title: Firebase: pause/resume file upload
body: <p>Here is what I found on the internet how to handle upload progress to the Firebase Storage. </p>
  
  <pre><code>uploadTask.on('state_changed', function(snapshot){
      // Observe state change events such as progress, pause, and resume
      // Get task progress, including the number of bytes uploaded and the total number of bytes to be uploaded
      var progress = (snapshot.bytesTransferred / snapshot.totalBytes) * 100;
      console.log('Upload is ' + progress + '% done');
      switch (snapshot.state) {
        case firebase.storage.TaskState.PAUSED: // or 'paused'
          console.log('Upload is paused');
          break;
        case firebase.storage.TaskState.RUNNING: // or 'running'
          console.log('Upload is running');
          break;
      }
    }, function(error) {
      // Handle unsuccessful uploads
    }, function() {
      // Handle successful uploads on complete
      // For instance, get the download URL: https://firebasestorage.googleapis.com/...
      var downloadURL = uploadTask.snapshot.downloadURL;
    });
  }
  </code></pre>
  
  <p>This code contains snapshot with "Pause" state value. What does this mean? Does this mean I can pause my upload and resume it in any time later on? Does somebody have any examples how to do that? </p>