When you’re testing your workflows, you’re often looking at the console log. I find it really useful to colourise the output so that errors and such are easily recognisable. We can do this quite easily by including a couple of additional jars into the interlok runtime and having a custom pattern.

Log4j2 colourisation automatically works on Unix style terminals (Linux / Mac for instance) so you don’t need to do anything special; however on Windows, you need to include the jansi artefact which handles ANSI escape code in your console, so you basically need to include that as a dependency in your dependency management.

<dependency org="org.fusesource.jansi" name="jansi" rev="1.17.1" conf="runtime->default"/>

And then it’s just a case of using the highlight pattern in your console appender.

<Console name="Console" target="SYSTEM_OUT">
  <PatternLayout>

    <Pattern>%highlight{%d [%t] %-5level: %msg%n%throwable}{FATAL=bright white, ERROR=bright red, WARN=yellow, INFO=magenta, DEBUG=green, TRACE=cyan}</Pattern>

  </PatternLayout>
  <filters>
    <ThresholdFilter level="TRACE"/>
  </filters>
</Console>

Note that if you are on Windows and using log4j2 > 2.9.1, then you need to explicitly enable jansi (use -Dlog4j.skipJansi=false) when starting up Interlok; alternatively have a log4j2.component.properties file on the class path that contains the same setting e.g.

$ cat config/log4j2.component.properties
log4j.skipJansi=false