Split documentation

docs/user-guide/custom-template.md

@@ -0,0 +1,54 @@
+# Custom NGINX template
+
+The NGINX template is located in the file `/etc/nginx/template/nginx.tmpl`.
+
+Using a [Volume](https://kubernetes.io/docs/concepts/storage/volumes/) it is possible to use a custom template. 
+This includes using a [Configmap](https://kubernetes.io/docs/concepts/storage/volumes/#example-pod-with-a-secret-a-downward-api-and-a-configmap) as source of the template
+
+```yaml
+        volumeMounts:
+          - mountPath: /etc/nginx/template
+            name: nginx-template-volume
+            readOnly: true
+      volumes:
+        - name: nginx-template-volume
+          configMap:
+            name: nginx-template
+            items:
+            - key: nginx.tmpl
+              path: nginx.tmpl
+```
+
+**Please note the template is tied to the Go code. Do not change names in the variable `$cfg`.**
+
+For more information about the template syntax please check the [Go template package](https://golang.org/pkg/text/template/).
+In addition to the built-in functions provided by the Go package the following functions are also available:
+
+- empty: returns true if the specified parameter (string) is empty
+- contains: [strings.Contains](https://golang.org/pkg/strings/#Contains)
+- hasPrefix: [strings.HasPrefix](https://golang.org/pkg/strings/#HasPrefix)
+- hasSuffix: [strings.HasSuffix](https://golang.org/pkg/strings/#HasSuffix)
+- toUpper: [strings.ToUpper](https://golang.org/pkg/strings/#ToUpper)
+- toLower: [strings.ToLower](https://golang.org/pkg/strings/#ToLower)
+- buildLocation: helps to build the NGINX Location section in each server
+- buildProxyPass: builds the reverse proxy configuration
+- buildRateLimit: helps to build a limit zone inside a location if contains a rate limit annotation
+
+TODO:
+
+- buildAuthLocation:
+- buildAuthResponseHeaders:
+- buildResolvers:
+- buildLogFormatUpstream:
+- buildDenyVariable:
+- buildUpstreamName:
+- buildForwardedFor:
+- buildAuthSignURL:
+- buildNextUpstream:
+- filterRateLimits:
+- formatIP:
+- getenv:
+- getIngressInformation:
+- serverConfig:
+- isLocationAllowed:
+- isValidClientBodyBufferSize: