Schmersion is a little library to help generate CHANGELOG documents automatically from commits with messages that are formatted following the Conventional Commits style (generally that means they contain a type followed by a message).

Schmersion will take on a couple of roles for you:

• It will automatically generate/update a CHANGELOG document (formatted as markdown, yaml, whatever you want) in your repository and commit this to your repository.

• It will suggest the next version number following SemVer principles.

• It will create your version tag.

gem install schmersion

Start by entering the root of the repository for the app you wish to work with. Then run schmersion init to generate a .schmersion.yaml config file. Once created, open this up and configure it as appropriate with the types and export formats you want.

Next, run schmersion pending. This will tell you your current version (the latest version tag) and then tell you what your next version should be called and a list of valid commits that will be included in the CHANGELOG when released.

If you're happy with this, you can then run schmersion release which will take these commits, add them to your CHANGELOG files (as configured in .schmersion.yaml), commit them and make a tag with the given version number. There are a few options you can pass to the release method.

• --dry-run - run the release and just output what will happen to the terminal without actually running anything

• -r - override the next version number with a value of your choosing

• --pre [type] - specify that the next version should be a pre-release version. You can pass the prefix for this such as beta or rc and the commit will be suffixed with something like -beta.1 as appropriate.

• --skip-(export|commit|tag) - you can use this to skip individual steps of the release process as needed.

Schmersion can help make sure you write the correct commit messages too. To enable this, you need to run schmersion setup-linting each time your clone your repository. This will install some git commit hooks (prepare-commit-msg and commit-msg) that will validate your commit message comply with the requirements for the repository specified in the config file.

• schmersion versions - displays a list of all versions in date order.

• schmersion log - display all valid commits that are eligible for inclusion in version calculations and CHANGELOG exports.

• schmersion help - displays a list of available commands.

This is an example configuration file which should be placed in the root of the repository and named .schmersion.yaml.

# Types is a list of the commit types that are supported. This will be enforced by the
# linter when new commits are added. Commits that are added with a type not in this list
# will always be ignored by Schmersion (along with merge commits and commits which do not
# match the required format).
types:
  - feat
  - fix
  - chore
  - refactor

# If you wish to limit which scopes are valid, you can list them here. They apply to
# all types. Do not specify this if you wish to allow any scope.
scopes:
  - rspec
  - login

# These options allow you to configure the rules used for linting commit messages.
linting:
  max_description_length: 100

# These options allow you to customise how the next version is determined.
version_options:
  # By default, any breaking change will cause an increase to the MAJOR part of
  # of the version. You can disable this if you wish by setting this option to true.
  breaking_change_not_major: false

# Finally, you can define options for how you wish your CHANGELOG files to be
# exported when releases happen. You can define the name (path) where the file
# will be exported to as well as the formatter and any options which the formatter
# may wish to use. You can define as many exports as you wish.
exports:
  - name: CHANGELOG.md
    formatter: markdown
    options:
      # The title to add at the top of the file
      title: Katapult CHANGELOG
      # Some additional descriptive text
      description: Some example text which will be inserted at the top of the CHANGELOG.
      # URLs are used in some generated markdown files to link to various things.
      # By default, these are determined from the repository URL but you can override
      # these below if you wish.
      urls:
        commit: https://customdomain.com/$REF
      # An array of sections to include with a title and an array of commit types to
      # include in that section. Sections with no commits will be excluded.
      sections:
        - title: New Features
          types: [feat]
        - title: Bug Fixes
          types: [fix]

  - name: CHANGELOG.yaml
    formatter: yaml
    options:
      # The commit types to include the generated YAML file.
      types: [feat, fix]