Skip to main content
Version: 2.9

limit-count

Summary#

Name#

Limit request rate by a fixed number of requests in a given time window.

Attributes#

NameTypeRequirementDefaultValidDescription
countintegerrequiredcount > 0the specified number of requests threshold.
time_windowintegerrequiredtime_window > 0the time window in seconds before the request count is reset.
keystringoptional"remote_addr"["remote_addr", "server_addr", "http_x_real_ip", "http_x_forwarded_for", "consumer_name", "service_id"]The user specified key to limit the count.
Now accept those as key: "remote_addr"(client's IP), "server_addr"(server's IP), "X-Forwarded-For/X-Real-IP" in request header, "consumer_name"(consumer's username) and "service_id".
rejected_codeintegeroptional503[200,...,599]The HTTP status code returned when the request exceeds the threshold is rejected, default 503.
rejected_msgstringoptionalnon-emptyThe response body returned when the request exceeds the threshold is rejected.
policystringoptional"local"["local", "redis", "redis-cluster"]The rate-limiting policies to use for retrieving and incrementing the limits. Available values are local(the counters will be stored locally in-memory on the node), redis(counters are stored on a Redis server and will be shared across the nodes, usually use it to do the global speed limit), and redis-cluster which works the same as redis but with redis cluster.
allow_degradationbooleanoptionalfalseWhether to enable plugin degradation when the limit-count function is temporarily unavailable(e.g. redis timeout). Allow requests to continue when the value is set to true, default false.
show_limit_quota_headerbooleanoptionaltrueWhether show X-RateLimit-Limit and X-RateLimit-Remaining (which mean the total number of requests and the remaining number of requests that can be sent) in the response header, default true.
redis_hoststringrequired for redisWhen using the redis policy, this property specifies the address of the Redis server.
redis_portintegeroptional6379[1,...]When using the redis policy, this property specifies the port of the Redis server.
redis_passwordstringoptionalWhen using the redis or redis-cluster policy, this property specifies the password of the Redis server.
redis_databaseintegeroptional0redis_database >= 0When using the redis policy, this property specifies the database you selected of the Redis server, and only for non Redis cluster mode (single instance mode or Redis public cloud service that provides single entry).
redis_timeoutintegeroptional1000[1,...]When using the redis or redis-cluster policy, this property specifies the timeout in milliseconds of any command submitted to the Redis server.
redis_cluster_nodesarrayrequired when policy is redis-clusterWhen using redis-cluster policy,This property is a list of addresses of Redis cluster service nodes (at least two).
redis_cluster_namestringrequired when policy is redis-clusterWhen using redis-cluster policy, this property is the name of Redis cluster service nodes.

Key can be customized by the user, only need to modify a line of code of the plug-in to complete. It is a security consideration that is not open in the plugin.

How To Enable#

Here's an example, enable the limit count plugin on the specified route:

curl -i http://127.0.0.1:9080/apisix/admin/routes/1 -H 'X-API-KEY: edd1c9f034335f136f87ad84b625c8f1' -X PUT -d '{    "uri": "/index.html",    "plugins": {        "limit-count": {            "count": 2,            "time_window": 60,            "rejected_code": 503,            "key": "remote_addr"        }    },    "upstream": {        "type": "roundrobin",        "nodes": {            "39.97.63.215:80": 1        }    }}'

You can open dashboard with a browser: http://127.0.0.1:9080/apisix/dashboard/, to complete the above operation through the web interface, first add a route: Add a router.

Then add limit-count plugin: Add limit-count plugin.

If you need a cluster-level precision traffic limit, then we can do it with the redis server. The rate limit of the traffic will be shared between different APISIX nodes to limit the rate of cluster traffic.

Here is the example if we use single redis policy:

curl -i http://127.0.0.1:9080/apisix/admin/routes/1 -H 'X-API-KEY: edd1c9f034335f136f87ad84b625c8f1' -X PUT -d '{    "uri": "/index.html",    "plugins": {        "limit-count": {            "count": 2,            "time_window": 60,            "rejected_code": 503,            "key": "remote_addr",            "policy": "redis",            "redis_host": "127.0.0.1",            "redis_port": 6379,            "redis_password": "password",            "redis_database": 1,            "redis_timeout": 1001        }    },    "upstream": {        "type": "roundrobin",        "nodes": {            "39.97.63.215:80": 1        }    }}'

If using redis-cluster policy:

curl -i http://127.0.0.1:9080/apisix/admin/routes/1 -H 'X-API-KEY: edd1c9f034335f136f87ad84b625c8f1' -X PUT -d '{    "uri": "/index.html",    "plugins": {        "limit-count": {            "count": 2,            "time_window": 60,            "rejected_code": 503,            "key": "remote_addr",            "policy": "redis-cluster",            "redis_cluster_nodes": [              "127.0.0.1:5000",              "127.0.0.1:5001"            ],            "redis_password": "password",            "redis_cluster_name": "redis-cluster-1"        }    },    "upstream": {        "type": "roundrobin",        "nodes": {            "39.97.63.215:80": 1        }    }}'

Test Plugin#

The above configuration limits access to only 2 times in 60 seconds. The first two visits will be normally:

curl -i http://127.0.0.1:9080/index.html

The response header contains X-RateLimit-Limit and X-RateLimit-Remaining, which mean the total number of requests and the remaining number of requests that can be sent:

HTTP/1.1 200 OKContent-Type: text/htmlContent-Length: 13175Connection: keep-aliveX-RateLimit-Limit: 2X-RateLimit-Remaining: 0Server: APISIX web server

When you visit for the third time, you will receive a response with the 503 HTTP code:

HTTP/1.1 503 Service Temporarily UnavailableContent-Type: text/htmlContent-Length: 194Connection: keep-aliveServer: APISIX web server
<html><head><title>503 Service Temporarily Unavailable</title></head><body><center><h1>503 Service Temporarily Unavailable</h1></center><hr><center>openresty</center></body></html>

At the same time, if you set the property rejected_msg to "Requests are too frequent, please try again later." , when you visit for the third time, you will receive a response body like below:

HTTP/1.1 503 Service Temporarily UnavailableContent-Type: text/htmlContent-Length: 194Connection: keep-aliveServer: APISIX web server
{"error_msg":"Requests are too frequent, please try again later."}

This means that the limit count plugin is in effect.

Disable Plugin#

When you want to disable the limit count plugin, it is very simple, you can delete the corresponding json configuration in the plugin configuration, no need to restart the service, it will take effect immediately:

curl http://127.0.0.1:9080/apisix/admin/routes/1 -H 'X-API-KEY: edd1c9f034335f136f87ad84b625c8f1' -X PUT -d '{    "methods": ["GET"],    "uri": "/index.html",    "upstream": {        "type": "roundrobin",        "nodes": {            "39.97.63.215:80": 1        }    }}'

The limit count plugin has been disabled now. It works for other plugins.