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Simulate Rate-Limit API responses

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Rate-Limit headers are used in HTTP responses to limit the number of requests that a client can make within a given time period.

The server sends these headers in response to a client's request to indicate how many requests are allowed and how many requests remain before the limit is reached.

The RateLimit-Limit response header field indicates the request-quota associated with the client in the current time-window. If the client exceeds that limit, it might not be served.

Custom rate limit support

When you exceed rate limit, some APIs use custom behaviors, such as returning a 403 Forbidden status code with a custom error message. Dev Proxy allows you to simulate these custom behaviors by using the Custom value for the whenLimitExceeded property.

The following example shows how you can configure how you can configure RateLimitingPlugin in the devproxyrc file to simulate rate limits for the GitHub API.

{
  "rateLimiting": {
    "headerLimit": "X-RateLimit-Limit",
    "headerRemaining": "X-RateLimit-Remaining",
    "headerReset": "X-RateLimit-Reset",
    "costPerRequest": 1,
    "resetTimeWindowSeconds": 3600,
    "warningThresholdPercent": 0,
    "rateLimit": 60,
    "resetFormat": "UtcEpochSeconds",
    "whenLimitExceeded": "Custom",
    "customResponseFile": "github-rate-limit-exceeded.json"
  }
}

The customResponseFile contains the response that the proxy returns when your app reached the rate limit.

{
  "statusCode": 403,
  "headers": [
    {
      "name": "Content-Type",
      "value": "application/json; charset=utf-8"
    }
  ],
  "body": {
    "message": "You have exceeded a secondary rate limit and have been temporarily blocked from content creation. Please retry your request again later.",
    "documentation_url": "https://docs.github.com/rest/overview/resources-in-the-rest-api#secondary-rate-limits"
  }
}

Next steps

Learn more about the RateLimitingPlugin.

RateLimitingPlugin