Photo by Daniel McCullough on Unsplash

Introduction

This post takes place in a series aiming to show how to build an Angular application from scratch.

We will see how to scaffold an enterprise-scale angular application with all the assets needed to easily develop and maintain it.

This post will show you how to add support for conventional changelog generation for your application on Gitlab and add it to your CI tool chain.

Our goal will be to automate changelog generation on the master branch and generate a tag with the changelog updated :

• [Manual] Merge develop to master (by Pull Request).
• [Manual] Tag master with prerelease-X.Y.Z (on Gitlab or with git cli).
• [Automatic] CI triggered to update CHANGELOG.md and package.json + remove prerelease-X.Y.Z tag.
• [Automatic] Push to master and add tag X.Y.Z, release ready.

Git Workflow

git checkout develop
git pull
# Retrieve the last develop version

git checkout -b feature/changelog
# Feature Branch creation 

Make your repository Comitizen friendly

First, install the Commitizen cli tools:

npm install commitizen --save --save-exact --save-dev 

Next, initialize your project to use the cz-conventional-changelog adapter by typing:

commitizen init cz-conventional-changelog --save-dev --save-exact

The above command does three things for you.

• Installs the cz-conventional-changelog adapter npm module.
• Saves it to package.json's dependencies or devDependencies.
• Adds the config.commitizen key to the root of your package.json as shown here:

...
    "devDependencies": {
        ....
        "cz-conventional-changelog": "^3.1.0",
    }
...
    "config": {
        "commitizen": {
            "path": "./node_modules/cz-conventional-changelog"
        }
    }
... 

This just tells Commitizen which adapter we actually want our contributors to use when they try to commit to this repo.

Use Comitizen

Add comitizen script to your package.json.

    "scripts": {
        ...
        "commit": "git-cz"
        ...
    },

Use npm run commit instead of git commit to enjoy!

When you're working in a Commitizen friendly repository, you'll be prompted to fill in any required fields and your commit messages will be formatted according to the standards you defined above.

Use Conventional Changelog

Install the Conventional Changelog CLI :

npm install conventional-changelog-cli --save --save-exact --save-dev 

Update your package.json to include the followings script :

"scripts": {
    ...
    "init-changelog": "conventional-changelog -p angular -i CHANGELOG.md -s -r 0",
    "version": "conventional-changelog -p angular -i CHANGELOG.md -s && git add CHANGELOG.md"
    ...
}

Initialise the Changelog :

npm run init-changelog

Update your Node configuration

With the new npm script version, we will add some logic to the npm versionlife-cyle. The .npmrc file helps us to define some variables used when npm version is called.

Update your .npmrc file or create one with :

tag-version-prefix=""
message="chore(release): Version %s"

For more informations about the npm versionlife-cycle, refer to :
https://docs.npmjs.com/cli/version

Update your CI

Generate your GitLab access token

Go to your Gitlab, User Settings > Access Token and create a new token named GIT_ACCESS_TOKEN with the api scope checked.
Your new personal access token will be prompt, save it :

Now, go to your project Settings > CI/CD panel

Expand the Variable panel and click on Add Variable.

Name the variable GIT_ACCESS_TOKEN and past the personal access token saved from before, make sure protected and masked are unchecked.

The variable $GIT_ACCESS_TOKEN can now be accessed from your CI jobs and enable credential to write/read your git repository.

Update your CI jobs

Update your .gitlab-ci.yml to add a publish-version step.
This step will be triggered when tagging your code with prerelease-X.Y.Z tags (ie. prerelease-1.0.0).

It will :

• Retrieve the current prerelease-X.Y.Z tag.
• Update your application version (in package.json, package-lock.json and npm-shrinkwrap.json) to the X.Y.Z value.
• Run the npm version command and commit and tag in git.
• Under the hood, run the version script defined above to update the CHANGELOG.md and add it to the commit.
• Remove the prerelease-X.Y.Z tag from your repository.
• Add the updated file to git and push the modifications to the master branch and tag it as X.Y.Z.

image: node:latest

stages:
  - CodeQuality
  - Release

test:
  stage: CodeQuality
  script: 
    - npm ci
    - npm run ci:test

lint:
  stage: CodeQuality
  script:
    - npm ci
    - npm run ci:lint

publish-version:
  image: node:12.16.1
  stage: Release
  rules:
     - if: '$CI_COMMIT_TAG =~ /^prerelease-\d+.\d+.\d+/'
  before_script:
    - npm ci
    - npm config set unsafe-perm true
  script:
    - TAG_VERSION=`echo $CI_COMMIT_TAG | sed "s/.*prerelease-\([^ ]*\).*/\1/"`
    - git config --global user.name "$GITLAB_USER_NAME"
    - git config --global user.email "$GITLAB_USER_EMAIL"
    - git remote set-url origin "https://gitlab-ci-token:$GIT_ACCESS_TOKEN@$CI_SERVER_HOST/$CI_PROJECT_PATH.git"
    - git tag -d $CI_COMMIT_TAG
    - git push origin --delete $CI_COMMIT_TAG
    - npm version $TAG_VERSION
    - git push origin HEAD:master --tags

Push your modifications.

git add package.json package-lock.json .gitlab-ci.yml CHANGELOG.md .npmrc

# Use the magic !!
npm run commit

git push -u origin feature/changelog

Each time you tag your master branch with a tag prerelease-X.Y.Z, the CI will take care of updating your application version and generating the corresponding Changelog.