ACMS config

Basic Git repo initialized with demo content for the ACMS.

Breaking Change

The default branch has changed from master to main. If you rely on the previous default, pass the DEFAULT_BRANCH build argument when building the image:

docker build --build-arg DEFAULT_BRANCH=master -t artcom/acms-config .

The -e DEFAULT_BRANCH=master runtime override is only needed if the image was built without the correct build argument.

Usage

docker build -t artcom/acms-config .
docker run artcom/acms-config

Build Arguments

Argument	Default	Description
DEFAULT_BRANCH	main	Name of the Git branch created in the bare repository at build time.

docker build --build-arg DEFAULT_BRANCH=master -t artcom/acms-config .

Default Branch

The bare Git repository is initialized at build time with a branch named after the DEFAULT_BRANCH build argument (default: main).

At container startup, the entrypoint script 50-set-default-branch.sh reconciles the repository's branch name with the DEFAULT_BRANCH environment variable. If the names differ it renames the branch in-place (by moving the ref and updating HEAD) so that clients always see the configured name as the default branch, regardless of what was baked in at build time.

Configuration Change Hook

When a push is accepted into the bare Git repository, a post-receive hook publishes an MQTT event to <BASE_TOPIC>/onConfigurationChange.

The hook is installed globally via core.hooksPath during the Docker build — no per-repository symlink is needed.

Payload

One message is published per updated ref:

{
  "refName": "refs/heads/master",
  "changedFiles": [
    "config/content/pages/page001/index.json",
    "config/content/pages/page002/index.json"
  ]
}

Field	Type	Description
refName	string	Fully-qualified Git ref that was updated (e.g. refs/heads/master).
changedFiles	string[]	Paths of files that differ between the old and new commit, as returned by git diff --name-only.

Environment Variables

Variable	Default	Description
DEFAULT_BRANCH	main	Default Git branch name. Initialized at build time; reconciled at container startup if overridden at runtime.
TCP_BROKER_URI	""	MQTT broker URI (e.g. mqtt://10.0.0.1). Leave as "" (empty string) to disable the hook entirely.
BROKER_USERNAME	""	MQTT broker username. Leave as "" (empty string) to avoid setting broker auth credentials.
BROKER_PASSWORD	""	MQTT broker password. Leave as "" (empty string) to avoid setting broker auth credentials.
BASE_TOPIC	root	Base MQTT topic. The change event is published to <BASE_TOPIC>/onConfigurationChange.