Merge pull request #719 from adfin/upstream-vhost

POC: Setting upstream vhost for nginx.

controllers/nginx/rootfs/etc/nginx/template/nginx.tmpl

@@ -698,7 +698,13 @@ stream {
             client_body_buffer_size                 {{ $location.ClientBodyBufferSize }};
             {{ end }}
 
+            {{/* By default use vhost as Host to upstream, but allow overrides */}}
+            {{ if not (empty $location.UpstreamVhost) }}
+            proxy_set_header Host                   "{{ $location.UpstreamVhost }}";
+            {{ else }}
             proxy_set_header Host                   $best_http_host;
+            {{ end }}
+
 
             # Pass the extracted client certificate to the backend
             {{ if not (empty $server.CertificateAuth.CAFileName) }}

core/pkg/ingress/annotations/upstreamvhost/main.go

@@ -0,0 +1,42 @@
+/*
+Copyright 2017 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package upstreamvhost
+
+import (
+	extensions "k8s.io/api/extensions/v1beta1"
+
+	"k8s.io/ingress/core/pkg/ingress/annotations/parser"
+)
+
+const (
+	annotation = "ingress.kubernetes.io/upstream-vhost"
+)
+
+type upstreamVhost struct {
+}
+
+// NewParser creates a new upstream VHost annotation parser
+func NewParser() parser.IngressAnnotation {
+	return upstreamVhost{}
+}
+
+// Parse parses the annotations contained in the ingress rule
+// used to indicate if the location/s contains a fragment of
+// configuration to be included inside the paths of the rules
+func (a upstreamVhost) Parse(ing *extensions.Ingress) (interface{}, error) {
+	return parser.GetStringAnnotation(annotation, ing)
+}

core/pkg/ingress/controller/annotations.go

@@ -39,6 +39,7 @@ import (
 	"k8s.io/ingress/core/pkg/ingress/annotations/sessionaffinity"
 	"k8s.io/ingress/core/pkg/ingress/annotations/snippet"
 	"k8s.io/ingress/core/pkg/ingress/annotations/sslpassthrough"
+	"k8s.io/ingress/core/pkg/ingress/annotations/upstreamvhost"
 	"k8s.io/ingress/core/pkg/ingress/errors"
 	"k8s.io/ingress/core/pkg/ingress/resolver"
 )
@@ -78,6 +79,7 @@ func newAnnotationExtractor(cfg extractorConfig) annotationExtractor {
 			"Alias":                alias.NewParser(),
 			"ClientBodyBufferSize": clientbodybuffersize.NewParser(),
 			"DefaultBackend":       defaultbackend.NewParser(cfg),
+			"UpstreamVhost":        upstreamvhost.NewParser(),
 		},
 	}
 }

core/pkg/ingress/types.go

@@ -273,6 +273,10 @@ type Location struct {
 	Service *api.Service `json:"service,omitempty"`
 	// Port describes to which port from the service
 	Port intstr.IntOrString `json:"port"`
+	// Overwrite the Host header passed into the backend. Defaults to
+	// vhost of the incoming request.
+	// +optional
+	UpstreamVhost string `json:"upstream-vhost"`
 	// BasicDigestAuth returns authentication configuration for
 	// an Ingress rule.
 	// +optional