Angular End to End Testing with Protractor Step by step Implementation and Top 10 Questions and Answers
 Last Update:6/1/2025 12:00:00 AM     .NET School AI Teacher - SELECT ANY TEXT TO EXPLANATION.    15 mins read      Difficulty-Level: beginner

Angular End-to-End (E2E) Testing with Protractor

End-to-end (E2E) testing is a critical aspect of software development that ensures the entire application works together as expected from a user's perspective. In the context of Angular applications, E2E testing is often conducted using Protractor, an official end-to-end test framework developed by Google specifically for AngularJS applications and later extended to support Angular.

Overview of Protractor

Protractor is built on top of WebDriverJS, which itself is a JavaScript implementation of Selenium WebDriver. WebDriverJS enables browser automation and control over various browsers. By integrating WebDriverJS with Jasmine or Mocha, Protractor facilitates writing comprehensive E2E tests in a structured manner.

Setting Up Protractor for an Angular Application

  1. Install Prerequisites:

    • Node.js and npm are required to manage dependencies.
    • Angular CLI: For setting up Angular projects quickly.

  2. Initialize Protractor:

    • Navigate to your Angular project directory.
    npm install -g protractor
webdriver-manager update --standalone
ng e2e

    This command will set up Protractor configuration (protractor.conf.js) and create example tests (*.e2e-spec.ts).

  3. Configure protractor.conf.js:

    • The configuration file includes several key settings:
      • multiCapabilities: Specifies browsers against which tests will run.
      • suites: Allows grouping tests into specific sets.
      • beforeEach(), afterEach(): Hooks to execute tasks before and after each test.
      • onPrepare(): Executes once before all tests begin.
    exports.config = {
    seleniumAddress: 'http://localhost:4444/wd/hub',
    specs: ['src/**/*.e2e-spec.ts'],
    capabilities: {
        browserName: 'chrome'
    },
    baseUrl: 'http://localhost:4200',
    framework: 'jasmine',
    jasmineNodeOpts: {
        showColors: true,
        defaultTimeoutInterval: 30000,
        print: function() {}
    }
};

Writing Protractor Tests

Protractor leverages Jasmine syntax. Let’s walk through creating a simple test.

  1. Define Tests:

    // app.e2e-spec.ts
import { AppPage } from './app.po';

describe('workspace-project App', () => {
    let page: AppPage;

    beforeEach(() => {
        page = new AppPage();
    });

    it('should display welcome message', () => {
        page.navigateTo();
        expect(page.getTitleText()).toEqual('Welcome to workspace-project!');
    });
});

  2. Page Objects:

    • Page objects separate concerns between test code and HTML structure.
    // app.po.ts
import { browser, by, element } from 'protractor';

export class AppPage {
    navigateTo(): Promise<unknown> {
        return browser.get(browser.baseUrl) as Promise<unknown>;
    }

    getTitleText(): Promise<string> {
        return element(by.css('app-root .content span')).getText() as Promise<string>;
    }
}

Running Tests

  • Local Development: Run the tests locally to verify functionality.

    ng e2e

  • Continuous Integration: Integrate with CI/CD pipelines like Jenkins, GitLab CI, Travis CI, etc., for automated testing on every code push.

Key Features and Best Practices

  1. Assertions: Use Jasmine assertions to check conditions in your tests:

    expect(element.all(by.css('mat-card')).count()).toEqual(5);

  2. Element Locators: Protractor supports multiple locator strategies such as CSS, XPath, ID, Name, Class name.

    element(by.css('.user-profile'));
element(by.id('login-btn'));
element(by.name('username'));

  3. Handling Asynchronous Code: Use await and async for handling asynchronous operations.

    async getButtonText(): Promise<string> {
    const button = element(by.buttonText('Submit'));
    return await button.getText();
}

  4. Browser Navigation: Utilize navigation methods to perform operations like navigating to URLs, refreshing pages, and waiting for elements to be present.

    browser.navigate().to('/about');
browser.refresh();
browser.waitForAngularEnabled(true);

