Waiting for requests (cy.wait with alias) in Cypress - Framework Patterns

Framework Mode - Waiting for requests (cy.wait with alias)

Folder Structure

  cypress/
  ├── e2e/
  │   ├── login.cy.js          # Test files
  │   ├── dashboard.cy.js
  │   └── apiRequests.cy.js    # Tests using cy.wait with alias
  ├── fixtures/                # Static test data
  │   └── user.json
  ├── support/
  │   ├── commands.js          # Custom commands
  │   └── e2e.js               # Global setup
  └── cypress.config.js        # Configuration file
  

Test Framework Layers

• Test Files (cypress/e2e/): Contains test scripts that use cy.intercept to spy or stub network requests and cy.wait with aliases to wait for them.
• Support Layer (cypress/support/): Holds reusable commands and global hooks to set up intercepts or common behaviors.
• Fixtures (cypress/fixtures/): Static JSON or other files used as mock data for API responses or test inputs.
• Configuration (cypress.config.js): Defines environment variables, base URLs, and browser settings.

Configuration Patterns

Use cypress.config.js to define base URLs and environment variables for different environments (dev, staging, prod). For example:

  export default defineConfig({
    e2e: {
      baseUrl: 'https://example.com',
      env: {
        apiUrl: 'https://api.example.com'
      },
      setupNodeEvents(on, config) {
        // implement node event listeners here
      }
    }
  })
  

In tests, use cy.intercept with aliases to listen for specific API calls. Use cy.wait('@alias') to pause test execution until the request finishes, ensuring stable tests.

Test Reporting and CI/CD Integration

• Use Cypress built-in reporter for test results in the terminal.
• Integrate with CI/CD pipelines (GitHub Actions, Jenkins, GitLab CI) to run tests on every push or pull request.
• Generate HTML reports using plugins like mochawesome for detailed test reports.
• Use screenshots and video recordings on test failures for easier debugging.

Best Practices

• Use cy.intercept with meaningful aliases: Name aliases clearly to reflect the request purpose, e.g., @getUser.
• Always wait for requests before asserting UI changes: Use cy.wait('@alias') to ensure the app has received data before checking results.
• Keep intercepts and waits close to the test steps: This improves readability and debugging.
• Use fixtures for consistent mock data: This helps tests be reliable and repeatable.
• Avoid arbitrary waits like cy.wait(5000): They slow tests and cause flakiness.

Self Check

Where in this folder structure would you add a new alias for waiting on the "POST /login" API request?

Key Result

Use cy.intercept with aliases and cy.wait('@alias') in test files to reliably wait for network requests.

Practice

1. What is the main purpose of using cy.wait() with an alias in Cypress tests?

easy

A. To log the test results to the console

B. To pause the test until a specific network request finishes

C. To reload the page automatically

D. To skip a test step temporarily

Solution

1. Step 1: Understand cy.wait() with alias

   The cy.wait() command pauses the test until the network request with the given alias completes.

2. Step 2: Purpose of waiting for requests

   This ensures the test runs only after the needed data is loaded, making tests reliable.

3. Final Answer:

   To pause the test until a specific network request finishes -> Option B

4. Quick Check:

   Waiting for request = pause test until done [OK]

Hint: Wait pauses test until named request finishes [OK]

Common Mistakes:

• Thinking cy.wait skips steps
• Confusing cy.wait with page reload
• Using cy.wait without alias

2. Which of the following is the correct syntax to alias a network request in Cypress?

easy

A. cy.intercept('/api/data').alias('getData')

B. cy.route('/api/data').alias('getData')

C. cy.wait('/api/data').as('getData')

D. cy.intercept('/api/data').as('getData')

Solution

1. Step 1: Identify correct alias method

   In Cypress, cy.intercept() is used to spy or stub requests, and .as() assigns an alias.

2. Step 2: Check syntax correctness

   cy.intercept('/api/data').as('getData') uses cy.intercept('/api/data').as('getData'), which is the correct syntax.

3. Final Answer:

   cy.intercept('/api/data').as('getData') -> Option D

4. Quick Check:

   Alias uses .as() after intercept [OK]

Hint: Use .as() to alias intercept, not .alias() [OK]

Common Mistakes:

• Using .alias() instead of .as()
• Trying to alias cy.wait instead of cy.intercept
• Using deprecated cy.route instead of cy.intercept

3. Given the code below, what will be the output in the test if the request takes 500ms to complete?

cy.intercept('GET', '/users').as('getUsers')
cy.visit('/users')
cy.wait('@getUsers').then(({ response }) => {
  console.log(response.status)
})

medium

A. 200

B. undefined

C. 500

D. 404

Solution

1. Step 1: Understand intercept and wait behavior

   The cy.intercept() spies on the GET request to '/users' and aliases it as 'getUsers'.

2. Step 2: Analyze the wait and response

   cy.wait('@getUsers') waits for the request to finish, then logs the response.status. A successful GET usually returns 200.

3. Final Answer:

   200 -> Option A

4. Quick Check:

   Wait logs response status 200 [OK]

Hint: Wait returns response object with status [OK]

Common Mistakes:

• Confusing request duration with status code
• Expecting wait to return undefined
• Assuming 404 if request is slow

4. Identify the error in the following Cypress test code:

cy.intercept('POST', '/login').as('loginRequest')
cy.get('button#submit').click()
cy.wait('loginRequest')

medium

A. Missing @ symbol in cy.wait alias

B. Incorrect HTTP method in intercept

C. Alias name should be in double quotes

D. cy.get selector is invalid

Solution

1. Step 1: Check cy.wait usage

   The cy.wait() command requires the alias to be prefixed with '@' to identify the request alias.

2. Step 2: Identify the error

   The code uses cy.wait('loginRequest') missing the '@', which causes Cypress to not recognize the alias.

3. Final Answer:

   Missing @ symbol in cy.wait alias -> Option A

4. Quick Check:

   Alias in cy.wait needs '@' prefix [OK]

Hint: Always prefix alias with '@' in cy.wait [OK]

Common Mistakes:

• Omitting '@' before alias in cy.wait
• Using wrong HTTP method in intercept
• Thinking quotes affect alias recognition

5. You want to test that after clicking a button, a POST request to '/submit' completes successfully before checking the page content. Which is the best way to write this in Cypress?

hard

A. cy.intercept('POST', '/submit').as('submitRequest')
cy.wait('@submitRequest')
cy.get('button#send').click()
cy.contains('Success').should('be.visible')

B. cy.get('button#send').click()
cy.wait('@submitRequest')
cy.intercept('POST', '/submit').as('submitRequest')
cy.contains('Success').should('be.visible')

C. cy.intercept('POST', '/submit').as('submitRequest')
cy.get('button#send').click()
cy.wait('@submitRequest')
cy.contains('Success').should('be.visible')

D. cy.get('button#send').click()
cy.contains('Success').should('be.visible')
cy.intercept('POST', '/submit').as('submitRequest')
cy.wait('@submitRequest')

Solution

1. Step 1: Setup intercept before action

   You must call cy.intercept() and alias before triggering the request by clicking the button.

2. Step 2: Wait for request before assertions

   Use cy.wait('@submitRequest') after clicking to pause until the POST completes, then check page content.

3. Final Answer:

   Intercept first, click, wait, then assert success message -> Option C

4. Quick Check:

   Intercept before action, wait after click [OK]

Hint: Always intercept before triggering request, then wait [OK]

Common Mistakes:

• Waiting before intercepting
• Asserting before request finishes
• Interception after click triggers request