Include: - project: computing/gitlab-ci-templates file: python/lint.yml - project: computing/gitlab-ci-templates file: workflow/sccb.yml - project: computing/gitlab-ci-templates file: cluster/ssh.yml: variables: # Allow Celery to run as root, because everything runs as root under Docker. CFORCEROOT: ' true ' # Checking out the source is the exception rather than the rule because. Use Docker to build Docker images. You can use GitLab CI/CD with Docker to create Docker images. For example, you can create a Docker image of your application, test it, and publish it to a container registry. To run Docker commands in your CI/CD jobs, you must configure GitLab Runner to support docker commands. Use Docker to build Docker imagesall tiers. You can use GitLab CI/CD with Docker to create Docker images. For example, you can create a Docker image of your application, test it, and publish it to a container registry. To run Docker commands in your CI/CD jobs, you must configure GitLab Runner to support docker commands.

If you’re using GitLab CI to build your software, you might also want to use it to build Docker images of your application.This can be a little tricky, because by default GitLab CI runs jobs inside Docker containers. Avenir next rounded font family free download.

The standard technique for getting around this problem is using Docker-in-Docker, but you can also use a simpler technique by using Podman, the reimplemented version of Docker.Let’s see why and how.

Option #1: Docker-in-Docker

When you run the docker command-line tool, it is actually not doing much work itself.Instead, it talks to dockerd, a daemon or server typically running on the same machine where you’re running the CLI.The actual work of running a container or building an image is done by dockerd.

When you want to run docker inside GitLab CI, you face the issue that GitLab CI jobs typically run as Docker containers.So you can’t just rely on a normal dockerd being available as you would, for example, in a virtual machine.

To help with this scenario, there’s a Docker image that runs dockerd for you: docker:dind.Once that is running, you can point docker at that running daemon and issue commands like docker build.

.gitlab-ci.yml Docker Python

In the context of GitLab CI, your jobs can run services, which are also Docker containers.So we can configure .gitlab-ci.yml to run docker:dind as a service in a job:

In this case, the service is given the hostname alias dockerdaemon.You also need to tell the docker CLI how to find the server, which you can do via an environment variable DOCKER_HOST, as well as set a couple of other variables that make it work, and work faster:

A full configuration that builds an image and pushes it to the GitLab image registry corresponding to the GitLab CI repository looks like this:

Gitlab Ci Python Docker Example

For more details see the relevant GitLab CI documentation.

A working example

I’ve set up an example repository that contains this configuration.Here’s what the Dockerfile looks like:

Like most GitLab repositories, it has a corresponding Docker image registry, and you can run the image built by the above configuration like so:

Note: Outside the very specific topic under discussion, the Dockerfiles in this article are not examples of best practices, since the added complexity would obscure the main point of the article.

To ensure you’re following all the best practices you need to have a secure, correct, fast Dockerfiles, check out the Python on Docker Production Handbook.

Gitlab Ci Python Docker

Option #2: Podman

Podman is a reimplemented version of Docker from RedHat.It supports the same command-line options, but has a fundamentally different architecture: unlike Docker, there is no daemon by default.The CLI does all the work itself.

That means we can do a much simpler GitLab CI config, without the service running the daemon:

Notice all we had to do was change the docker command-line to do podman instead; they basically accept the same options.

A working example

The same example repository is also configured to use Podman.Again, you can run the resulting image:

Docker-in-Docker (DinD) vs Podman

Which of these two should you choose?DinD gives you access to BuildKit, which has some useful features and performance improvements; Podman does not support all of them yet, though it does support build secrets.

On the other hand, running the DinD daemon adds some overhead, since another image has to be downloaded; the DinD build adds another 20 seconds of fixed overhead in my test.For less trivial builds this overhead probably will be overwhelmed by other factors.

Citra shared font file. If you don’t care about BuildKit’s additional features, using Podman is just a little bit simpler while offering the same user experience.Finally, you could look into Buildah, which is how podman build is implemented: it’s a tool specifically focused only on building images.