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spring-bootlogback

Empty Default String for Property in logback.xml

Our project structure regarding the logback.xmls looks like this:

src\main\resources\logback.xml
src\main\resources\config\dev\logback.xml
src\main\resources\config\sjngm\dev\logback.xml
src\main\resources\config\int\logback.xml
src\main\resources\config\local\logback.xml
src\main\resources\config\prod\logback.xml

where the first one references to the environment specific one:

<?xml version="1.0" encoding="UTF-8"?>
<configuration scan="true" scanPeriod="30 seconds">
  <contextName>sjngm</contextName>
  <jmxConfigurator />
  <include resource="config/${extra}${env:-local}/logback.xml" />
</configuration>

Note that extra is not defined most of the times, which is why used this for a while:

  <include resource="config/${extra:-}${env:-local}/logback.xml" />

This stopped working at one point, can't remember which version of logback. So we changed it to

  <include resource="config/${extra:-./}${env:-local}/logback.xml" />

which also worked for quite a while.

Now we switched to Spring Boot 1.5.4 (contains logback-classic 1.1.11 and logback-core 1.1.11) and it stopped working again. The latest error message is:

11:08:15,020 |-WARN in ch.qos.logback.core.joran.action.IncludeAction - Could not find resource corresponding to [config/./local/logback.xml]

If I go back to

  <include resource="config/${extra:-}${env:-local}/logback.xml" />

the message is

11:19:28,778 |-WARN in ch.qos.logback.core.joran.action.IncludeAction - Could not find resource corresponding to [config/extra_IS_UNDEFINEDlocal/logback.xml]

Note that logback still uses "local" as a default string for env, so not all is broken.

What do I do now? Basically I want to tell logback that I want an empty string where extra would be.

Solution

  • This also doesn't work:

    <property name="defaultExtra" value="" />
<include resource="config/${extra:-${defaultExtra}}${env:-local}/logback.xml" />

    as an empty string seems to always result in an undefined property.

    The only working thing I can come up with is this:

    <if condition='isDefined("extra")'>
  <then>
    <include resource="config/${extra}${env:-local}/logback.xml" />
  </then>
  <else>
    <include resource="config/${env:-local}/logback.xml" />
  </else>
</if>

    plus this into the pom.xml:

    <dependency>
  <groupId>org.codehaus.janino</groupId>
  <artifactId>janino</artifactId>
</dependency>

    Isn't this nice?! So why did they have to break what was working nicely???