func/docs/guides/podman.md

Podman

Under Linux, it is possible to use podman instead of docker. With Functions, you'll need podman version v3.3 or better for this to work properly.

In order to do this you need to run podman as a service. You can do this with the following command.

❯ systemctl start --user podman.socket

This will serve the Docker API on a UNIX socket at ${XDG_RUNTIME_DIR}/podman/podman.sock (on most systems that would be /run/user/{uid}/podman/podman.sock).

Then set the environment variable DOCKER_HOST to the socket so func knows where to connect.

❯ export DOCKER_HOST="unix://${XDG_RUNTIME_DIR}/podman/podman.sock"
❯ func build -v

Now you may use func as usual.

macOS

Under macOS you need to use podman machine as podman is native to Linux.

❯ brew install podman
❯ podman machine init --cpus=2 --disk-size=30 --memory=8192
❯ podman machine start
❯ ssh-add -k $HOME/.ssh/podman-machine-default
❯ export DOCKER_HOST=(podman system connection ls --format="{{.URI}}" | grep root)

Known issues

• In func version 0.19, some runtimes might be unable to build a function by using podman. You might see an error message similar to the following:

  ERROR: failed to image: error during connect: Get "http://%2Fvar%2Frun%2Fdocker.sock/v1.40/info": EOF
  

  • The following workaround exists for this issue:

    • Update the podman service by adding --time=0 to the service ExecStart definition in the podman configuration file at /etc/systemd/user/podman.service.You might need to copy the default configuration file from /usr/lib/systemd/user/podman.service first.
      
      Example service configuration:

      ExecStart=/usr/bin/podman $LOGGING system service --time=0
      
      After editing the configuration files you need to reload/restart service:

      ❯ systemctl --user daemon-reload
      ❯ systemctl restart --user podman.socket