title: Where to store Android KeyStore file for CirlceCi build?
body: <p>I am trying to configure continuous integration build for my Android app.
  I use CircleCi platform for it. 
  Now I store my apps Keystore.jks file locally, but CircleCi needs it to sign my app.
  How can I achieve that without storing the file on my git repository? Or maybe I shouldn't be concerned about that while the repository is private?</p>
  
  <p>My gradle signing configs:</p>
  
  <pre><code>signingConfigs {
      if (System.getenv("CIRCLECI")) {
          release {
              keyAlias '****'
              keyPassword '****'
              storeFile file(System.getenv("******"))
              storePassword '****'
          }
      }else{
          release {
               ...
          }
      }
  }
  </code></pre>
  
  <p>My circle.yml :</p>
  
  <pre><code>general:
      artifacts:
          - /home/ubuntu/my-app/app/build/outputs/apk/
  machine:
    environment:
      ANDROID_HOME: /usr/local/android-sdk-linux
  dependencies:
    override:
       - chmod +x gradlew
  test:
    override:
      - ./gradlew assemble
  </code></pre>
  
  <p>I tried to save the keystore file on CircleCi as environmental variable but it isn't working, my build fails with exception:</p>
  
  <pre><code>&gt; Execution failed for task ':app:validateSigningDemoRelease'.
  &gt; &gt; Keystore file /home/ubuntu/my-app/app/  HERE_IS_THE_KEYSTORE not found for signing config 'release'.
  </code></pre>
  
  <p>Unsigned and debug builds finish with success. </p>
  
  <p>I'm also open to use any different ci platform if you suggest something else.</p>
  
  <p>Thanks in advance for every advice! </p>