  5. Screenshots and Debugging: Capture screenshots and debug elements using browser utilities.

    browser.takeScreenshot().then(png => writeFileSync('screenshot.png', png, 'base64'));
browser.sleep(5000); // Pause for debugging

  6. Reporting and Metrics: Use tools like Allure Reports or Jasmine reporters to generate detailed test reports.

Conclusion

Protractor plays a pivotal role in Angular E2E testing by providing robust automation capabilities and a seamless integration with Angular’s rendering engine. By leveraging its features and best practices, developers can ensure applications not only work correctly but also maintain high-quality standards across different environments. Comprehensive E2E testing enhances user satisfaction and reduces the effort needed in identifying and fixing bugs.




Angular End-to-End Testing with Protractor: A Step-by-Step Guide for Beginners

End-to-end (E2E) testing is a critical practice in software development, ensuring that not just individual components but the entire application works as expected. When it comes to Angular applications, Protractor has been the go-to tool for performing E2E tests. This comprehensive guide will walk you through setting up an end-to-end testing environment, configuring a test route, running the application, and understanding the data flow step-by-step.

1. Setting Up Protractor for Angular Projects

Prerequisites:

  • Node.js and npm installed on your machine.
  • Angular CLI for generating and managing your Angular project.

First, you need to set up a new Angular project or continue with an existing one. To create a new project, use the Angular CLI:

ng new my-angular-app
cd my-angular-app

Now, install Protractor globally or within your project:

# Install globally
npm install -g protractor

# OR install locally
npm install --save-dev protractor

Next, you'll need to update Protractor's configuration files:

# Pulls in dependent packages
npm run webdriver-manager update

# Set up Protractor configuration file in your project.
ng e2e --config e2e/protractor.conf.js

2. Configure Protractor Configuration File

The configuration file is critical for setting up E2E testing parameters. It lives in the e2e directory and is named protractor.conf.js. You can customize this file according to your needs, specifying browser types, specs to run, and timeouts.

exports.config = {
  allScriptsTimeout: 11000,
  specs: [
    './**/*.e2e-spec.ts'
  ],
  capabilities: {
    'browserName': 'chrome'
  },
  directConnect: true,
  SELENIUM_PROMISE_MANAGER: false,
  baseUrl: 'http://localhost:4200/',
  framework: 'jasmine',
  jasmineNodeOpts: {
    showColors: true,
    defaultTimeoutInterval: 30000,
    print: function() {}
  },
  onPrepare() {
    require('ts-node').register({
      project: require('path').join(__dirname, './tsconfig.json')
    });
    jasmine.getEnv().addReporter(new SpecReporter({ spec: { displayStacktrace: true } }));
  }
};

3. Defining Test Routes and Application Interactions

For setting test routes, let's assume we has a basic Angular application with a component that displays a list of items fetched from a mock API. The route can be configured in your app-routing.module.ts:

import { NgModule } from '@angular/core';
import { Routes, RouterModule } from '@angular/router';
import { ItemsComponent } from './items/items.component';

const routes: Routes = [
  { path: 'items', component: ItemsComponent },
  { path: '', redirectTo: '/items', pathMatch: 'full' }
];

@NgModule({
  imports: [RouterModule.forRoot(routes)],
  exports: [RouterModule]
})
export class AppRoutingModule { }

In your items.component.spec.ts file, write the E2E test that navigates to this route and performs actions:

import { browser, logging, element, by } from 'protractor';

describe('Items Component Tests', () => {
  beforeEach(async () => {
    await browser.get(browser.baseUrl + '/items');
  });

  it('should display a list of items', async () => {
    let items = element.all(by.css('app-item'));
    expect(await items.count()).toBe(10);
  });

  it('should add a new item', async () => {
    let addItemButton = element(by.buttonText('Add Item'));
    await addItemButton.click();

    let items = element.all(by.css('app-item'));
    expect(await items.count()).toBe(11);
  });

  afterEach(async () => {
    // Assert that there are no errors emitted from the browser
    const logs = await browser
      .manage()
      .logs()
      .get(logging.Type.BROWSER);
    expect(logs).not.toContain(
      jasmine.objectContaining({
        level: logging.Level.SEVERE,
      } as logging.Entry)
    );
  });
});

