Container

Extension can run actions in a Docker container when container is specified on an extension block:

extension @terraform {
    container = "hashicorp/terraform:1.8.4"
    platform = "linux/arm64"
    variables = [ "ARM_*"
                  "MYSECRET" ]
}

Argument Reference

The following arguments are supported:

• container - (Optional) The Docker image to use. Default is nothing.
• platform - (Optional) The platform for the Docker image. Default is nothing (i.e.: current host architecture).
• variables - (Optional) List of variables to pass to Docker instance. Supports wildcards. Default is [].

All actions for this extension will run in the configured container - hence providing both isolation and avoiding toolchains discrepancies.

Technical implementation

All actions are run using following docker configuration:

• Entrypoint and arguments are overriden by action (--entrypoint)
• Container is removed after execution (--rm)
• Container uses provided platform - use default if none
• Docker host socket is exposed to container to allow Docker in Docker (-v /var/run/docker.sock)
• Container USER account is identified and used to map host homedir to USER homedir (-v)
• Container /tmp is redirected and shared across instances (v)
• Container workdir is the current project rootdir (-w)
• Network is set to host (--net=host)
• IPC is set to host (--ipc=host)
• PID is set to host (--pid=host)
• Environment variables can be passed from host to container - see variables property of extensions.