Importing project into gitlab.com takes forever and or fails with no such file or directory

Summary

Trying to move projects from a selfhosted gitlab installation to gitlab.com. import fails or times out.

Steps to reproduce

1. Create a docker installation of gitlab (mine was 9.2.5-ce.0, but I tried with gitlab-ce:latest too), create a project, add an issue, add a readme, go to settings and hit export.
2. go to gitlab.com, create a new project and import from gitlab export button.

Wait for 54000 seconds

It will fail with

Import timed out. Import took longer than 54000 seconds

or something like this:

Error importing repository  into some_group/some_project - tar (child): [REPO EXPORT PATH]/uploads/a7a1e1e3f1bdfe5f918d2afb4dd4d41a_some_project: Cannot open: No such file or directory
tar (child): Error is not recoverable: exiting now
tar: Child returned status 2
tar: Error is not recoverable: exiting now
, undefined method `join' for nil:NilClass
Did you mean?  JSON

You can give a try with the following import-testing exported file: 2017-09-18_18-29-223_GabLeRoux_import-testing_export.tar.gz

I've sent it here: https://gitlab.com/gableroux/testing-import/import And it's taking quite some time for such an empty project ;)

What is the current bug behavior?

I can't import projects from this import feature and I really want this as I want to bring in issues.

What is the expected correct behavior?

Project should be imported with issues, wiki, deployment key, etc.

Relevant logs and/or screenshots

Output of checks

This bug happens on GitLab.com

Possible fixes

Selfhosting :( but for some reason, when I try to go to the import page, it gives me 404 on my local docker-compose installation so I can't even reproduce locally, I don't reach it, but that's probably an other issue. Import Works in a local gitlab installation.