Merge pull request #29 from notmaxx/feature_locations

feat(router): support locations in router

README.md

@@ -288,6 +288,8 @@ _Note that Kubernetes annotation maps are all of Go type `map[string]string`.  A
 | <a name="app-nginx-proxy-buffers-number"></a>routable application | service | [router.deis.io/nginx.proxyBuffers.number](#app-nginx-proxy-buffers-number) | `"8"` | `number` argument to the nginx `proxy_buffers` directive. This can be used to override the same option set globally on the router. |
 | <a name="app-nginx-proxy-buffers-size"></a>routable application | service | [router.deis.io/nginx.proxyBuffers.size](#app-nginx-proxy-buffers-size) | `"4k"` | `size` argument to the nginx `proxy_buffers` directive expressed in bytes (no suffix), kilobytes (suffixes `k` and `K`), or megabytes (suffixes `m` and `M`). This can be used to override the same option set globally on the router. |
 | <a name="app-nginx-proxy-buffers-busy-size"></a>routable application | service | [router.deis.io/nginx.proxyBuffers.busySize](#app-nginx-proxy-buffers-busy-size) | `"8k"` | nginx `proxy_busy_buffers_size` expressed in bytes (no suffix), kilobytes (suffixes `k` and `K`), or megabytes (suffixes `m` and `M`). This can be used to override the same option set globally on the router. |
+|<a name="app-proxy-locations"></a>routable application | service | [router.deis.io/proxyLocations](#app-proxy-locations) | N/A | A list of locations of this service to plug-in into another service determined by `router.deis.io/proxyDomain`  (see example below)  |
+|<a name="app-proxy-domain"></a>routable application | service | [router.deis.io/proxyDomain](#app-proxy-domain) | N/A | A reference to another service to plug-in `router.deis.io/proxyLocations` to (see example below) |
 
