GitHub actions to trigger build on new Pull Requests - github

Question

I have the following workflow to trigger CMake builds on my GitHub project:
name: C/C++ CI
on:
push:
branches: [ master, develop ]
pull_request:
types: [ opened, edited, reopened, review_requested ]
branches: [ master, develop ]
jobs:
build:
runs-on: ubuntu-18.04
steps:
- name: Install deps
run: sudo apt-get update; sudo apt-get install python3-distutils libfastjson-dev libcurl4-gnutls-dev libssl-dev -y
- uses: actions/checkout#v2
- name: Run CMake
run: mkdir build; cd build; cmake .. -DCMAKE_INSTALL_PREFIX=/home/runner/work/access/build/ext_install;
- name: Run make
run: cd build; make -j8
I expected it to trigger builds on new Pull Requests and have the build status as a condition to approve the merging.
However I'm finding it a bit challenging to achieve such results. I'm sort of a newbie when it comes to GitHub Actions.

Answer 1

I'm able to accomplish your scenario with a combination of github actions and github protected branch settings.
You've got your github actions setup correctly to run on a Pull Request with a destination branch: master or develop.
Now you have to configure your repo to prevent merging a PR if the CI fails:
On your Github Repo, go to Settings => Branches => Add a rule => Set branch name pattern to master => Enable 'Require status checks to pass before merging' => Status checks found in the last week for this repository pick the CI build you want to enforce

Answer 2

Until I write this response there is no way to do that only using GitHub actions, but you can do that by writing an action, using javascript or other of languages supported by GitHub Actions.
import * as core from '#actions/core'
import * as github from '#actions/github'
import {getRequiredEnvironmentVariable} from "./utils";
type GitHubStatus = { context: string, description?: string, state: "error" | "failure" | "pending" | "success", target_url?: string }
function commitStatusFromConclusion(conclusion: CheckConclusion): GitHubStatus{
let status: GitHubStatus = {
context: "branch-guard",
description: "Checks are running...",
state: "pending",
};
if (conclusion.allCompleted) {
if (conclusion.failedCheck) {
status.state = "failure";
status.description = `${conclusion.failedCheck.appName} ${conclusion.failedCheck.conclusion}`;
status.target_url = conclusion.failedCheck.url
} else {
status.state = "success";
status.description = "All checks are passing!";
}
}
return status;
}
export async function setStatus(repositoryOwner: string, repositoryName: string, sha: string, status: GitHubStatus): Promise<number> {
let api = new github.GitHub(getRequiredEnvironmentVariable('GITHUB_TOKEN'));
let params = {
owner: repositoryOwner,
repo: repositoryName,
sha: sha,
};
let response = await api.repos.createStatus({...params, ...status});
return response.status
}
and after you create the action you only have to call the step inside your workflow:
on:
pull_request: # to update newly open PRs or when a PR is synced
check_suite: # to update all PRs upon a Check Suite completion
type: ['completed']
name: Branch Guard
jobs:
branch-guard:
name: Branch Guard
if: github.event.check_suite.head_branch == 'master' || github.event.pull_request.base.ref == 'master'
runs-on: ubuntu-latest
steps:
- uses: YOUR-REP/YOUR-ACTION#v0.1
env:
GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
If you want more doc about create javascript actions
I got this example from:
Block PR merges when Checks for target branches are failing
Hope that it help you.