Add limit-request-status-code option (#2001)

* Add support for limit_req_status

* Add documentation

* Fix comment

Author: aramase

docs/user-guide/configmap.md

@@ -127,6 +127,7 @@ The following table shows a configuration option's name, type, and the default v
 |[limit‑rate‑after](#limit-rate-after)|int|0|
 |[http‑redirect‑code](#http-redirect-code)|int|308|
 |[proxy‑buffering](#proxy-buffering)|string|"off"|
+|[limit‑request‑status‑code](#limit-request-status-code)|int|503|
 
 ## add-headers
 
@@ -702,4 +703,8 @@ Why the default code is 308?
 
 ## proxy-buffering
 
-Enables or disables [buffering of responses from the proxied server](http://nginx.org/en/docs/http/ngx_http_proxy_module.html#proxy_buffering).
+Enables or disables [buffering of responses from the proxied server](http://nginx.org/en/docs/http/ngx_http_proxy_module.html#proxy_buffering).
+
+## limit-request-status-code
+
+Sets the [status code to return in response to rejected requests](http://nginx.org/en/docs/http/ngx_http_limit_req_module.html#limit_req_status).Default: 503

internal/ingress/controller/config/config.go

@@ -467,6 +467,11 @@ type Configuration struct {
 	// server to the client response
 	// Default: empty
 	HideHeaders []string `json:"hide-headers"`
+
+	// LimitReqStatusCode Sets the status code to return in response to rejected requests.
+	// http://nginx.org/en/docs/http/ngx_http_limit_req_module.html#limit_req_status
+	// Default: 503
+	LimitReqStatusCode int `json:"limit-req-status-code"`
 }
 
 // NewDefault returns the default nginx configuration
@@ -560,6 +565,7 @@ func NewDefault() Configuration {
 		JaegerServiceName:            "nginx",
 		JaegerSamplerType:            "const",
 		JaegerSamplerParam:           "1",
+		LimitReqStatusCode:           503,
 	}
 
 	if glog.V(5) {

rootfs/etc/nginx/template/nginx.tmpl

@@ -102,6 +102,8 @@ http {
     underscores_in_headers          {{ if $cfg.EnableUnderscoresInHeaders }}on{{ else }}off{{ end }};
     ignore_invalid_headers          {{ if $cfg.IgnoreInvalidHeaders }}on{{ else }}off{{ end }};
 
+    limit_req_status                {{ $cfg.LimitReqStatusCode }};
+
     {{ if $cfg.EnableOpentracing }}
     opentracing on;
     {{ end }}