4. Running the Application and E2E Tests

To run the application, use the ng serve command. Then, open a new terminal window to execute Protractor:

# Start the application
ng serve

# Run E2E tests
ng e2e

5. Understanding the Data Flow

  • Configuration: The protractor.conf.js file configures Protractor to run tests against the application.
  • Navigation: browser.get navigates to specific routes within your application.
  • Elements Interaction: element(by.css, by.buttonText...) selects and interacts with elements in the browser DOM.
  • Assertions: expect(...).toBe(...) validates interactions with the application.

When you run the tests, Protractor will simulate user actions on the web application, check the behavior, and report any discrepancies. This is essential for understanding how your application interacts under different conditions.

Conclusion

By following this step-by-step guide, you've learned how to set up an end-to-end testing environment using Protractor for an Angular application. This knowledge will help ensure that your Angular applications are robust, reliable, and meet the required standards. Regular execution of E2E tests will provide you with confidence in your application's performance and functionality. Happy testing!




Certainly! Below is a structured list of the "Top 10 Questions and Answers" on the topic "Angular End-to-End (E2E) Testing with Protractor," covering essential concepts and practical aspects.

Top 10 Questions and Answers on Angular End-to-End Testing with Protractor

1. What is Protractor, and why is it used for Angular applications?

Answer: Protractor is a Node.js program built on top of WebDriverJS, which is the official WebDriver for Selenium. It is specifically designed for Angular applications, offering a robust set of features to test Angular-specific components like ng-repeats, bindings, and more. Protractor automatically synchronizes tests with the execution of Angular app processes, ensuring that tests only run once the app is stable.

2. How do I set up Protractor for an Angular project?

Answer: Setting up Protractor for an Angular project involves several steps:

  • Install Node.js and npm: Ensure you have Node.js and npm installed globally on your system.
  • Install Angular CLI: Use npm install -g @angular/cli to install Angular CLI if you haven't already.
  • Create a New Angular Project: Use ng new my-angular-app to create a new project.
  • Navigate to the Project Directory: cd my-angular-app.
  • Install Protractor: Run npm install --save-dev protractor.
  • Update Protractor Configuration: Use the command npx protractor --init to generate a protractor.conf.js.
  • Install WebDriver Manager: Execute npm install -g webdriver-manager to install WebDriver Manager.
  • Update Selenium: Run npx webdriver-manager update to download the necessary files.
  • Start Selenium Server: Launch npx webdriver-manager start.
  • Run Protractor: Execute npx protractor protractor.conf.js to run your E2E tests.

3. What is a Page Object Model (POM) in Protractor, and why should you use it?

Answer: The Page Object Model (POM) in Protractor allows you to create object representations of your web pages that you can use to interact with the elements on those pages. Each page of your web application is represented as a class, with methods to select elements and interact with them. POM helps in maintaining clean and readable tests by encapsulating page-specific actions and elements. Benefits include easier maintenance, reuse, and readability of tests.

4. How do you write a basic Protractor test to check if an element is displayed on a page?

Answer: Here’s a simple Protractor test to check if an element is displayed:

describe('Angular Home Page', function() {
    it('should display the title', function() {
        browser.get('https://angular.io/');

        var title = element(by.css('title'));
        expect(title.getText()).toEqual('Angular - The Platform for Amazing Web Applications');
    });

    it('should check if the Angular logo is visible', function() {
        var logo = element(by.css('.logo'));
        expect(logo.isDisplayed()).toBe(true);
    });
});

5. Describe some strategies for handling asynchronous operations in Protractor.

Answer: Handling asynchronous operations is crucial in Angular E2E testing with Protractor due to dynamic webpage content. Here are some strategies:

  • Using browser.waitForAngular(): This method waits for Angular to finish rendering and updating the DOM.

  • Using browser.sleep(ms): While a temporary solution, explicitly waiting for a fixed amount of time can help in cases where no other synchronization mechanism works.

