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Question 28 of 100
Intermediate API Testing
Intermediate
Q28: What is API Key Authentication? How do you Implement it in Postman?
🔑Core Concept
What is API Key Authentication? How do you Implement it in Postman?
Key Takeaways & Architecture Summary
- ✓API Keys are static, unique strings assigned to a specific developer or client app.
- ✓Can be passed as Query Parameters (e.g. ?apikey=key) or Custom Headers.
- ✓Excellent for usage tracking, rate limiting, and API billing metrics.
Direct Answer Summary
API Key Authentication restricts access to identified clients using a static, unique string token. This key is passed either in a query parameter or inside a custom header (e.g., `x-api-key`). In Postman, you configure this in the Authorization tab under "API Key", defining the key name, key value, and whether it belongs in the header or query string.
⚠️ Senior Engineering Warning (Red Flag)
Do not commit your API keys to public Git repositories. Automated scanner bots scrape repositories constantly, stealing keys and incurring significant usage costs.
💡 STAR Architectural Explanation & Pro Tip
API keys are primarily used for client identification rather than secure user authorization. They allow gateways to track usage limits, manage rate-limiting, and bill developer plans.
PlaywrightApiTest.ts
Playwright API// Injecting API Key in Custom Header using Playwright
await request.get('/api/v1/jobs', {
headers: {
'x-api-key': 'usr_active_9028402a0df8a01'
}
});