Add e2e to ci

.github/workflows/ci.yml

@@ -74,3 +74,42 @@ jobs:
           asset_path: gauge-exporter
           asset_name: gauge-exporter
           asset_content_type: application/octet-stream
+
+  e2e_test:
+    name: E2E Tests
+    runs-on: ubuntu-latest
+    needs: [compile]  # Ensure release only happens after compile
+
+    steps:
+    - uses: actions/checkout@v3
+
+    - name: Download build artifact
+      uses: actions/download-artifact@v3
+      with:
+        name: gauge-exporter
+
+    - name: Make gauge-exporter executable
+      run: chmod +x ./e2e_tests/gauge-exporter
+
+    - name: Setup PHP
+      uses: shivammathur/setup-php@v2
+      with:
+        php-version: '8.3'
+
+    - name: Cache Composer packages
+      uses: actions/cache@v3
+      with:
+        path: e2e_tests/vendor
+        key: ${{ runner.os }}-php-${{ hashFiles('**/e2e_tests/composer.lock') }}
+        restore-keys: |
+          ${{ runner.os }}-php-
+    
+    - name: Install dependencies
+      run: |
+        cd e2e_tests
+        composer install --prefer-dist -n --no-ansi
+    
+    - name: Run E2E tests
+      run: |
+        cd e2e_tests
+        ./vendor/bin/phpunit --testdox