logback variable substitution in kubernetes

[houssem]

Hello,

I am running a flink application cluster in standalone kubernetes mode and i a 
using logback

as a logging framework , th problem is i am not able tu use environment 
variables configured in my pod inside my logback-console.xml file .



I copied this file  from my file system while building my image.
Dockerfile:
..
COPY logback-console.xml $FLINK_HOME/conf/
..


here is my  logback-console file::

<?xml version="1.0" encoding="UTF-8"?>
<configuration>

    <logger name="com.cpm.sdf.notif" level="$LOG_LEVEL " />
     <logger name="org.cpm.flink" level="$FLINK_LOG_LEVEL" />
     <logger name="akka" level="$FLINK_LOG_LEVEL" />
     <logger name="org.apache.hadoop" level="$FLINK_LOG_LEVEL" />
     <logger name="org.apache.zookeeper" level="$FLINK_LOG_LEVEL" />
     ####Appenders####
     #file
    <appender name="file" class="ch.qos.logback.core.FileAppender">
        <file>$LOG_FILE</file>
        <encoder class="ch.qos.logback.core.encoder.LayoutWrappingEncoder">
            <layout class="net.logstash.logback.layout.LogstashLayout">
                <suffix class="ch.qos.logback.classic.PatternLayout">
                   <pattern>%n</pattern>
                </suffix>
            </layout>
         </encoder>
    </appender>

     #console
    <appender name="stdout" class="ch.qos.logback.core.ConsoleAppender">
        <!-- encoders are assigned the type
             ch.qos.logback.classic.encoder.PatternLayoutEncoder by default -->
        <encoder class="ch.qos.logback.core.encoder.LayoutWrappingEncoder">
            <layout class="net.logstash.logback.layout.LogstashLayout">
                <suffix class="ch.qos.logback.classic.PatternLayout">
                    <pattern>%n</pattern>
                </suffix>
            </layout>
        </encoder>
     </appender>

    <root level="$LOG_LEVEL">
        <appender-ref ref="file"/>
        <appender-ref ref="stdout"/>
    </root>