Playwright Frontend Testing

End-to-end testing for vanilla JavaScript frontends using Playwright Java with Chromium.

Quick Start

# Ensure Playwright installed (one-time setup)
mvn exec:java -e -D exec.mainClass=com.microsoft.playwright.CLI -D exec.args="install --with-deps chromium"

# Run all frontend tests
mvn test -Dtest="*FrontendTest"

# Run specific test
mvn test -Dtest="V1DashboardFrontendTest"

# Debug with visible browser
HEADED=true mvn test -Dtest="V1DashboardFrontendTest"

Test Structure

Test class:

• Extends: AbstractFrontendTest (provides browser, page, baseUrl)
• Location: src/test/java/.../web/frontend/{Feature}FrontendTest.java
• Uses: @SpringBootTest(webEnvironment = RANDOM_PORT) with real backend

Page Object:

• Constructor: public PageObject(Page page, String baseUrl)
• Location: src/test/java/.../web/frontend/pages/{Feature}Page.java
• Pattern: One Page Object per HTML page

Example test:

@Test
void shouldCreateSampleWhenFormSubmitted() {
    // Given
    DashboardPage page = new DashboardPage(this.page, baseUrl);
    page.navigate();
    
    // When
    page.fillForm("Test", 42, "active");
    page.submitForm();
    
    // Then
    assertThat(page.getSuccessMessage()).contains("created");
}

Page Object Pattern

public class DashboardPage {
    private final Page page;
    private final String baseUrl;
    
    public DashboardPage(Page page, String baseUrl) {
        this.page = page;
        this.baseUrl = baseUrl;
    }
    
    public void navigate() {
        page.navigate(baseUrl + "/dashboard.html");
        page.waitForLoadState(LoadState.NETWORKIDLE);
    }
    
    public void fillForm(String text, int number, String status) {
        page.locator("#text").fill(text);
        page.locator("#number").fill(String.valueOf(number));
        page.locator("#status").selectOption(status);
    }
    
    public String getSuccessMessage() {
        Locator msg = page.locator(".message.success");
        return msg.count() > 0 ? msg.textContent() : null;
    }
}

Key Patterns

Waiting: Use Playwright's auto-waiting (built-in). For specific needs:

page.locator("#result").waitFor();  // Wait for element
page.waitForLoadState(LoadState.NETWORKIDLE);  // Wait for network

Screenshots on failure: Automatic via AbstractFrontendTest.captureScreenshotOnFailure(). Files saved to target/playwright-screenshots/.

Test isolation: Each test gets fresh BrowserContext and Page (per-test cleanup in base class).

Adding New Frontend Tests

1. Create HTML in src/main/resources/static/
2. Create Page Object in src/test/java/.../web/frontend/pages/
3. Create test class extending AbstractFrontendTest
4. Write tests following Given-When-Then pattern
5. Run: mvn test -Dtest="YourNewFrontendTest"

Configuration

Base test class:

• @TestInstance(PER_CLASS) - Browser shared across tests (performance)
• @BeforeEach - Fresh context/page per test (isolation)
• @AfterEach - Screenshot on failure, close context

Environment variables:

• HEADED=true - Run with visible browser (debugging)
• SLOWMO=1000 - Slow down actions by 1000ms (debugging)

CI Integration

Frontend tests run automatically in CI. Screenshots uploaded as artifacts on failure:

- name: Run frontend tests
  run: mvn test -Dtest="*FrontendTest"

- name: Upload screenshots on failure
  if: failure()
  uses: actions/upload-artifact@v4
  with:
    name: playwright-failure-screenshots
    path: target/playwright-screenshots/

Reference

Official docs: https://playwright.dev/java/docs/test-runners
Test examples: See src/test/java/.../web/frontend/V1DashboardFrontendTest.java
Base class: See src/test/java/.../web/frontend/AbstractFrontendTest.java