[xwiki-devs] [PROPOSAL] How to translate logs

Hi devs, A missing peace of Extension Manager UI is the fact that the log associated to a task is not translatable right now. So I'm working on making easy to translation log in general since that's actually what EM is displaying: just plain standard slf4j log (see http://jira.xwiki.org/browse/XCOMMONS-304). = Possibilities = Here are several possibilities: 1) translate the message before giving it to the log event, so it's up to the log producer to translation its log based on the context language 2) provide an additional translation key along with what will now be the default message when logging 3) generate a translation key based on the default message Here is what I think of those: 1) is a bit better for the user than the current situation but not that much, instead of behind stuck with english he will be stuck with another language with stored logs. It also make anyone that produce log depends on many things to actually translate that message so it's a -1 for me 3) sounds very fragile = The actual proposal = Here is a detailed proposal for 2): The idea would be to pass the translation key using slf4j Marker API. We introduce a TranslationMarker which implements Marker and is passed with the log when you want to associated a translation key to a log. Here is an example: producer (for example the install job): "" logger.error(TranslationMarker.getMarker("some.translation.key"), "A default error message generally in english with a [{}]", "parameter", exception) "" displayer (for example the Extension Manager UI, should be a logging module UI element btw reused by Extension Manager ;)): "" #set($translationKey = $logEvent.marker.translationKey) "" WDYT ? -- Thomas Mortagne