The simple stuff would be utilizing the following variables.
SOURCE_BRANCH: the name of the branch or the tag that is currently being tested.
SOURCE_COMMIT: the SHA1 hash of the commit being tested.
COMMIT_MSG: the message from the commit being tested and built.
DOCKER_REPO: the name of the Docker repository being built.
DOCKERFILE_PATH: the dockerfile currently being built.
DOCKER_TAG: the Docker repository tag being built.
IMAGE_NAME: the name and tag of the Docker repository being built. (This variable is a combination of DOCKER_REPO:DOCKER_TAG.)
If you wanted to take it up a notch, then Custom build phase hooks could provide arbitrary ARGS/--build-args
The simple stuff would be utilizing the following variables.
If you wanted to take it up a notch, then Custom build phase hooks could provide arbitrary
ARGS
/--build-args