title: CVAT (computer vision annotation tool) export impossible
body: <p>I'm using <a href="https://github.com/opencv/cvat" rel="nofollow noreferrer">cvat</a> for segmentation annotation and am very impressed by it. However, it seems that I am unable to export my annotated data set. Upon loading the tasks page (<a href="http://localhost:7080/tasks/1" rel="nofollow noreferrer">http://localhost:7080/tasks/1</a>), I receive the error message:</p>
  
  <pre><code>Could not get formats from the server. Error: Network error.
  </code></pre>
  
  <p>From the developer console i can see that several requests fail upon </p>
  
  <pre><code>localhost:8080/auto_annotation/meta/get
  localhost:8080/tensorflow/annotation/meta/get
  localhost:8080/tensorflow/segmentation/meta/get
  localhost:8080/analytics/app/kibana
  </code></pre>
  
  <p>All these return 404. And finally one which is probably causing the error message</p>
  
  <pre><code>localhost:8080/api/v1/server/dataset/formats
  </code></pre>
  
  <p>Where no specific eror code is displayed.</p>
  
  <p>My issue is that when trying to "Export as a dataset", no options to download appear. The button does nothing.</p>
  
  <p>I am very new to docker and I don't know whether the issue can be caused by my docker setup or the installation of cvat itself.</p>
  
  <p>For the same reason I didn't know I had to run the container with a volume and so now I am in rist of losing my work.</p>
  
  <p>So far I have tried to commit the running docker container, save it as tarball, and moving it to another computer with the same cvat installation, where exporting worked before. However, I receive a similar error and not even the login page works.</p>
  
  <p>'<a href="http://localhost:8080/api/v1/users/self" rel="nofollow noreferrer">http://localhost:8080/api/v1/users/self</a>', status: (failed), type: xhr, initiator: xhr.js:160</p>
  
  <p>I have also tried to explore the exported image with bash, but I cannot seem to find any saved data of the annotations anywhere.</p>
  
  <p>If I rebuild (<code>docker-compose build</code>), as described in the installation guide, will my data get lost?</p>
  
  <p>Is there any other way to export my data?</p>