Docker registry push hangs with dash in image name

Summary

I tried to push an image with a dash in its name, but the push never completed.

Steps to reproduce

  • docker pull alpine:3.6
  • docker tag alpine:3.6 gitlab.example.com:1340/example/duck/go-backend:3.6
  • docker push gitlab.example.com:1340/example/duck/go-backend:3.6

What is the current bug behavior?

$ docker push gitlab.example.com:1340/example/duck/go-backend:3.6
The push refers to a repository [gitlab.example.com:1340/example/duck/go-backend]
5bef08742407: Pushing [==================================================>]  4.221MB

In this state it hangs, I waited 10 minutes but nothing works. Everything works well if I name the image gobackend instead of go-backend. I couldn't reproduce it with names containing dashes that were not go-backend.

What is the expected correct behavior?

The push doesn't hang but completes

GitLab Version

GitLab Community Edition 9.5.5