ThrottlingFilter
Limits the rate that requests pass through a filter. The maximum number of requests that a client is allowed to make in a defined time is called the throttling rate.
When the throttling rate is reached, PingGateway issues an HTTP status code
429 Too Many Requests
and a Retry-After
header, whose value is rounded up
to the number of seconds to wait before trying the request again.
GET http://ig.example.com:8080/home/throttle-scriptable HTTP/1.1
. . .
HTTP/1.1 429 Too Many Requests
Retry-After: 10
Usage
{
"name": string,
"type": "ThrottlingFilter",
"config": {
"requestGroupingPolicy": runtime expression<string>,
"throttlingRatePolicy": ThrottlingPolicy reference, //Use either "throttlingRatePolicy"
"rate": { //or "rate", but not both.
"numberOfRequests": configuration expression<number>,
"duration": configuration expression<duration>
},
"cleaningInterval": configuration expression<duration>,
"executor": ScheduledExecutorService reference
}
}
Properties
"requestGroupingPolicy"
: runtime expression<string>, optional-
An expression to identify the partition to use for the request. In many cases the partition identifies an individual client that sends requests, but it can also identify a group that sends requests. The expression can evaluate to the client IP address or user ID, or an OpenID Connect subject/issuer.
The value for this expression must not be null.
Default: Empty string; all requests share the same partition
See also Expressions.
"throttlingRatePolicy"
: ThrottlingPolicy reference, required ifrate
is not used-
A reference to, or inline declaration of, a policy to apply for throttling rate. The following policies can be used:
This value for this parameter must not be null.
"rate"
: object, required ifthrottlingRatePolicy
is not used-
The throttling rate to apply to requests. The rate is calculated as the number of requests divided by the duration:
"numberOfRequests"
: configuration expression<integer>, required-
The number of requests allowed through the filter in the time specified by
"duration"
.
"duration"
: configuration expression<duration>, required-
A time interval during which the number of requests passing through the filter is counted.
"cleaningInterval"
: configuration expression<duration>, optional-
The time to wait before cleaning outdated partitions. The value must be more than zero but not more than one day.
"executor"
: ScheduledExecutorService reference, optional-
An executor service to schedule the execution of tasks, such as the clean up of partitions that are no longer used.
Default:
ScheduledExecutorService
See also ScheduledExecutorService.
Examples
The following route defines a throttling rate of 6 requests/10 seconds to requests. For information about how to set up and test this example, refer to Configure Simple Throttling.
{
"name": "00-throttle-simple",
"baseURI": "http://app.example.com:8081",
"condition": "${find(request.uri.path, '^/home/throttle-simple')}",
"handler": {
"type": "Chain",
"config": {
"filters": [
{
"type": "ThrottlingFilter",
"name": "ThrottlingFilter-1",
"config": {
"requestGroupingPolicy": "",
"rate": {
"numberOfRequests": 6,
"duration": "10 s"
}
}
}
],
"handler": "ReverseProxyHandler"
}
}
}