Log configuration

Rails logging uses logback. For documentation, see https://logback.qos.ch/manual/index.html .

The production configuration file is rails/src/main/resources/logback.xml. Currently, both file (18xx.log) and console (stdout) logging are defined.

For development and testing purposes, developers can create an overriding configuration file named logback-test.xml, which should be stored somewhere in the classpath (for instance main/resources or test/resources). This file will be ignored by Git and therefore not end up in the repository, so it remains local.