APISIX Rate Limiting Guide: Protect Your APIs

Introduction

Rate limiting is a crucial feature for protecting APIs from abuse and ensuring fair usage among clients. APISIX provides powerful rate limiting plugins that help you control the flow of requests to your APIs. This guide will show you how to implement various rate limiting strategies in APISIX.

Prerequisites

• APISIX installed and configured
• Basic understanding of API Gateway concepts
• Access to APISIX Admin API or Dashboard

1. Basic Rate Limiting

The simplest form of rate limiting in APISIX is using the limit-count plugin. Here's how to limit requests to 5 per minute:

{
  "plugins": {
    "limit-count": {
      "count": 5,
      "time_window": 60,
      "rejected_code": 429,
      "key_type": "var",
      "key": "remote_addr"
    }
  },
  "uri": "/limited-api/*"
}

2. Advanced Rate Limiting Strategies

2.1 Consumer-based Rate Limiting

{
  "plugins": {
    "limit-count": {
      "count": 100,
      "time_window": 3600,
      "key_type": "consumer_name",
      "rejected_code": 429
    }
  }
}

2.2 Sliding Window Rate Limiting

{
  "plugins": {
    "limit-req": {
      "rate": 1,
      "burst": 2,
      "key_type": "var",
      "key": "remote_addr",
      "rejected_code": 429
    }
  }
}

3. Rate Limiting Response Headers

APISIX adds the following headers to responses when rate limiting is active:

• X-RateLimit-Limit: Maximum requests allowed
• X-RateLimit-Remaining: Remaining requests in the current window
• X-RateLimit-Reset: Time until the limit resets

4. Implementing Different Rate Limits by Route

You can set different rate limits for different API routes:

{
  "routes": [
    {
      "uri": "/public/*",
      "plugins": {
        "limit-count": {
          "count": 10,
          "time_window": 60
        }
      }
    },
    {
      "uri": "/premium/*",
      "plugins": {
        "limit-count": {
          "count": 1000,
          "time_window": 60
        }
      }
    }
  ]
}

5. Best Practices

• Start with conservative limits and adjust based on usage patterns
• Implement rate limiting alongside authentication
• Use different limits for different types of users/clients
• Monitor rate limiting metrics to identify potential issues
• Provide clear documentation about rate limits to API consumers

6. Monitoring Rate Limiting

APISIX provides metrics for monitoring rate limiting through its Prometheus integration:

# Example Prometheus query
apisix_http_status{code="429"}

Conclusion

Rate limiting is essential for protecting your APIs and ensuring fair usage. APISIX provides flexible rate limiting options that can be tailored to your specific needs. Remember to monitor your rate limits and adjust them based on real-world usage patterns.

View APISIX Documentation on GitHub

Read Next