Add VirtualServer custom template support

docs-web/configuration/global-configuration/configmap-resource.md

@@ -382,6 +382,10 @@ See the doc about [VirtualServer and VirtualServerRoute resources](/nginx-ingres
      - Sets the NGINX configuration template for an Ingress resource.
      - By default the template is read from the file on the container.
      - `Custom Templates </nginx-ingress-controller/configuration/global-configuration/custom-templates>`_.
+   * - ``virtualserver-template``
+     - Sets the NGINX configuration template for an VirtualServer resource.
+     - By default the template is read from the file on the container.
+     - `Custom Templates </nginx-ingress-controller/configuration/global-configuration/custom-templates>`_.
 ```
 
 ### Modules

docs-web/configuration/global-configuration/custom-templates.md

@@ -1,3 +1,3 @@
 # Custom Templates
 
-The Ingress Controller uses templates to generate NGINX configuration for Ingress resources and the main NGINX configuration file. You can customize the templates and apply them via the ConfigMap. See the [corresponding example](https://github.com/nginxinc/kubernetes-ingress/tree/master/examples/custom-templates).
+The Ingress Controller uses templates to generate NGINX configuration for Ingress resources, VirtualServer resources and the main NGINX configuration file. You can customize the templates and apply them via the ConfigMap. See the [corresponding example](https://github.com/nginxinc/kubernetes-ingress/tree/master/examples/custom-templates).

examples-of-custom-resources/custom-templates/README.md

@@ -0,0 +1,3 @@
+# Custom Templates
+
+The Ingress Controller uses templates to generate NGINX configuration for VirtualServer resources and the main NGINX configuration file. You can customize the templates and apply them via the ConfigMap. See the [corresponding example](../../examples/custom-templates/README.md).

examples/custom-templates/README.md

@@ -1,10 +1,11 @@
 # Custom Templates
 
-The Ingress controller allows you to customize your templates through a [ConfigMap](https://docs.nginx.com/nginx-ingress-controller/configuration/global-configuration/configmap-resource/) via the following keys:
+The Ingress controller allows you to customize your templates through a [ConfigMap](https://docs.nginx.com/nginx-ingress-controller/configuration/global-configuration/configmap-resource/#snippets-and-custom-templates) via the following keys:
 * `main-template` - Sets the main NGINX configuration template.
 * `ingress-template` - Sets the Ingress NGINX configuration template for an Ingress resource.
+* `virtualserver-template` - Sets the NGINX configuration template for an VirtualServer resource.
 
-## Example
+## Ingress Example
 ```yaml
 kind: ConfigMap
 apiVersion: v1
@@ -13,7 +14,6 @@ metadata:
   namespace: nginx-ingress
 data:
   main-template: |
-    user  nginx;
     worker_processes  {{.WorkerProcesses}};
     ...
         include /etc/nginx/conf.d/*.conf;
@@ -25,9 +25,32 @@ data:
     ...
     }{{end}}
 ```
+
+## VirtualServer Example
+```yaml
+kind: ConfigMap
+apiVersion: v1
+metadata:
+  name: nginx-config
+  namespace: nginx-ingress
+data:
+  main-template: |
+    worker_processes  {{.WorkerProcesses}};
+    ...
+        include /etc/nginx/conf.d/*.conf;
+    }
+  virtualserver-template: |
+    {{ range $u := .Upstreams }}
+    upstream {{ $u.Name }} {
+      {{ if ne $u.UpstreamZoneSize "0" }}zone {{ $u.Name }} {{ $u.UpstreamZoneSize }};{{ end }}
+    ...
+    }
+    {{ end }}
+```
+
 **Notes:**
 * The templates are truncated for the clarity of the example.
-* The templates for NGINX (the main `nginx.tmpl` and the Ingress `nginx.ingress.tmpl`) and NGINX Plus (the main `nginx-plus.tmpl` and the Ingress `nginx-plus.ingress.tmpl`) are located at [internal/configs/templates](../../internal/configs/version1/).
+* The templates for NGINX (the main `nginx.tmpl` and the Ingress `nginx.ingress.tmpl`) and NGINX Plus (the main `nginx-plus.tmpl` and the Ingress `nginx-plus.ingress.tmpl`) are located at [internal/configs/version1](../../internal/configs/version1/). The VirtualServer templates for NGINX (`nginx.virtualserver.tmpl`) and NGINX Plus (`nginx-plus.virtualserver.tmpl`) are located at [internal/configs/version2](../../internal/configs/version2/).
 
 ## Troubleshooting
 * If a custom template contained within the ConfigMap is invalid on startup, the Ingress controller will fail to start, the error will be reported in the Ingress controller logs.

internal/configs/config_params.go

@@ -84,8 +84,9 @@ type ConfigParams struct {
 	MainServerSSLPreferServerCiphers bool
 	MainServerSSLProtocols           string
 
-	IngressTemplate *string
-	MainTemplate    *string
+	IngressTemplate       *string
+	VirtualServerTemplate *string
+	MainTemplate          *string
 
 	JWTKey      string
 	JWTLoginURL string

internal/configs/configmaps.go

@@ -353,6 +353,10 @@ func ParseConfigMap(cfgm *v1.ConfigMap, nginxPlus bool, hasAppProtect bool) *Con
 		cfgParams.IngressTemplate = &ingressTemplate
 	}
 
+	if virtualServerTemplate, exists := cfgm.Data["virtualserver-template"]; exists {
+		cfgParams.VirtualServerTemplate = &virtualServerTemplate
+	}
+
 	if mainStreamSnippets, exists, err := GetMapKeyAsStringSlice(cfgm.Data, "stream-snippets", cfgm, "\n"); exists {
 		if err != nil {
 			glog.Error(err)

internal/configs/configurator.go

@@ -769,6 +769,13 @@ func (cnf *Configurator) UpdateConfig(cfgParams *ConfigParams, ingExes []*Ingres
 		}
 	}
 
+	if cfgParams.VirtualServerTemplate != nil {
+		err := cnf.templateExecutorV2.UpdateVirtualServerTemplate(cfgParams.VirtualServerTemplate)
+		if err != nil {
+			return allWarnings, fmt.Errorf("Error when parsing the VirtualServer template: %v", err)
+		}
+	}
+
 	mainCfg := GenerateNginxMainConfig(cnf.staticCfgParams, cfgParams)
 	mainCfgContent, err := cnf.templateExecutor.ExecuteMainConfigTemplate(mainCfg)
 	if err != nil {

internal/configs/version2/template_executor.go

@@ -45,6 +45,17 @@ func NewTemplateExecutor(virtualServerTemplatePath string, transportServerTempla
 	}, nil
 }
 
+// UpdateVirtualServerTemplate updates the VirtualServer template.
+func (te *TemplateExecutor) UpdateVirtualServerTemplate(templateString *string) error {
+	newTemplate, err := template.New("virtualServerTemplate").Parse(*templateString)
+	if err != nil {
+		return err
+	}
+	te.virtualServerTemplate = newTemplate
+
+	return nil
+}
+
 // ExecuteVirtualServerTemplate generates the content of an NGINX configuration file for a VirtualServer resource.
 func (te *TemplateExecutor) ExecuteVirtualServerTemplate(cfg *VirtualServerConfig) ([]byte, error) {
 	var configBuffer bytes.Buffer