github-helpers

A collection of Github Actions that simplify and standardize common CI/CD workflow tasks.

Usage

General

uses: ExpediaGroup/github-helpers@v1
with:
    helper: <HELPER NAME>

The helper input is required for all helpers, and the github_token input defaults to the included workflow token ${{ github.token }}. Additional inputs vary by helper. Each helper file in src/helpers contains an interface that defines which additional inputs are required or optional. If a required input is ommitted, the helper will throw a descriptive error.

Example

Input interface in src/helpers/set-commit-status.ts:

export class SetCommitStatus {
    sha = ''; // required
    context = ''; // required
    state = ''; // required
    description?: string; // optional
    target_url?: string; // optional
}

Github Actions workflow invocation:

uses: ExpediaGroup/github-helpers@v1
with:
    helper: set-commit-status
    sha: ${{ github.event.pull_request.head.sha }}
    context: My Context
    state: success
    description: My Description

Available Helpers

Each of the following helpers are defined in a file of the same name in src/helpers:

are-reviewers-required

• Returns true if all teams specified are requested for review on a pull request

add-labels

• Adds one or more labels to a PR

add-late-review-label

• Adds a LATE REVIEW label to all PRs that are open and waiting for review for over a certain number of days

add-pr-approval-label

• Upon PR review, adds a CORE APPROVED label if the reviewer is a part of the provided Github team, otherwise adds the PEER APPROVED label

approvals-satisfied

• Returns true if the PR has been approved by the specified GitHub team(s) and false otherwise
• If GitHub teams are omitted, uses CODEOWNERS.md to determine teams to use

approve-pr

• Approves a PR

assign-pr-reviewers

• Randomly assigns members of the specified GitHub team(s) to review a PR.
• If GitHub teams are omitted, uses CODEOWNERS.md to determine teams to use
• If login is provided, it does nothing if that user is already part of the team
• You can also pass a slack_webhook_url to notify the assignees that they are assigned to the PR!

check-merge-safety

• Checks if a PR branch needs to update with the default branch prior to merging (great for monorepos!)
• If this check succeeds for a PR, the PR is safe to merge right away!
• If this check fails for a PR, the PR must either merge in the default branch or rebase onto the default branch.

"Merge safety" is defined as a PR's branch being up to date with all files that could impact the validity of the PR checks that run. This merge safety check is designed to be a smarter alternative to GitHub's "require branches to be up to date before merging" branch protection rule.

The below table (taken from the above link) outlines the current branch protection rule settings GitHub provides:

Type of required status check	Setting	Merge requirements	Considerations
Strict	The Require branches to be up to date before merging checkbox is checked.	The branch must be up to date with the base branch before merging.	This is the default behavior for required status checks. More builds may be required, as you'll need to bring the head branch up to date after other collaborators merge pull requests to the protected base branch.
Loose	The Require branches to be up to date before merging checkbox is not checked.	The branch does not have to be up to date with the base branch before merging.	You'll have fewer required builds, as you won't need to bring the head branch up to date after other collaborators merge pull requests. Status checks may fail after you merge your branch if there are incompatible changes with the base branch.

The "Strict" option is too strict! It opens the door to needless additional PR check runs when a PR is updated with commits that changes files completely unrelated to the scope of the PR's change.

The "Loose" option is too loose! There are times when a commit is made to the default branch that renders PR checks stale (specifically when files are changed that could impact the result of builds or tests).

The check-merge-safety helper offers a middle-ground between the "Strict" and "Loose" options, giving us the best of both worlds! Using this helper allows us to uncheck the "Require branches to be up to date before merging" checkbox while forcing PRs to incorporate the latest relevant changes into the CI process. This way, we can ensure that only the necessary iterations of PR check runs occur, allowing contributors touching unrelated parts of the codebase to ship code in quick succession!

