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API Security Testing
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Q70: What is Rate Limiting in APIs? How Do You Test It?
⏱️Core Concept
What is Rate Limiting in APIs? How Do You Test It?
Key Takeaways & Architecture Summary
- ✓Controls request volume by limiting client calls over specific intervals.
- ✓Protects APIs from resource starvation, scraping, and brute force.
- ✓Returns HTTP 429 Too Many Requests once rate limits are breached.
Direct Answer Summary
Rate Limiting restricts the number of API requests a client can make within a specified timeframe (e.g., 60 requests per minute). To test this, you write automated loop scripts to bombard the endpoint with requests, verifying that once the threshold is crossed, the server returns an HTTP 429 status code.
⚠️ Senior Engineering Warning (Red Flag)
Never leave public APIs without rate limits. An attacker can write simple loop scripts to send millions of requests in seconds, crashing your backend database servers.
💡 STAR Architectural Explanation & Pro Tip
Servers communicate rate limits using standard headers: `X-RateLimit-Limit` (quota limits), `X-RateLimit-Remaining` (remaining quota), and `Retry-After` (wait time before retrying).
RestAssuredTest.java
Rest-Assured + Java// Rest-Assured script: Verifying API Rate Limiting yields HTTP 429
int totalRequests = 100;
for (int i = 0; i < totalRequests; i++) {
Response response = RestAssured.get("/api/v1/jobs");
if (response.statusCode() == 429) {
System.out.println("Rate limit successfully triggered at request " + i);
break; // Assertions passed
}
}