Overview

When attempting to push Docker images to Google Container Registry (GCR), users may encounter permission errors despite having previously authenticated successfully. This guide outlines the necessary steps to ensure proper configuration and troubleshoot common issues.

Prerequisites

Before pushing images, ensure you have completed the following steps:

  1. Authenticate with Google Cloud: Run the following command to log in:

    gcloud auth login

  2. Configure Docker to use gcloud as a credential helper: Execute:

    gcloud auth configure-docker

  3. Set your active project:

    gcloud config set project gcp-project-id-example

  4. Install the necessary components:

    gcloud components install docker-credential-gcr

Pushing Docker Images

To push your Docker image, use the following command:

sudo gcloud docker -- push eu.gcr.io/gcp-project-id-example/pipelinebuild:latest

Note: The gcloud docker command is deprecated for Docker client versions above 18.03. Instead, use the standard Docker commands after configuring Docker with gcloud auth configure-docker.

Example of Using Docker Directly

After configuring, you can push images like this:

docker push eu.gcr.io/gcp-project-id-example/pipelinebuild:latest

Common Errors

If you encounter the following error:

denied: Token exchange failed for project 'gcp-project-id-example'. Caller does not have permission 'storage.buckets.get'.

This indicates that your user account lacks the necessary permissions to access the storage bucket associated with your GCR. To resolve this:

  1. Verify that your account has the appropriate roles assigned, such as Storage Admin or Editor.
  2. Follow the instructions in the GCR access control documentation to configure permissions correctly.

Alternative Authentication Method

If you prefer using a service account for authentication, you can log in using the following command:

docker login -u _json_key --password-stdin https://eu.gcr.io < aysc.json

Warning: This method will store your password unencrypted in the Docker configuration file. Consider configuring a credential helper to avoid this warning. For more details, refer to the Docker documentation.

Conclusion

If you continue to experience issues after following these steps, consider creating a new GCP project to rule out project-specific configurations. Always ensure your permissions are correctly set to avoid access-related errors.