SFD-89 Create merge pipeline (#60)

* Add merge pipeline

* Add build job

* Add build dependency to unit_tests job

* Add dependency caching

* Cache ~/.npm rather than node_modules

* Move environment setup to custom action

* Use set-up-environment action in pages workflow

* Add unit tests to deployment pipeline

* Add documentation about skipping workflows on pushes to a PR branch

.github/actions/set-up-environment/action.yml

@@ -0,0 +1,17 @@
+name: 'Set up environment'
+description: 'Sets up Node and installs dependencies'
+runs:
+  using: 'composite'
+  steps:
+    - name: Set up Node
+      uses: actions/setup-node@v4
+      with:
+        node-version: 18
+    - name: Cache dependencies
+      uses: actions/cache@v4
+      with:
+        path: ~/.npm
+        key: node-modules-${{ hashFiles('**/package-lock.json') }}
+    - name: Install dependencies
+      run: npm ci
+      shell: bash

.github/workflows/pages.yml

@@ -3,7 +3,7 @@ name: Deploy estimator Pages
 on:
   # Runs on pushes targeting the default branch
   push:
-    branches: ["main"]
+    branches: ['main']
 
   # Allows you to run this workflow manually from the Actions tab
   workflow_dispatch:
@@ -17,33 +17,42 @@ permissions:
 # Allow only one concurrent deployment, skipping runs queued between the run in-progress and latest queued.
 # However, do NOT cancel in-progress runs as we want to allow these production deployments to complete.
 concurrency:
-  group: "pages"
+  group: 'pages'
   cancel-in-progress: false
 
 jobs:
   # Build job
   build:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
-      - name: Setup Node
-        uses: actions/setup-node@v4
-        with:
-          node-version: '18'
-      - run: npm install
+      - name: Check out code
+        uses: actions/checkout@v4
+      - name: Set up environment
+        uses: ./.github/actions/set-up-environment
       - name: Build app
         run: npm run build
       - name: Upload artifact
         uses: actions/upload-pages-artifact@v3
         with:
           path: ./dist/tech-carbon-estimator
 
+  unit_tests:
+    needs: build
+    runs-on: ubuntu-latest
+    steps:
+      - name: Check out code
+        uses: actions/checkout@v4
+      - name: Set up environment
+        uses: ./.github/actions/set-up-environment
+      - name: Run tests
+        run: npm test
+
   deploy:
     environment:
       name: github-pages
       url: ${{ steps.deployment.outputs.page_url }}
     runs-on: ubuntu-latest
-    needs: build
+    needs: unit_tests
     steps:
       - name: Deploy to GitHub Pages
         id: deployment

.github/workflows/pull-request.yml

@@ -0,0 +1,23 @@
+name: PR Workflow
+on: pull_request
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Check out code
+        uses: actions/checkout@v4
+      - name: Set up environment
+        uses: ./.github/actions/set-up-environment
+      - name: Build app
+        run: npm run build
+  unit_tests:
+    needs: build
+    runs-on: ubuntu-latest
+    steps:
+      - name: Check out code
+        uses: actions/checkout@v4
+      - name: Set up environment
+        uses: ./.github/actions/set-up-environment
+      - name: Run tests
+        run: npm test

README.md

@@ -42,6 +42,10 @@ Run `ng build` to build the project. The build artifacts will be stored in the `
 
 Run `ng test` to execute the unit tests via [Karma](https://karma-runner.github.io).
 
+## GitHub Actions
+
+The project uses [GitHub Actions](https://docs.github.com/en/actions) to automate certain workflows. One such workflow runs when opening a pull request and pushing changes to the related branch. If you would like to skip running the workflow for a given push to a PR branch there are [various ways](https://docs.github.com/en/actions/managing-workflow-runs/skipping-workflow-runs) this can be achieved. For example, adding `[skip ci]` to the end of the commit message in the push (e.g. `git commit -m "My message [skip ci]"`) will skip running the workflow for that push.
+
 ## Further help
 
 To get more help on the Angular CLI use `ng help` or go check out the [Angular CLI Overview and Command Reference](https://angular.io/cli) page.