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feat(plugin): add degradation switch for traffic control plugin (#4774)
Co-authored-by: nic-chen <[email protected]> Co-authored-by: lixingwang <[email protected]>
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15 files changed

+198
-7
lines changed

15 files changed

+198
-7
lines changed

‎apisix/plugins/limit-conn.lua‎

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@@ -33,6 +33,7 @@ local schema = {
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rejected_code = {
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type = "integer", minimum = 200, maximum = 599, default = 503
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},
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allow_degradation = {type = "boolean", default = false}
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},
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required = {"conn", "burst", "default_conn_delay", "key"}
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}

‎apisix/plugins/limit-conn/init.lua‎

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Original file line numberDiff line numberDiff line change
@@ -41,6 +41,9 @@ function _M.increase(conf, ctx)
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local lim, err = lrucache(conf, nil, create_limit_obj, conf)
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if not lim then
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core.log.error("failed to instantiate a resty.limit.conn object: ", err)
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if conf.allow_degradation then
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return
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end
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return 500
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end
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@@ -53,7 +56,10 @@ function _M.increase(conf, ctx)
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return conf.rejected_code or 503
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end
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core.log.error("failed to limit req: ", err)
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core.log.error("failed to limit conn: ", err)
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if conf.allow_degradation then
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return
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end
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return 500
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end
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‎apisix/plugins/limit-count.lua‎

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Original file line numberDiff line numberDiff line change
@@ -49,7 +49,8 @@ local schema = {
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type = "string",
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enum = {"local", "redis", "redis-cluster"},
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default = "local",
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}
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},
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allow_degradation = {type = "boolean", default = false}
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},
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required = {"count", "time_window"},
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dependencies = {
@@ -160,6 +161,9 @@ function _M.access(conf, ctx)
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local lim, err = core.lrucache.plugin_ctx(lrucache, ctx, conf.policy, create_limit_obj, conf)
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if not lim then
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core.log.error("failed to fetch limit.count object: ", err)
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if conf.allow_degradation then
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return
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end
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return 500
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end
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@@ -174,6 +178,9 @@ function _M.access(conf, ctx)
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end
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core.log.error("failed to limit req: ", err)
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if conf.allow_degradation then
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return
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end
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return 500, {error_msg = "failed to limit count: " .. err}
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end
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‎apisix/plugins/limit-count/limit-count-redis-cluster.lua‎

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Original file line numberDiff line numberDiff line change
@@ -74,8 +74,11 @@ function _M.new(plugin_name, limit, window, conf)
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end
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local self = {
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limit = limit, window = window, conf = conf,
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plugin_name = plugin_name, red_cli =red_cli
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limit = limit,
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window = window,
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conf = conf,
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plugin_name = plugin_name,
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red_cli = red_cli,
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}
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return setmetatable(self, mt)

‎apisix/plugins/limit-count/limit-count-redis.lua‎

Lines changed: 6 additions & 2 deletions
Original file line numberDiff line numberDiff line change
@@ -41,8 +41,12 @@ local script = [=[
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function _M.new(plugin_name, limit, window, conf)
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assert(limit > 0 and window > 0)
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local self = {limit = limit, window = window, conf = conf,
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plugin_name = plugin_name}
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local self = {
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limit = limit,
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window = window,
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conf = conf,
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plugin_name = plugin_name,
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}
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return setmetatable(self, mt)
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end
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‎apisix/plugins/limit-req.lua‎

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Original file line numberDiff line numberDiff line change
@@ -39,6 +39,7 @@ local schema = {
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nodelay = {
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type = "boolean", default = false
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},
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allow_degradation = {type = "boolean", default = false}
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},
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required = {"rate", "burst", "key"}
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}
@@ -73,6 +74,9 @@ function _M.access(conf, ctx)
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create_limit_obj, conf)
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if not lim then
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core.log.error("failed to instantiate a resty.limit.req object: ", err)
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if conf.allow_degradation then
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return
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end
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return 500
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end
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@@ -96,6 +100,9 @@ function _M.access(conf, ctx)
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end
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core.log.error("failed to limit req: ", err)
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if conf.allow_degradation then
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return
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end
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return 500
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end
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‎docs/en/latest/plugins/limit-conn.md‎

