title: How read Environment variable in solr.properties
body: <p>I'm triying read a Environment Variable in a solr.properties file, the solr is running in a docker container and my docker-compose look:</p>
  
  <pre><code>solr:
  
    environment:
     - DB_NAME="xxxx"
  </code></pre>
  
  <p>My solr.properties is in /var/solr/ and i tried read de Environment Variable how:</p>
  
  <pre><code>jdbc.url=jdbc:mysql://localhost:3306/${DB_NAME}?zeroDateTimeBehavior=convertToNull&amp;amp;useUnicode=false
  
  jdbc.url=jdbc:mysql://localhost:3306/${env.DB_NAME}?zeroDateTimeBehavior=convertToNull&amp;amp;useUnicode=false
  
  jdbc.url=jdbc:mysql://localhost:3306/${env:DB_NAME}?zeroDateTimeBehavior=convertToNull&amp;amp;useUnicode=false
  
  
  </code></pre>
  
  <p>I'm starting with Docker, any idea ?</p>