Otter Cascading

A GitHub App to execute cascading between the repository branches.

How to install

The Otter Cascading application can be installed in your organization via this link.

The application will need the following permissions to work:

• Read access to checks and metadata
• Read and write access to code and pull requests

How it works

What it does

The application will look for branches matching the pattern defined in the cascadingBranchesPattern option.
Then it will sort the branches and, based on the current branch you gave as input, will figure out if the cascading is needed and on which branch.
If the current branch is the defaultBranch given as configuration OR if the current branch is the last one matching the pattern, the plugin will do nothing.

If the plugin finds a branch candidate for cascading, it will try to create a Pull Request.

Plugged hooks

The application is plugged to 3 Github webhooks:

• push: Checks if one of the branches that requires cascading is updated.
• pull_request.complete: When a cascading pull request is merged, checks if a new evaluation of the pull request origin branch is required.
• check_suite: In case the bypassReviewers option is activated, when a check suite is completed (or stale) the application will merge the cascading pull request.

Configuration

The Otter Cascading application can be configured via a JSON file following the provided JSON schema in one of these possible files:

• .github/cascadingrc.json
• .github/.cascadingrc.json
• cascadingrc.json
• .cascadingrc.json

Example:

// .github/.cascadingrc.json file
{
  "$schema": "https://raw.githubusercontent.com/AmadeusITGroup/otter/main/apps/github-cascading-app/schemas/config.schema.json",
  "defaultBranch": "master",
  "ignoredPatterns": []
}

List of configurations

The following configurations are available:

Note: The bypassReviewers option will require to set the otter-cascading bot as bypass user to be able to merge the cascading/* pull requests.