 #### Annotations by example
 
@@ -337,6 +339,40 @@ metadata:
 # ...
 ```
 
+##### proxy locations:
+
+Service of the application where we want `/webhooks` path to be handled by another service
+```
+apiVersion: v1
+kind: Service
+metadata:
+  name: app_with_overwritten_webhooks_location
+  labels:
+    router.deis.io/routable: "true"
+  namespace: router-examples
+  # ...
+  annotations:
+    router.deis.io/domains: app_with_overwritten_webhooks_location
+# ...
+```
+
+Service of the application which should handle `/webhooks` path of the app above
+```
+apiVersion: v1
+kind: Service
+metadata:
+  name: app_webhooks_location_handler
+  labels:
+    router.deis.io/routable: "true"
+  namespace: router-examples
+  # ...
+  annotations:
+    ...
+    router.deis.io/proxyDomain=app_with_overwritten_webhooks_location
+    router.deis.io/proxyLocations=/webhooks
+# ...
+```
+
 ### <a name="ssl"></a>SSL
 
 Router has support for HTTPS with the ability to perform SSL termination using certificates supplied via Kubernetes secrets.  Just as router utilizes the Kubernetes API to discover routable services, router also uses the API to discover cert-bearing secrets.  This allows the router to dynamically refresh and reload configuration whenever such a certificate is added, updated, or removed.  There is never a need to explicitly restart the router.

model/model.go

@@ -3,6 +3,7 @@ package model
 import (
 	"bytes"
 	"encoding/gob"
+	goerrors "errors"
 	"fmt"
 	"log"
 	"strings"
@@ -150,6 +151,14 @@ type AppConfig struct {
 	Maintenance    bool            `key:"maintenance" constraint:"(?i)^(true|false)$"`
 	SSLConfig      *SSLConfig      `key:"ssl"`
 	Nginx          *NginxAppConfig `key:"nginx"`
+	ProxyLocations []string        `key:"proxyLocations"`
+	ProxyDomain    string          `key:"proxyDomain"`
+	Locations      []*Location
+}
+
+type Location struct {
+	App  *AppConfig
+	Path string
 }
 
 func newAppConfig(routerConfig *RouterConfig) (*AppConfig, error) {
@@ -391,6 +400,11 @@ func build(kubeClient *kubernetes.Clientset, routerDeployment *v1beta1ext.Deploy
 			routerConfig.AppConfigs = append(routerConfig.AppConfigs, appConfig)
 		}
 	}
+	err = linkLocations(routerConfig.AppConfigs)
+	if err != nil {
+		return nil, err
+	}
+	addRootLocations(routerConfig.AppConfigs)
 	if builderService != nil {
 		builderConfig, err := buildBuilderConfig(builderService)
 		if err != nil {
@@ -403,6 +417,41 @@ func build(kubeClient *kubernetes.Clientset, routerDeployment *v1beta1ext.Deploy
 	return routerConfig, nil
 }
 
+func appByDomain(appConfigs []*AppConfig, domain string) *AppConfig {
+	for _, app := range appConfigs {
+		for _, appDomain := range app.Domains {
+			if domain == appDomain {
+				return app
+			}
+		}
+	}
+	return nil
+}
+
+func linkLocations(appConfigs []*AppConfig) error {
+	for _, app := range appConfigs {
+		if app.ProxyDomain != "" && len(app.ProxyLocations) > 0 {
+			targetApp := appByDomain(appConfigs, app.ProxyDomain)
+			if targetApp == nil {
+				return goerrors.New(fmt.Sprintf("Can't find ProxyDomain '%s' in any application", app.ProxyDomain))
+			}
+
+			for _, loc := range app.ProxyLocations {
+				location := &Location{App: app, Path: loc}
+				targetApp.Locations = append(targetApp.Locations, location)
+			}
+		}
+	}
+	return nil
+}
+
+func addRootLocations(appConfigs []*AppConfig) {
+	for _, app := range appConfigs {
+		rootLocation := &Location{App: app, Path: "/"}
+		app.Locations = append(app.Locations, rootLocation)
+	}
+}
+
 func buildRouterConfig(routerDeployment *v1beta1.Deployment, platformCertSecret *v1.Secret, dhParamSecret *v1.Secret) (*RouterConfig, error) {
 	routerConfig, err := newRouterConfig()
 	if err != nil {
@@ -449,6 +498,7 @@ func buildAppConfig(kubeClient *kubernetes.Clientset, service v1.Service, router
 	if err != nil {
 		return nil, err
 	}
+
 	// If no domains are found, we don't have the information we need to build routes
 	// to this application.  Abort.
 	if len(appConfig.Domains) == 0 {

nginx/config.go

@@ -270,41 +270,44 @@ 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 {{ if $appConfig.Nginx.ProxyBuffersConfig.Enabled }}on{{ else }}off{{ end }};
-			proxy_buffer_size {{ $appConfig.Nginx.ProxyBuffersConfig.Size }};
-			proxy_buffers {{ $appConfig.Nginx.ProxyBuffersConfig.Number }} {{ $appConfig.Nginx.ProxyBuffersConfig.Size }};
-			proxy_busy_buffers_size {{ $appConfig.Nginx.ProxyBuffersConfig.BusySize }};
-			proxy_set_header Host $host;
-			proxy_set_header X-Forwarded-For $remote_addr;
-			proxy_set_header X-Forwarded-Proto $access_scheme;
-			proxy_set_header X-Forwarded-Port $forwarded_port;
-			proxy_redirect off;
-			proxy_connect_timeout {{ $appConfig.ConnectTimeout }};
-			proxy_send_timeout {{ $appConfig.TCPTimeout }};
-			proxy_read_timeout {{ $appConfig.TCPTimeout }};
-			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 $enforceSecure $appConfig.SSLConfig.Enforce }}if ($access_scheme !~* "^https|wss$") {
-				return 301 $uri_scheme://$host$request_uri;
-			}{{ end }}
-
-			{{ if $hstsConfig.Enabled }}add_header Strict-Transport-Security $sts always;{{ end }}
+		{{range $location := $appConfig.Locations}}
+			location {{ $location.Path }} {
+				{{ if $routerConfig.RequestIDs }}
+				add_header X-Request-Id $request_id always;
+				add_header X-Correlation-Id $correlation_id always;
+				{{end}}
+
+				{{ if $location.App.Maintenance }}return 503;{{ else if $location.App.Available }}
+				proxy_buffering {{ if $location.App.Nginx.ProxyBuffersConfig.Enabled }}on{{ else }}off{{ end }};
+				proxy_buffer_size {{ $location.App.Nginx.ProxyBuffersConfig.Size }};
+				proxy_buffers {{ $location.App.Nginx.ProxyBuffersConfig.Number }} {{ $location.App.Nginx.ProxyBuffersConfig.Size }};
+				proxy_busy_buffers_size {{ $location.App.Nginx.ProxyBuffersConfig.BusySize }};
+				proxy_set_header Host $host;
+				proxy_set_header X-Forwarded-For $remote_addr;
+				proxy_set_header X-Forwarded-Proto $access_scheme;
+				proxy_set_header X-Forwarded-Port $forwarded_port;
+				proxy_redirect off;
+				proxy_connect_timeout {{ $location.App.ConnectTimeout }};
+				proxy_send_timeout {{ $location.App.TCPTimeout }};
+				proxy_read_timeout {{ $location.App.TCPTimeout }};
+				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 $enforceSecure $location.App.SSLConfig.Enforce }}if ($access_scheme !~* "^https|wss$") {
+					return 301 $uri_scheme://$host$request_uri;
+				}{{ end }}
+
+				{{ if $hstsConfig.Enabled }}add_header Strict-Transport-Security $sts always;{{ end }}
+
+				proxy_pass http://{{$location.App.ServiceIP}}:80;{{ else }}return 503;{{ end }}
+			}
+		{{end}}
 
-			proxy_pass http://{{$appConfig.ServiceIP}}:80;{{ else }}return 503;{{ end }}
-		}
 		{{ if $appConfig.Maintenance }}error_page 503 @maintenance;
 			location @maintenance {
 					root /;