Upstream keepalive time (#8319)

* nginx 1.19.10 keepalive_time parameter

* nginx v1.19.10 base image

* keepalive_time documentation

* base image

* restore base image

* e2e test

* replace default value in test

docs/user-guide/nginx-configuration/configmap.md

@@ -111,6 +111,7 @@ The following table shows a configuration option's name, type, and the default v
 |[variables-hash-bucket-size](#variables-hash-bucket-size)|int|128|
 |[variables-hash-max-size](#variables-hash-max-size)|int|2048|
 |[upstream-keepalive-connections](#upstream-keepalive-connections)|int|320|
+|[upstream-keepalive-time](#upstream-keepalive-time)|string|"1h"|
 |[upstream-keepalive-timeout](#upstream-keepalive-timeout)|int|60|
 |[upstream-keepalive-requests](#upstream-keepalive-requests)|int|10000|
 |[limit-conn-zone-variable](#limit-conn-zone-variable)|string|"$binary_remote_addr"|
@@ -223,13 +224,13 @@ Enables the return of the header Server from the backend instead of the generic
 
 Enables Ingress to parse and add *-snippet annotations/directives created by the user. _**default:**_ `true`
 
-Warning: We recommend enabling this option only if you TRUST users with permission to create Ingress objects, as this 
+Warning: We recommend enabling this option only if you TRUST users with permission to create Ingress objects, as this
 may allow a user to add restricted configurations to the final nginx.conf file
 
 ## annotation-value-word-blocklist
 
-Contains a comma-separated value of chars/words that are well known of being used to abuse Ingress configuration 
-and must be blocked. Related to [CVE-2021-25742](https://github.com/kubernetes/ingress-nginx/issues/7837) 
+Contains a comma-separated value of chars/words that are well known of being used to abuse Ingress configuration
+and must be blocked. Related to [CVE-2021-25742](https://github.com/kubernetes/ingress-nginx/issues/7837)
 
 When an annotation is detected with a value that matches one of the blocked bad words, the whole Ingress won't be configured.
 
@@ -769,6 +770,14 @@ _References:_
 [https://nginx.org/en/docs/http/ngx_http_upstream_module.html#keepalive](https://nginx.org/en/docs/http/ngx_http_upstream_module.html#keepalive)
 
 
+## upstream-keepalive-time
+
+Sets the maximum time during which requests can be processed through one keepalive connection.
+ _**default:**_ "1h"
+
+_References:_
+[http://nginx.org/en/docs/http/ngx_http_upstream_module.html#keepalive_time](http://nginx.org/en/docs/http/ngx_http_upstream_module.html#keepalive_time)
+
 ## upstream-keepalive-timeout
 
 Sets a timeout during which an idle keepalive connection to an upstream server will stay open.
@@ -1258,7 +1267,7 @@ Configure `memcached` client for [Global Rate Limiting](https://github.com/kuber
 * `global-rate-limit-memcached-host`: IP/FQDN of memcached server to use. Required to enable Global Rate Limiting.
 * `global-rate-limit-memcached-port`: port of memcached server to use. Defaults default memcached port of `11211`.
 * `global-rate-limit-memcached-connect-timeout`: configure timeout for connect, send and receive operations. Unit is millisecond. Defaults to 50ms.
-* `global-rate-limit-memcached-max-idle-timeout`: configure timeout for cleaning idle connections. Unit is millisecond. Defaults to 50ms. 
+* `global-rate-limit-memcached-max-idle-timeout`: configure timeout for cleaning idle connections. Unit is millisecond. Defaults to 50ms.
 * `global-rate-limit-memcached-pool-size`: configure number of max connections to keep alive. Make sure your `memcached` server can handle
 `global-rate-limit-memcached-pool-size * worker-processes * <number of ingress-nginx replicas>` simultaneous connections.
 

internal/ingress/controller/config/config.go

@@ -468,6 +468,10 @@ type Configuration struct {
 	// http://nginx.org/en/docs/http/ngx_http_upstream_module.html#keepalive
 	UpstreamKeepaliveConnections int `json:"upstream-keepalive-connections,omitempty"`
 
+	// Sets the maximum time during which requests can be processed through one keepalive connection
+	// https://nginx.org/en/docs/http/ngx_http_upstream_module.html#keepalive_time
+	UpstreamKeepaliveTime string `json:"upstream-keepalive-time,omitempty"`
+
 	// Sets a timeout during which an idle keepalive connection to an upstream server will stay open.
 	// http://nginx.org/en/docs/http/ngx_http_upstream_module.html#keepalive_timeout
 	UpstreamKeepaliveTimeout int `json:"upstream-keepalive-timeout,omitempty"`
@@ -892,6 +896,7 @@ func NewDefault() Configuration {
 			ServiceUpstream:          false,
 		},
 		UpstreamKeepaliveConnections:           320,
+		UpstreamKeepaliveTime:                  "1h",
 		UpstreamKeepaliveTimeout:               60,
 		UpstreamKeepaliveRequests:              10000,
 		LimitConnZoneVariable:                  defaultLimitConnZoneVariable,

rootfs/etc/nginx/template/nginx.tmpl

@@ -156,7 +156,7 @@ http {
     {{ else }}
     modsecurity_rules_file /etc/nginx/modsecurity/modsecurity.conf;
     {{ end }}
-    
+
     {{ if $all.Cfg.EnableOWASPCoreRules }}
     modsecurity_rules_file /etc/nginx/owasp-modsecurity-crs/nginx-modsecurity.conf;
     {{ end }}
@@ -508,7 +508,7 @@ http {
 
         {{ if (gt $cfg.UpstreamKeepaliveConnections 0) }}
         keepalive {{ $cfg.UpstreamKeepaliveConnections }};
-
+        keepalive_time {{ $cfg.UpstreamKeepaliveTime }};
         keepalive_timeout  {{ $cfg.UpstreamKeepaliveTimeout }}s;
         keepalive_requests {{ $cfg.UpstreamKeepaliveRequests }};
         {{ end }}

test/e2e/settings/keep-alive.go

@@ -74,6 +74,15 @@ var _ = framework.DescribeSetting("keep-alive keep-alive-requests", func() {
 			})
 		})
 
+		ginkgo.It("should set keepalive time to upstream server", func() {
+			f.UpdateNginxConfigMapData("upstream-keepalive-time", "75s")
+
+			f.WaitForNginxConfiguration(func(server string) bool {
+				match, _ := regexp.MatchString(`upstream\supstream_balancer\s\{[\s\S]*keepalive_time\s*75s;`, server)
+				return match
+			})
+		})
+
 		ginkgo.It("should set the request count to upstream server through one keep alive connection", func() {
 			f.UpdateNginxConfigMapData("upstream-keepalive-requests", "200")