Playwright (TS) – API tests error on a ‘401’, but only within one spec file

If you’re reading this, chances are you’re stuck in a frustrating situation where your API tests are failing with a 401 error, but only in one specific spec file. Don’t worry, you’re not alone! In this article, we’ll delve into the world of Playwright and TypeScript to help you troubleshoot and resolve this pesky issue.

What’s going on?

Before we dive into the solution, let’s understand the problem. A 401 error typically indicates that the request lacks valid authentication credentials. But why is it happening only in one spec file? There are a few possible reasons for this:

• Incorrect or outdated authentication credentials
• Misconfigured API endpoint or base URL
• Specific headers or query parameters required only for that endpoint
• Environmental variables or context issues

Let’s investigate!

To begin, let’s create a simple API test using Playwright and TypeScript. We’ll use the following example:

import { test, expect } from '@playwright/test';

test('API test', async ({ request }) => {
  const response = await request.get('https://api.example.com/data');
  expect(response.status()).toBe(200);
});

Run this test, and you should see it passing successfully. Now, let’s introduce the 401 error by removing or updating the authentication credentials:

import { test, expect } from '@playwright/test';

test('API test', async ({ request }) => {
  const response = await request.get('https://api.example.com/data', {
    headers: {
      'Authorization': 'Bearer INVALID_TOKEN'
    }
  });
  expect(response.status()).toBe(200); // This will fail with a 401 error
});

Troubleshooting steps

Now that we’ve reproduced the issue, let’s go through some troubleshooting steps to identify the root cause:

1. Verify authentication credentials

Double-check your authentication credentials, such as API keys, tokens, or usernames and passwords. Ensure they are correct, up-to-date, and properly configured.

import { test, expect } from '@playwright/test';

test('API test', async ({ request }) => {
  const token = 'VALID_TOKEN';
  const response = await request.get('https://api.example.com/data', {
    headers: {
      'Authorization': `Bearer ${token}`
    }
  });
  expect(response.status()).toBe(200);
});

2. Check API endpoint and base URL

Verify that the API endpoint and base URL are correct. Sometimes, a simple typo or incorrect configuration can lead to authentication issues.

import { test, expect } from '@playwright/test';

test('API test', async ({ request }) => {
  const baseUrl = 'https://api.example.com/v2';
  const response = await request.get(`${baseUrl}/data`);
  expect(response.status()).toBe(200);
});

3. Inspect request headers and query parameters

Examine the request headers and query parameters being sent with the request. You might be missing a required header or query parameter that’s specific to that endpoint.

import { test, expect } from '@playwright/test';

test('API test', async ({ request }) => {
  const response = await request.get('https://api.example.com/data', {
    headers: {
      'Authorization': 'Bearer VALID_TOKEN',
      'X-API-VERSION': '2.0'
    },
    params: {
      'filter': 'active'
    }
  });
  expect(response.status()).toBe(200);
});

4. Review environmental variables and context

Make sure that any environmental variables or context-related configuration is correct and applied correctly. You might need to update your test configuration or setup files.

import { test, expect } from '@playwright/test';

test('API test', async ({ request, context }) => {
  const token = context.token;
  const response = await request.get('https://api.example.com/data', {
    headers: {
      'Authorization': `Bearer ${token}`
    }
  });
  expect(response.status()).toBe(200);
});

Solving the mystery

By following these troubleshooting steps, you should be able to identify and resolve the issue causing the 401 error in your API test. Remember to:

• Verify authentication credentials
• Check API endpoint and base URL
• Inspect request headers and query parameters
• Review environmental variables and context

If you’re still stuck, consider the following:

• Check the API documentation for specific requirements or restrictions
• Use debugging tools, such as Chrome DevTools or Playwright’s built-in debugging features
• Consult with your team or API developers for potential issues or changes

Conclusion

We’ve walked through the common causes and troubleshooting steps to resolve the 401 error in your API test using Playwright and TypeScript. By following these guidelines, you should be able to identify and fix the issue, getting your tests back on track.

Troubleshooting Step	Description
Verify authentication credentials	Check API keys, tokens, usernames, and passwords for correctness and updates
Check API endpoint and base URL	Verify correctness of API endpoint and base URL configuration
Inspect request headers and query parameters	Examine request headers and query parameters for required headers or parameters
Review environmental variables and context	Ensure correct configuration and application of environmental variables and context

Remember, patience and persistence are key when troubleshooting issues in your API tests. Take your time, and with these steps, you’ll be back to writing successful tests in no time!

Frequently Asked Question

Are you stuck with API tests error on a ‘401’ within one spec file using Playwright (TS)? Worry not, we’ve got you covered! Here are some frequently asked questions and answers to help you troubleshoot the issue.