Automate docker image Semantic Versioning with commit messages.

Given a docker IMAGE_TAGS_URL, docker-semver will find the current patch semantic version, then increment the version based on the provided GIT_COMMIT_MSG

A docker repository has the following tags:

• 2.2.1, 2.2, 2, latest
• 1.7.10, 1.7, 1

A commit is pushed with the message: "MINOR: new functionality X"

The following tags will be returned by docker-semver

• MAJOR: 2
• MINOR: 2.3
• PATCH: 2.3.0

docker-semver reads the first word in the commit message. It is case-insensitive.

• MAJOR: incompatible API changes
• minor: add functionality in a backwards compatible manner
• patch some fixes <-- colon is optional
• some commit message <-- increments a patch version by default

• If no semantic versions are found, docker-semver will return the tags:

  • 1
  • 1.0
  • 1.0.1

• By default, docker-semver will fetch up to 100 tags from the IMAGE_TAGS_URL. Set IMAGE_TAGS_LIMIT to override this.

docker run \
    -e IMAGE_TAGS_URL='https://hub.docker.com/v2/repositories/wexel/docker-semver/tags' \
    -e GIT_COMMIT_MSG='some commit message' \
    wexel/docker-semver \
    docker-semver

// Output
1
1.0
1.0.2

TAGS=$(docker run \
    -e IMAGE_TAGS_URL='https://hub.docker.com/v2/repositories/wexel/docker-semver/tags' \
    -e GIT_COMMIT_MSG='some commit message' \
    wexel/docker-semver \
    docker-semver)
[ $(echo "$TAGS" | wc -w) != "3" ] && exit 1

for tag in $TAGS; do
    [ -z "$MAJOR_TAG" ] && export MAJOR_TAG="$tag" && continue
    [ -z "$MINOR_TAG" ] && export MINOR_TAG="$tag" && continue
    [ -z "$PATCH_TAG" ] && export PATCH_TAG="$tag" && break
done

echo $MAJOR_TAG // 1
echo $MINOR_TAG // 1.0
echo $PATCH_TAG // 1.0.2