ASReview started from Docker Container is not able to talk to backend.

[Samy Ateia]

Describe the bug
When starting the docker container as described on the https://github.com/asreview/asreview/tree/master/Docker documentation,
The ASReview Frontend is not able to access the backend service.

The documentation states "If you are creating a Docker container that runs the app with a config file, do not forget to override the IP-address of the Flask backend. Set the HOST variable to "0.0.0.0" since the default "localhost" can't be reached from outside the container."
I suspect that is the problem but it is not documented where the default config file that is used when following the documentation is located or how one could add such a config file to the docker build.

To Reproduce

1. Follow the steps in the "building the simple version" section: https://github.com/asreview/asreview/tree/master/Docker#building-the-simple-version
2. Try to access ASreview on your local machine: http://localhost:8080/
3. Look that the errors thrown on the web console.

Version information

• OS: Windows
• ASReview version 1.3

[Samy Ateia]

Recent hotfix #1570 seems to have fixed the issue.