This workflow should be run on both pull_request and push events:

• On pull_request events, this serves as a PR check
• On push events, this effectively re-runs this PR check for all open PRs and sets a commit status according to the result

The following parameters can be used for additional control over when it is safe to merge a PR:

• paths: These are the file paths to all of a repo's projects (usually paths to standalone packages)
  • This is useful for monorepos with multiple projects which are decoupled from each other but are affected by global dependencies.
• ignore_globs: These are glob patterns that, if out of date on a PR, will not prevent merge
  • example: ignore_globs: **.md
• override_filter_paths: These are the file paths that, if out of date on a PR, will prevent merge no matter what files the PR is changing
  • example: override_filter_paths: package.json,package-lock.json
• override_filter_globs: These are glob patterns for override_filter_paths

close-pr

• Closes a pull request

create-pr

• Opens a pull request

create-project-card

• Creates a Project card into your GitHub Project repository by providing a project_name and project_destination_column_name in which the card should be created.
• If note is provided, it will add that information into the card. If it is not provided, it will use the PR information details to populate it.
• Useful when opening a pull request and want to track its information details into a GitHub Project.

check-pr-title

• Checks whether PR title matches a certain regular expression

create-pr-comment

• Comments on a pull request or other issue

delete-stale-branches

• Deletes all of a repository's unprotected branches not associated with an open PR and which have been inactive for a certain number of days

delete-deployment

• Deletes a Github deployment and environment

filter-paths

• Returns true if specified file paths have changed for a PR, and false otherwise

generate-matrix

• Returns a job matrix JSON for dynamically running workflows

generate-path-matrix

• Returns a job matrix JSON for dynamically running workflows only for changed file paths
• Can be used to parallelize similar jobs, which can be useful in a monorepo environment. More information on matrix strategies can be found here
• In this example, a multi-package repo splits its builds dynamically based on which packages are modified in the pull request. These builds run in parallel, and the final build-status job is used to determine the overall success/failure result, contingent on all of the individual build jobs passing. The helper returns a JSON object of this format:

{
    "include": [{ "path": "package-name" }]
}

Additionally, the following parameters can be used for additional control over the resulting matrix:

• override_filter_paths defines paths that, if modified, will override the filter and return a matrix including all packages
  • example: override_filter_paths: package.json,package-lock.json
• paths_no_filter defines paths that should be included in the matrix regardless of if they've been modified
• batches defines a fixed number of matrix jobs to run for the workflow

get-changed-files

• Returns a comma-separated list of changed files for a PR
• Include the regular expression parameter 'pattern' to add a filter, it will return any filepath that matches.

initiate-deployment

• Creates a new in-progress Github "deployment" for a commit. More information on Github deployment events can be found here

is-user-in-team

• Checks if the specifed GitHub user exists within an organization team

manage-issue-due-dates

• Adds a comment listing the due date (based on SLA guidelines) to issues with a priority label attached
• Adds a 'due soon' label to issues with a priority label that will become overdue in 7 days
• Adds an 'overdue' label to issues with a priority label that are overdue

manage-merge-queue

• Manages a queue for PRs as follows:
  • Adding the READY TO MERGE label to a PR will add the PR to the "merge queue", represented by a QUEUED FOR MERGE #X label. Removing READY TO MERGE will remove this label and thus remove the PR from the queue.
  • If a PR is first in the queue, the QUEUE CHECKER commit status will be set to success, and it will be pending otherwise. Github's branch protection rules can be used to ensure this requirement is met prior to merging.
  • Merging a PR will update the positions of all PRs in the queue.
  • Adding the JUMP THE QUEUE label to a PR will make that PR first in the queue immediately.
  • When a PR is merged, it automatically updates the first-queued PR with the default branch.
• You can also pass login and slack_webhook_url to notify the PR author when they are in the 1st position of the merge queue.

move-project-card

• Moves a GitHub Project card to a new column, using the project_origin_column_name andproject_destination_column_name you provide.
• In order to move a card from one place to another, it must already exist.

notify-pipeline-complete

• Sets a "pipeline" commit status to green for all open PRs

prepare-queued-pr-for-merge

• Merges the default branch into the pull request that has the QUEUED FOR MERGE #1 label

remove-label

• Removes a label from a PR

remove-pr-from-merge-queue

• Removes a PR from the merge queue if it has a stale failing status check. A PR check is considered stale if it is older than the provided number of seconds.

rerun-pr-checks

• Reruns all of the latest workflow checks on a pull request (helpful if they were cancelled for some reason, either manually or due to rate limiting, for example).

set-commit-status

• Sets a commit status
• You can pass in skip_if_already_set: true if you'd like to skip setting a status if it's already been set on the commit by a workflow

set-deployment-status

• Updates a Github deployment status

set-latest-pipeline-status

• Determines whether the pipeline is clear for a PR. This means it will set the "pipeline" commit status to pending if there is an in-progress production deployment for the repo, and success otherwise.

Legal

This project is available under the Apache 2.0 License.

Copyright 2021 Expedia, Inc.