  • Using element.all(by.repeater()): When dealing with looping constructs like ng-repeat, waiting for elements to be present can be handled using element.all() methods.

  • Using browser.userIdlePromise: This allows you to wait for specific conditions in the Angular application before proceeding with tests.

6. How can I handle alerts, popups, and modals in Protractor tests?

Answer: Protractor provides the browser.switchTo() method to handle different elements like alerts, popups, and modals:

  • Alerts:

    // Accept an alert
browser.switchTo().alert().accept(); 

// Dismiss an alert
browser.switchTo().alert().dismiss();

  • Confirmations:

    // Accept a confirmation
browser.switchTo().alert().accept(); 

// Dismiss a confirmation
browser.switchTo().alert().dismiss();

  • Prompts:

    // Set text in a prompt
browser.switchTo().alert().sendKeys('Your text here');

// Accept a prompt
browser.switchTo().alert().accept();

7. How do you parameterize tests in Protractor?

Answer: Parameterizing tests in Protractor involves running the same test suite with different input values. You can achieve this using the jasmine-data-provider library. Here’s an example:

First, install jasmine-data-provider:

npm install jasmine-data-provider --save-dev

Then, use it in your test script:

const using = require('jasmine-data-provider');

describe('Parameterized Test Example', function() {
    var data = {
        positiveTest: {a: 2, b: 3, expected: 5},
        negativeTest: {a: -2, b: -3, expected: -5}
    };

    using(data, function(test) {
        it("add two numbers " + test.a + " and " + test.b, function() {
            browser.get('http://your-test-page.com');

            var input1 = element(by.css('#input1'));
            var input2 = element(by.css('#input2'));
            var result = element(by.css('#result'));

            input1.sendKeys(test.a);
            input2.sendKeys(test.b);
            element(by.css('#addButton')).click();
            
            expect(result.getText()).toEqual(test.expected.toString());
        });
    });
});

8. What are some best practices while writing E2E tests with Protractor?

Answer: Best practices include:

  • Maintainability: Use Page Object Model (POM) architecture.
  • Modularity: Break tests into smaller, reusable components.
  • Readability: Write easy-to-understand, well-documented tests.
  • Performance: Avoid excessive sleep() statements; use synchronization features.
  • Scalability: Ensure tests can scale with the application.
  • Isolation: Test individual components independently.
  • Test Data: Use mock data where necessary.
  • Run Environment: Test in environments similar to production.

9. How do you handle non-Angular pages with Protractor?

Answer: Protractor is designed for Angular applications, but it can handle non-Angular applications by disabling Angular synchronization:

describe('Non-Angular Page', function() {
    beforeAll(function() {
        browser.ignoreSynchronization = true;
    });

    it('should navigate to a non-Angular page', function() {
        browser.get('https://example.com');

        var title = element(by.css('title'));
        expect(title.getText()).toEqual('Example Domain');
    });

    afterAll(function() {
        browser.ignoreSynchronization = false;
    });
});

Setting browser.ignoreSynchronization to true allows Protractor to interact with non-Angular web pages.

10. Can Protractor be integrated with CI/CD pipelines?

Answer: Absolutely! Protractor tests can be integrated into CI/CD pipelines using tools like Jenkins, Travis CI, CircleCI, and more. Integration typically involves:

  • Headless Browsers: Use headless browsers like Chrome or Firefox to run tests without displaying the GUI.
  • CI/CD Tools: Set up a CI/CD pipeline to automate test execution, reporting, and deployment.
  • Test Reports: Generate test reports using tools like Jasmine HTML reporter or Allure Reports.

Here’s a simple Jenkins pipeline script to run Protractor tests:

pipeline {
    agent any
    stages {
        stage('Install Dependencies') {
            steps {
                sh 'npm install'
            }
        }
        stage('Run Protractor Tests') {
            steps {
                sh 'npx protractor protractor.conf.js'
            }
        }
    }
    post {
        always {
            junit 'e2e/**/*.xml'
        }
    }
}

Integrating Protractor with CI/CD pipelines ensures continuous testing and helps in identifying issues early in the development cycle.