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@@ -43,6 +43,7 @@ Limiting request concurrency plugin.
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| only_use_default_delay | boolean | optional | false | [true,false] | enable the strict mode of the latency seconds. If you set this option to `true`, it will run strictly according to the latency seconds you set without additional calculation logic. |
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| key | object | required | | ["remote_addr", "server_addr", "http_x_real_ip", "http_x_forwarded_for", "consumer_name"] | to limit the concurrency level. <br />For example, one can use the host name (or server zone) as the key so that we limit concurrency per host name. Otherwise, we can also use the client address as the key so that we can avoid a single client from flooding our service with too many parallel connections or requests. <br /> 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). |
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| rejected_code | string | optional | 503 | [200,...,599] | returned when the request exceeds `conn` + `burst` will be rejected. |
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| allow_degradation | boolean | optional | false | | Whether to enable plugin degradation when the limit-conn function is temporarily unavailable. Allow requests to continue when the value is set to true, default false. |
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**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.**
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‎docs/en/latest/plugins/limit-count.md‎

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Original file line numberDiff line numberDiff line change
@@ -42,6 +42,7 @@ Limit request rate by a fixed number of requests in a given time window.
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| key | string | optional | "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. <br /> 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". |
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| rejected_code | integer | optional | 503 | [200,...,599] | The HTTP status code returned when the request exceeds the threshold is rejected, default 503. |
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| policy | string | optional | "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. |
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| allow_degradation | boolean | optional | false | | Whether 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. |
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| redis_host | string | required for `redis` | | | When using the `redis` policy, this property specifies the address of the Redis server. |
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| redis_port | integer | optional | 6379 | [1,...] | When using the `redis` policy, this property specifies the port of the Redis server. |
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| redis_password | string | optional | | | When using the `redis` policy, this property specifies the password of the Redis server. |

‎docs/en/latest/plugins/limit-req.md‎

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Original file line numberDiff line numberDiff line change
@@ -43,6 +43,7 @@ limit request rate using the "leaky bucket" method.
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| key | string | required | | ["remote_addr", "server_addr", "http_x_real_ip", "http_x_forwarded_for", "consumer_name"] | the user specified key to limit the rate, 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). |
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| rejected_code | integer | optional | 503 | [200,...,599] | The HTTP status code returned when the request exceeds the threshold is rejected. |
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| nodelay | boolean | optional | false | | If nodelay flag is true, bursted requests will not get delayed |
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| allow_degradation | boolean | optional | false | | Whether to enable plugin degradation when the limit-req function is temporarily unavailable. Allow requests to continue when the value is set to true, default false. |
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**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.**
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‎docs/zh/latest/plugins/limit-conn.md‎

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Original file line numberDiff line numberDiff line change
@@ -33,6 +33,7 @@ title: limit-conn
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| only_use_default_delay | boolean | optional | false | [true,false] | 延迟时间的严格模式。 如果设置为`true`的话，将会严格按照设置的时间来进行延迟 |
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| key | object | required | | ["remote_addr", "server_addr", "http_x_real_ip", "http_x_forwarded_for", "consumer_name"] | 用户指定的限制并发级别的关键字，可以是客户端 IP 或服务端 IP。<br />例如，可以使用主机名（或服务器区域）作为关键字，以便限制每个主机名的并发性。 否则，我们也可以使用客户端地址作为关键字，这样我们就可以避免单个客户端用太多的并行连接或请求淹没我们的服务。 <br />当前接受的 key 有："remote_addr"（客户端 IP 地址）, "server_addr"（服务端 IP 地址）, 请求头中的"X-Forwarded-For" 或 "X-Real-IP", "consumer_name"（consumer 的 username）。 |
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| rejected_code | string | optional | 503 | [200,...,599] | 当请求超过 `conn` + `burst` 这个阈值时，返回的 HTTP 状态码 |
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| allow_degradation | boolean | 可选 | false | | 当插件功能临时不可用时是否允许请求继续。当值设置为 true 时则自动允许请求继续，默认值是 false。|
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**注：key 是可以被用户自定义的，只需要修改插件的一行代码即可完成。并没有在插件中放开是处于安全的考虑。**
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