This patch extens Kudu to use the given app subdomains instead random ports with localhost for site bindings.

kudu_with_subdomain.patch

 Kudu.SiteManagement/SiteManager.cs | 31 ++++++++++++++++++-------------
 1 file changed, 18 insertions(+), 13 deletions(-)

diff --git a/Kudu.SiteManagement/SiteManager.cs b/Kudu.SiteManagement/SiteManager.cs
index 43a6012..87b466d 100644
--- a/Kudu.SiteManagement/SiteManager.cs
+++ b/Kudu.SiteManagement/SiteManager.cs
@@ -6,12 +6,15 @@
 using System.Net.NetworkInformation;
 using System.Threading;
 using Kudu.Core.Infrastructure;
+using Microsoft.Web.Administration;
 using IIS = Microsoft.Web.Administration;
 
 namespace Kudu.SiteManagement
 {
     public class SiteManager : ISiteManager
     {
+        const string BaseHost = "kudu.local";
+
         private static Random portNumberGenRnd = new Random((int)DateTime.Now.Ticks);
 
         private readonly IPathResolver _pathResolver;
@@ -94,7 +97,7 @@ public Site CreateSite(string applicationName)
             {
                 // Create the service site for this site
                 string serviceSiteName = GetServiceSite(applicationName);
-                int serviceSitePort = CreateSite(iis, applicationName, serviceSiteName, _pathResolver.ServiceSitePath);
+                string serviceUrl = CreateSite(iis, applicationName, serviceSiteName, _pathResolver.ServiceSitePath);
 
                 // Create the main site
                 string siteName = GetLiveSite(applicationName);
@@ -115,7 +118,7 @@ public Site CreateSite(string applicationName)
 </body> 
 </html>");
 
-                int sitePort = CreateSite(iis, applicationName, siteName, webRoot);
+                string siteUrl = CreateSite(iis, applicationName, siteName, webRoot, 80);
 
                 // Map a path called app to the site root under the service site
                 MapServiceSitePath(iis, applicationName, Constants.MappedLiveSite, siteRoot);
@@ -129,8 +132,8 @@ public Site CreateSite(string applicationName)
 
                 return new Site
                 {
-                    ServiceUrl = String.Format("http://localhost:{0}/", serviceSitePort),
-                    SiteUrl = String.Format("http://localhost:{0}/", sitePort),
+                    ServiceUrl = serviceUrl,
+                    SiteUrl = siteUrl,
                 };
             }
             catch
@@ -152,7 +155,7 @@ public bool TryCreateDeveloperSite(string applicationName, out string siteUrl)
                 // Get the path to the dev site
                 string siteRoot = _pathResolver.GetDeveloperApplicationPath(applicationName);
                 string webRoot = Path.Combine(siteRoot, Constants.WebRoot);
-                int sitePort = CreateSite(iis, applicationName, devSiteName, webRoot);
+                siteUrl = CreateSite(iis, applicationName, devSiteName, webRoot);
 
                 // Ensure the directory is created
                 FileSystemHelpers.EnsureDirectory(webRoot);
@@ -162,12 +165,11 @@ public bool TryCreateDeveloperSite(string applicationName, out string siteUrl)
 
                 iis.CommitChanges();
 
-
-                siteUrl = String.Format("http://localhost:{0}/", sitePort);
                 return true;
             }
 
-            siteUrl = String.Format("http://localhost:{0}/", site.Bindings[0].EndPoint.Port);
+            var host = applicationName + "." + BaseHost;
+            siteUrl = String.Format("http://{0}:{1}/", host, site.Bindings[0].EndPoint.Port);
             return false;
         }
 
@@ -390,12 +392,15 @@ private bool IsAvailable(int port, IIS.ServerManager iis)
             return true;
         }
 
-        private int CreateSite(IIS.ServerManager iis, string applicationName, string siteName, string siteRoot)
+        private string CreateSite(ServerManager iis, string applicationName, string siteName, string siteRoot, int sitePort = -1)
         {
             var pool = EnsureAppPool(iis, applicationName);
 
-            int sitePort = GetRandomPort(iis);
-            var site = iis.Sites.Add(siteName, siteRoot, sitePort);
+            if(sitePort<=0)
+                sitePort = GetRandomPort(iis);
+
+            var host = applicationName + "." + BaseHost;
+            var site = iis.Sites.Add(siteName, "http", "*:" + sitePort + ":" + host, siteRoot);
             site.ApplicationDefaults.ApplicationPoolName = pool.Name;
 
             if (_traceFailedRequests)
@@ -406,7 +411,7 @@ private int CreateSite(IIS.ServerManager iis, string applicationName, string sit
                 site.TraceFailedRequestsLogging.Directory = path;
             }
 
-            return sitePort;
+            return String.Format("http://{0}:{1}/", host, sitePort);
         }
 
         private void DeleteSite(IIS.ServerManager iis, string siteName, bool deletePhysicalFiles = true)