feat(nginx): Allow sending nginx X-Request-Id and X-Correlation-Id headers.

Author: Rob Holland

model/model.go

@@ -49,6 +49,7 @@ type RouterConfig struct {
 	EnforceWhitelists        bool        `key:"enforceWhitelists" constraint:"(?i)^(true|false)$"`
 	DefaultWhitelist         []string    `key:"defaultWhitelist" constraint:"^((([0-9]|[1-9][0-9]|1[0-9]{2}|2[0-4][0-9]|25[0-5])\\.){3}([0-9]|[1-9][0-9]|1[0-9]{2}|2[0-4][0-9]|25[0-5])(\\/([0-9]|[1-2][0-9]|3[0-2]))?(\\s*,\\s*)?)+$"`
 	WhitelistMode            string      `key:"whitelistMode" constraint:"^(extend|override)$"`
+	RequestIDs               bool        `key:"RequestIDs" constraint:"(?i)^(true|false)$"`
 	SSLConfig                *SSLConfig  `key:"ssl"`
 	AppConfigs               []*AppConfig
 	BuilderConfig            *BuilderConfig
@@ -71,6 +72,7 @@ func newRouterConfig() *RouterConfig {
 		UseProxyProtocol:         false,
 		EnforceWhitelists:        false,
 		WhitelistMode:            "extend",
+		RequestIDs:               false,
 		SSLConfig:                newSSLConfig(),
 		HTTP2Enabled:             true,
 	}

nginx/config.go

@@ -108,6 +108,13 @@ http {
 	}
 	{{ end }}
 
+	{{ if $routerConfig.RequestIDs }}
+		map $http_x_correlation_id $correlation_id {
+			default "$http_x_correlation_id,$request_id";
+			'' $request_id;
+		}
+	{{ end }}
+
 	{{/* Since HSTS headers are not permitted on HTTP requests, 301 redirects to HTTPS resources are also necessary. */}}
 	{{/* This means we force HTTPS if HSTS is enabled. */}}
 	{{ $enforceHTTPS := or $sslConfig.Enforce $hstsConfig.Enabled }}
@@ -188,6 +195,11 @@ http {
 		vhost_traffic_status_filter_by_set_key {{ $appConfig.Name }} application::*;
 
 		location / {
+			{{ if $routerConfig.RequestIDs }}
+			add_header X-Request-Id $request_id always;
+			add_header X-Correlation-Id $correlation_id always;
+			{{end}}
+
 			{{ if $appConfig.Maintenance }}return 503;{{ else if $appConfig.Available }}proxy_buffering off;
 			proxy_set_header Host $host;
 			proxy_set_header X-Forwarded-For $remote_addr;
@@ -200,6 +212,10 @@ http {
 			proxy_http_version 1.1;
 			proxy_set_header Upgrade $http_upgrade;
 			proxy_set_header Connection $connection_upgrade;
+			{{ if $routerConfig.RequestIDs }}
+			proxy_set_header X-Request-Id $request_id;
+			proxy_set_header X-Correlation-Id $correlation_id;
+			{{ end }}
 
 			{{ if or $enforceHTTPS $appConfig.SSLConfig.Enforce }}if ($access_scheme != "https") {
 				return 301 https://$host$request_uri;