Chapter 7. Building Dockerfiles

Red Hat Quay supports the ability to build Dockerfiles on our build fleet and push the resulting image to the repository.

7.1. Viewing and managing builds

Repository Builds can be viewed and managed by clicking the Builds tab in the Repository View.

7.2. Manually starting a build

To manually start a repository build, click the + icon in the top right of the header on any repository page and choose New Dockerfile Build. An uploaded Dockerfile, .tar.gz, or an HTTP URL to either can be used for the build.

Note

You will not be able to specify the Docker build context when manually starting a build.

7.3. Build Triggers

Repository builds can also be automatically triggered by events such as a push to an SCM (GitHub, BitBucket or GitLab) or via a call to a webhook.

7.3.1. Creating a new build trigger

To setup a build trigger, click the Create Build Trigger button on the Builds view page and follow the instructions of the dialog. You will need to grant Red Hat Quay access to your repositories in order to setup the trigger and your account requires admin access on the SCM repository.

7.3.2. Manually triggering a build trigger

To trigger a build trigger manually, click the icon next to the build trigger and choose Run Now.

7.3.3. Build Contexts

When building an image with Docker, a directory is specified to become the build context. This holds true for both manual builds and build triggers because the builds conducted by Red Hat Quay are no different from running docker build on your own machine.

Red Hat Quay build contexts are always the specified subdirectory from the build setup and fallback to the root of the build source if none is specified. When a build is triggered, Red Hat Quay build workers clone the git repository to the worker machine and enter the build context before conducting a build.

For builds based on tar archives, build workers extract the archive and enter the build context. For example:

example
├── .git
├── Dockerfile
├── file
└── subdir
    └── Dockerfile

Imagine the example above is the directory structure for a GitHub repository called "example". If no subdirectory is specified in the build trigger setup or while manually starting a build, the build will operate in the example directory.

If subdir is specified to be the subdirectory in the build trigger setup, only the Dockerfile within it is visible to the build. This means that you cannot use the ADD command in the Dockerfile to add file, because it is outside of the build context.

Unlike the Docker Hub, the Dockerfile is part of the build context on Red Hat Quay. Thus, it must not appear in the .dockerignore file.