gcloud docker sudden #FAIL

I had been happily pushing docker images to Google Container Registry via gcloud docker -- push for as long as I can remember. Then suddenly it started to fail with an error message exactly the same as this

gcloud docker -- push results in login attempt failed with 404

I went to Twitter and Slack to talk to other GCP experts, and I couldn’t find anybody with the exact same symptoms.

Then I realized this thing called docker-credential-gcr , which sounded interesting.

During the course of previous discussion with experts, one of them actually did mention this tool as well, so I gave it a go.

I wanted to use the gcloud default application settings, so I followed the documentation at this page:

GoogleCloudPlatform/docker-credential-gcr

And I did:

$ docker-credential-gcr configure-docker
$ docker-credential-gcr config --token-source="gcloud"

Then changed my script to use docker push instead of gcloud docker -- push and voila, it worked.

I have not idea what happened, but it worked. Oh well.