context_limiter #

Description #

The context_limiter filter is used to control the traffic based on request context.

Configuration Example #

A configuration example is as follows:

flow:
  - name: default_flow
    filter:
      - context_limiter:
          max_requests: 1
          action: drop
          context:
            - _ctx.request.path
            - _ctx.request.header.Host
            - _ctx.request.header.Env

The above configuration combines three context variables (_ctx.request.path, _ctx.request.header.Host, and _ctx.request.header.Env) into a bucket for traffic control. The allowable maximum queries per second (QPS) is 1 per second. Subsequent requests out of the traffic control range are directly denied.

Parameter Description #

Name	Type	Description
context	array	Context variables, which form a bucket key
interval	string	Interval for evaluating whether traffic control conditions are met. The default value is `1s`.
max_requests	int	Maximum request count limit in the interval
burst_requests	int	Burst request count limit in the interval
max_bytes	int	Maximum request traffic limit in the interval
burst_bytes	int	Burst request traffic limit in the interval
action	string	Processing action after traffic control is triggered. The value can be set as `retry` or `drop` and the default value is `retry`.
status	string	Status code returned after traffic control conditions are met. The default value is `429`.
message	string	Rejection message returned for a request, for which traffic control conditions are met
retry_delay_in_ms	int	Interval for traffic control retry, in milliseconds. The default value is `10`.
max_retry_times	int	Maximum retry count in the case of traffic control retries. The default value is `1000`.
failed_retry_message	string	Rejection message returned for a request, for which the maximum retry count has been reached
log_warn_message	bool	Whether to log warn message