log/config {:appenders
                                    {:spit {:enabled? false}
                                     :standard-out {:enabled? false}
                                     :rotor {:enabled? false}
                                     :jl (tl/make-tools-logging-appender
                                          {:enabled? true
                                           :fmt-output-opts {:nofonts? true}})}
                                    :min-level :trace}}
      peer-config (merge my-peer-config log-config)
      env-config (merge my-env-config log-config)]
  (onyx/start-env env-config)
  (onyx/start-peer-group peer-config)

  ;; ...
  )

If you already have timbre logging configured somewhere in your code base, you can specify :onyx.log/config {} to ensure your settings remain unchanged. In effect, this simply merges in the empty map into whatever settings you may have already specified for logging.

(let [log-config {:onyx.log/config {}}
      peer-config (merge my-peer-config log-config)
      env-config (merge my-env-config log-config)]
  (onyx.api/start-env env-config)
  (onyx.api/start-peer-group peer-config)

  ;; ...
  )

See the Timbre example configuration for more information on valid values for the :onyx.log/config map.