Container Plugin

The container.in plugin provides the config API to allow configuring the container backend.

Introduction

Clace can build and manage containers for implementing the app backend APIs. The config API is used to configure at the app level what configuration is used for the container.

API

The container.in plugin has just one main api, config

The config API supports the following parameter:

• src (string, optional) : the source for containerfile, auto by default
• port (int, optional) : the port number exposed from the container
• scheme (string, optional) : the url scheme, http by default
• health (string, optional) : the health check API, / by default
• lifetime (string, optional) : the lifetime for the container, default is to start a service when app is initialize. Set to container.COMMAND to allow running commands against the container using container.run without starting a service.
• build_dir (string, optional) : the build directory for the build, / by default

When the src is auto, the container file is auto detected. It checks for presence of either Containerfile or Dockerfile. If the value begins with image:, the subsequent portion is treated as the image to download. No image build is done in that case. Any other value for src is treated as the file name to use as the container file.

port can be specified in the container file, using a EXPOSE directive. If a value other than zero is specified in the config, that takes precedence over the value in the Expose.

The container plugin also supports the run API, same as the exec plugin. This allows running a command inside a container.

A sample program using the container config is

load("proxy.in", "proxy")
load("container.in", "container")

app = ace.app("My App",
              routes=[
                  ace.proxy("/", proxy.config(container.URL))
              ],
              container=container.config(container.AUTO),
              permissions=[
                  ace.permission("proxy.in", "config", [container.URL]),
                  ace.permission("container.in", "config", [container.AUTO])
              ]
       ) 

A app which runs an command against a specified image (see image-cmd spec is

load("container.in", "container")

def run(dry_run, args):
    split = args.command.split(" ")
    res = container.run(split[0], split[1:], parse_json=args.json).value
    return ace.result("Command output", res)

app = ace.app(param.app_name + " : " + param.image ,
    actions=[
       ace.action("Run Command using " + param.image, "/", run, description="Run specified command in container", hidden=["secrets", "app_name", "image"])
    ],
    container=container.config("image:" + param.image, lifetime=container.COMMAND),
    permissions=[
       ace.permission("container.in", "config", ["image:" + param.image], secrets=param.secrets),
       ace.permission("container.in", "run", secrets=param.secrets)
    ]
)