Merge pull request #205 from porcupie/master

Add MesosDnsId field to Marathon App struct

README.md

@@ -135,6 +135,32 @@ The default template shipped with Bamboo is aware of `BAMBOO_TCP_PORT`. When thi
 
 In this example, both `BAMBOO_TCP_PORT` and `MY_CUSTOM_ENV` can be accessed in HAProxy template. This enables flexible template customization depending on your preferences.
 
+#### Default Haproxy Template ACL
+
+The default acl rule in the `haproxy_template.cfg` uses the full
+marathon app id, which may include slash-separated groups.
+
+```
+        # This is the default proxy criteria
+        acl {{ $app.EscapedId }}-aclrule path_beg -i {{ $app.Id }}
+```
+
+For example if your app is named "/mygroup/appname", your default acl
+will be `path_beg -i /mygroup/appname`.  This can always be changed
+using the bamboo web UI.
+
+There is also a DNS friendly version of your marathon app Id which can
+be used instead of the slash-separated one.  `MesosDnsId` includes the
+groups as hyphenated suffixes.  For example, if your appname is
+"/another/group/app" then the `MesosDnsId` will be "app-group-another".
+
+You can edit the `haproxy_template.cfg` and use the DNS friendly name
+for your default ACL instead.
+
+```
+    acl {{ $app.EscapedId }}-aclrule hdr_dom(host) -i {{ $app.MesosDnsId }}
+```
+
 ### Environment Variables
 
 Configuration in the `production.json` file can be overridden with environment variables below. This is generally useful when you are building a Docker image for Bamboo and HAProxy. If they are not specified then the values from the configuration file will be used.

config/haproxy_template.cfg

@@ -45,6 +45,8 @@ frontend http-in
 
         # This is the default proxy criteria
         acl {{ $app.EscapedId }}-aclrule path_beg -i {{ $app.Id }}
+        # another possible default using DNS-friendly MesosDnsId:
+        #acl {{ $app.EscapedId }}-aclrule hdr_dom(host) -i {{ $app.MesosDnsId }}
         use_backend {{ $app.EscapedId }}-cluster if {{ $app.EscapedId }}-aclrule
         {{ end }} {{ end }}
 

services/marathon/marathon.go

@@ -29,6 +29,7 @@ type HealthCheck struct {
 // An app may have multiple processes
 type App struct {
 	Id              string
+	MesosDnsId      string
 	EscapedId       string
 	HealthCheckPath string
 	HealthChecks    []HealthCheck
@@ -196,6 +197,7 @@ func createApps(tasksById map[string]marathonTaskList, marathonApps map[string]m
 		// build App from marathonApp
 		app := App{
 			Id:              appPath,
+			MesosDnsId:      getMesosDnsId(appPath),
 			EscapedId:       strings.Replace(appId, "/", "::", -1),
 			HealthCheckPath: parseHealthCheckPath(mApp.HealthChecks),
 			Env:             mApp.Env,
@@ -236,6 +238,19 @@ func createApps(tasksById map[string]marathonTaskList, marathonApps map[string]m
 	return apps
 }
 
+func getMesosDnsId(appPath string) string {
+	// split up groups and recombine for how mesos-dns/consul/etc use service name
+	//   "/nested/group/app" -> "app-group-nested"
+	groups := strings.Split(appPath, "/")
+	reverseGroups := []string{}
+	for i := len(groups) - 1; i >= 0; i-- {
+		if groups[i] != "" {
+			reverseGroups = append(reverseGroups, groups[i])
+		}
+	}
+	return strings.Join(reverseGroups, "-")
+}
+
 func parseHealthCheckPath(checks []marathonHealthCheck) string {
 	for _, check := range checks {
 		if check.Protocol != "HTTP" {

services/marathon/marathon_test.go

@@ -5,6 +5,26 @@ import (
 	"testing"
 )
 
+func TestGetMesosDnsId_Simple(t *testing.T) {
+	Convey("#getMesosDnsId", t, func() {
+		Convey("should return simple appname", func() {
+			So(getMesosDnsId("appname"), ShouldEqual, "appname")
+		})
+
+		Convey("should return simple appname if slash prefixed", func() {
+			So(getMesosDnsId("/appname"), ShouldEqual, "appname")
+		})
+
+		Convey("should return groups reverse-added to appname", func() {
+			So(getMesosDnsId("/group/appname"), ShouldEqual, "appname-group")
+		})
+
+		Convey("should return groups reverse-added to appname but no blanks", func() {
+			So(getMesosDnsId("//group/again//appname/"), ShouldEqual, "appname-again-group")
+		})
+	})
+}
+
 func TestParseHealthCheckPathTCP(t *testing.T) {
 	Convey("#parseHealthCheckPath", t, func() {
 		checks := []marathonHealthCheck{