Supported builder engines

Contents

• Supported builder engines
  • Docker builder
    • Docker environment variables
  • OSBS builder
  • Buildah builder
  • Podman builder

CEKit supports following builder engines:

• Docker builder – builds the container image using Docker
• OSBS builder – builds the container image using OSBS service
• Buildah builder – builds the container image using Buildah
• Podman builder – builds the container image using Podman

Docker builder

This builder uses Docker daemon as the build engine. Interaction with Docker daemon is done via Python binding.

Input format

Dockerfile

Parameters

--pull

Ask a builder engine to check and fetch latest base image

--tag

An image tag used to build image (can be specified multiple times)

--no-squash

Do not squash the image after build is done.

Example

Building Docker image

$ cekit build docker

Docker environment variables

It is possible to use environment variables to let CEKit know where is the Docker daemon located it should connect to.

Note

Read more about Docker daemon settings related to exposing it to clients.

By default, if you do not specify anything, CEKit will try to use a locally running Docker daemon.

If you need to customize this behavior (for example when you want to use Docker daemon running in a VM) you can set following environment variables:

DOCKER_HOST

The DOCKER_HOST environment variable is where you specify where the Daemon is running. It supports multiple protocols, but the most widely used ones are: unix:// (where you specify path to a local socket) and tcp:// (where you can define host location and port).

Examples of DOCKER_HOST: unix:///var/run/docker.sock, tcp://192.168.22.33:1234.

Depending how your daemon is configured you may need to configure settings related to encryption.

# Connect to a remote Docker daemon
$ DOCKER_HOST="tcp://192.168.22.33:1234" cekit build docker

DOCKER_TLS_VERIFY

You can set DOCKER_TLS_VERIFY to a non-empty value to indicate that the TLS verification should take place. By default certificate verification is disabled.

DOCKER_CERT_PATH

You can point DOCKER_CERT_PATH environment variable to a directory containing certificates to use when connecting to the Docker daemon.

OSBS builder

This build engine is using rhpkg or fedpkg tool to build the image using OSBS service. By default it performs scratch build. If you need a proper build you need to specify --release parameter.

Input format

Dockerfile

Parameters

--release

Perform an OSBS release build

--tech-preview

Build tech preview image, see below for more information

--user

Alternative user passed to build task

--nowait

Do not wait for the task to finish

--stage

Use stage environment

--koji-target

Overrides the default koji target

--commit-message

Custom commit message for dist-git

--sync-only

Generate files and sync with dist-git, but do not execute build

--assume-yes

Run build in non-interactive mode answering all questions with ‘Yes’, useful for automation purposes

Example

Performing scratch build

$ cekit build osbs

Performing release build

$ cekit build osbs --release

Buildah builder

This build engine is using Buildah.

Note

If you need to use any non default registry, please update /etc/containers/registry.conf file.

Input format

Dockerfile

Parameters

--pull

Ask a builder engine to check and fetch latest base image

--tag

An image tag used to build image (can be specified multiple times)

Example

Build image using Buildah

$ cekit build buildah

Build image using Buildah and tag it as example/image:1.0

$ cekit build buildah --tag example/image:1.0

Podman builder

This build engine is using Podman. Podman will perform non-privileged builds so no special configuration is required.

Input format

Dockerfile

Parameters

--pull

Ask a builder engine to check and fetch latest base image

--tag

An image tag used to build image (can be specified multiple times)

Example

Build image using Podman

$ cekit build podman

Build image using Podman

$ cekit build podman --pull