Skip unnecessary builds on GitHub actions

Motivation

The initial problem that I faced was building both the front end and the back end from the same project folder. Sometimes only one of them is changed or even none of them and only the documentation. In such cases, the relevant build should be skipped.

Prerequisites

GitHub actions are used to build the project.

Solution

backend-workflow.yml

name: backend

on:
  pull_request:
    types: [ synchronize, opened, reopened, ready_for_review ]

jobs:
  backend:
    runs-on: ubuntu-latest
    if: github.event.pull_request.draft == false
    steps:
      - name: Checkout the Project
        uses: actions/checkout@v2
      - name: Skip the Build
        id: skip_build
        uses: fkirc/skip-duplicate-actions@master
        with:
          paths: '["backend/gradle/**", "backend/src/**", "backend/build.gradle", "backend/gradle.properties", "backend/settings.gradle"]'
      - name: Set up JDK 1.8
        if: ${{ steps.skip_build.outputs.should_skip != 'true' }}
        uses: actions/setup-java@v1
        with:
          java-version: 1.8
      # Any further step should have the IF-check as it's used in the previous step

frontend-workflow.yml

name: frontend

on:
  pull_request:
    types: [ synchronize, opened, reopened, ready_for_review ]

jobs:
  frontend:
    runs-on: ubuntu-latest
    if: github.event.pull_request.draft == false
    steps:
      - name: Checkout the Project
        uses: actions/checkout@v2
      - name: Skip the Build
        id: skip_build
        uses: fkirc/skip-duplicate-actions@master
        with:
          paths: '["frontend/src/**", "frontend/package.json"]'
      - name: Setup Node.js environment
        if: ${{ steps.skip_build.outputs.should_skip != 'true' }}
        uses: actions/setup-node@v1
        with:
          node-version: 12
      # Any further step should have the IF-check as it's used in the previous step

Motivation

Prerequisites

Solution

Further reading