Syncing your project

Syncing is supposed to integrate any changes to the mlf-core templates back into your already existing project. When mlf-core sync is invoked, mlf-core checks whether a new version of the corresponding template for the current project is available. If so, mlf-core creates a temporary project with the most recent template and pushes it to the TEMPLATE branch. Next, a temporary sync branch is created to avoid pushing and manipulating the TEMPLATE branch (called mlf_core_sync_v_<<new-version>> with new-version being the updated templates version). Finally, a pull request is submitted to the development branch from this branch.

The syncing process is configurable by setting the desired lower syncing boundary level and blacklisting files from syncing (see Enable/Disable sync).

Requirements for sync

For syncing to work properly, your project has to satisfy a few things:

  1. A Github repository with your projects code (private or public, organization or non-organization repository).

  2. An unmodified .mlf_core.yml file. If you modify this file, which you should never do, syncing may not be able to recreate the project with the most recent template.

  3. An active repository secret called CT_SYNC_TOKEN for your project’s repository containing the encrypted personal access token with at least repo scope.

  4. A running, unmodified workflow called sync_project.yml. Modifying this workflow should never be done and results in undefined sync behaviour.

Points 3 and 4 are only required when not syncing manually.


To sync your project manually, simply run

  • PROJECT_DIR [CWD] : The path to the mlf_core.cfg file.

  • PAT [Configured pat] : A Github personal access token with at least the repo scope. The sync_project.yml Github workflow uses the PAT set as a Github secret.

  • GITHUB_USERNAME [Configured username] : The Github username to submit a pull request from. The supplied PAT has to be associated with this username.


  • --set-token : Update CT_SYNC_SECRET of your project’s repo to a new PAT. Note that the Github username and the PAT must still match for automatic syncing to work.

  • check-update : Check, whether a new release of a template for an already existing project is available.

Configuring sync

Enable/Disable sync

Mlf-core aims to provide the user as much configuration as possible. So, the sync feature is optional and should also be switched on or off. If you want to enable sync (which is the default), the sync_enable accepts the following values: True, true, Yes, yes, Y, y. To disable sync, simply change this value into False, false, No, no, N, n. It can be configured in the:

sync_enabled = True


Sync level

Since mlf-core strongly adheres to semantic versioning our templates do too. Hence, it is customizable whether only major, minor or all (= patch level) releases of the template should trigger mlf-core sync. The sync level therefore specifies a lower boundary. It can be configured in the:

ct_sync_level = minor


Blacklisting files

Although, mlf-core only submits pull requests for files, which are part of the template, sometimes even those files should be ignored. Examples could be any html files, which ,at some point, contain only custom content and should not be synced. When syncing, mlf-core examines the mlf_core.cfg file and ignores any file patterns (globs) (e.g. *.html) below the [sync_files_blacklisted] section. IMPORTANT NOTE: If you would like to add some files to this section, make sure your current branch (if you are syncing manually, which is not recommended) or your default branch has the latest blacklisted sync file section with your changes, so it will be used by the sync.