Set default ApplicationName and ApplicationBase in ApplicationEnvironment #613

src/Microsoft.AspNetCore.Hosting/WebHostBuilder.cs

@@ -4,6 +4,7 @@
 using System;
 using System.Diagnostics;
 using System.IO;
+using System.Reflection;
 using System.Runtime.Versioning;
 using Microsoft.AspNetCore.Builder;
 using Microsoft.AspNetCore.Hosting.Builder;
@@ -199,10 +200,9 @@ namespace Microsoft.AspNetCore.Hosting
                 if (defaultPlatformServices.Application != null)
                 {
                     var appEnv = defaultPlatformServices.Application;
-                    if (!string.IsNullOrEmpty(_options.ApplicationBasePath))
+                    var applicationBasePath = ResolveApplicationBasePath(_options.ApplicationBasePath, appEnv.ApplicationBasePath);
-                    {
+                    var startupAssemblyName = ResolveStartupAssemblyName() ?? appEnv.ApplicationName;
-                        appEnv = new WrappedApplicationEnvironment(_options.ApplicationBasePath, appEnv);
+                    appEnv = new WrappedApplicationEnvironment(applicationBasePath, startupAssemblyName, defaultPlatformServices.Application);
-                    }
 
                     services.TryAddSingleton(appEnv);
                 }
@@ -221,12 +221,59 @@ namespace Microsoft.AspNetCore.Hosting
             return services;
         }
 
+        private string ResolveApplicationBasePath(string applicationBasePath, string basePath)
+        {
+            if (_startup != null)
+            {
+                var startupAssemblyLocation = _startup.ConfigureDelegate.Target.GetType().GetTypeInfo().Assembly.Location;
+                if (!string.IsNullOrEmpty(startupAssemblyLocation))
+                {
+                    return Path.GetDirectoryName(startupAssemblyLocation);
+                }
+            }
+            else if (_startupType != null)
+            {
+                var startupAssemblyLocation = _startupType.GetTypeInfo().Assembly.Location;
+                if (!string.IsNullOrEmpty(startupAssemblyLocation)) 
+                {
+                    return Path.GetDirectoryName(startupAssemblyLocation);
+                }
+            }
+
+            if (string.IsNullOrEmpty(applicationBasePath))
+            {
+                return basePath;
+            }
+            if (Path.IsPathRooted(applicationBasePath))
+            {
+                return applicationBasePath;
+            }
+            return Path.Combine(Path.GetFullPath(basePath), applicationBasePath);
+        }
+
+        private string ResolveStartupAssemblyName()
+        {
+            if (_startup != null)
+            {
+                return _startup.ConfigureDelegate.Target.GetType().GetTypeInfo().Assembly.GetName().Name;
+            }
+            if (_startupType != null)
+            {
+                return _startupType.GetTypeInfo().Assembly.GetName().Name;
+            }
+            if (!string.IsNullOrEmpty(_options.Application))
+            {
+                return _options.Application;
+            }
+            return null;
+        }
+
         private class WrappedApplicationEnvironment : IApplicationEnvironment
         {
-            public WrappedApplicationEnvironment(string applicationBasePath, IApplicationEnvironment env)
+            public WrappedApplicationEnvironment(string applicationBasePath, string applicationName, IApplicationEnvironment env)
             {
-                ApplicationBasePath = ResolvePath(applicationBasePath, env.ApplicationBasePath);
+                ApplicationBasePath = applicationBasePath;
-                ApplicationName = env.ApplicationName;
+                ApplicationName = applicationName;
                 ApplicationVersion = env.ApplicationVersion;
                 RuntimeFramework = env.RuntimeFramework;
             }
@@ -239,15 +286,5 @@ namespace Microsoft.AspNetCore.Hosting
 
             public FrameworkName RuntimeFramework { get; }
         }
-
-        private static string ResolvePath(string applicationBasePath, string basePath)
-        {
-            if (Path.IsPathRooted(applicationBasePath))
-            {
-                return applicationBasePath;
-            }
-
-            return Path.Combine(Path.GetFullPath(basePath), applicationBasePath);
-        }
     }
 }

test/Microsoft.AspNetCore.Hosting.Tests/WebHostBuilderTests.cs

@@ -14,6 +14,7 @@ using Microsoft.AspNetCore.Http.Internal;
 using Microsoft.Extensions.Configuration;
 using Microsoft.Extensions.DependencyInjection;
 using Microsoft.Extensions.PlatformAbstractions;
+using System.Reflection;
 using Xunit;
 
 namespace Microsoft.AspNetCore.Hosting
@@ -319,6 +320,53 @@ namespace Microsoft.AspNetCore.Hosting
             Assert.EndsWith(Path.DirectorySeparatorChar + "bar", basePath);
         }
 
+        [Fact]
+        public void DefaultApplicationNameToStartupAssemblyName()
+        {
+            var builder = new ConfigurationBuilder();
+            var host = new WebHostBuilder()
+                .UseServer(new TestServer())
+                .UseStartup("Microsoft.AspNetCore.Hosting.Tests")
+                .UseApplicationBasePath("/foo/bar")
+                .Build();
+
+            var appEnv = host.Services.GetService<IApplicationEnvironment>();
+            Assert.Equal("Microsoft.AspNetCore.Hosting.Tests", appEnv.ApplicationName);
+            Assert.Equal("/foo/bar", appEnv.ApplicationBasePath);
+        }
+
+        [Fact]
+        public void DefaultApplicationNameToStartupType()
+        {
+            var builder = new ConfigurationBuilder();
+            var host = new WebHostBuilder()
+                .UseServer(new TestServer())
+                .UseStartup<StartupNoServices>()
+                .UseStartup("Microsoft.AspNetCore.Hosting.Tests.NonExistent")
+                .UseApplicationBasePath("/foo/bar")
+                .Build();
+
+            var appEnv = host.Services.GetService<IApplicationEnvironment>();
+            Assert.Equal("Microsoft.AspNetCore.Hosting.Tests", appEnv.ApplicationName);
+            Assert.Equal(Path.GetDirectoryName(typeof(WebHostBuilderTests).GetTypeInfo().Assembly.Location), appEnv.ApplicationBasePath);
+        }
+
+        [Fact]
+        public void DefaultApplicationNameAndBasePathToStartupMethods()
+        {
+            var builder = new ConfigurationBuilder();
+            var host = new WebHostBuilder()
+                .UseServer(new TestServer())
+                .Configure(app => { })
+                .UseStartup("Microsoft.AspNetCore.Hosting.Tests.NonExistent")
+                .UseApplicationBasePath("/foo/bar")
+                .Build();
+
+            var appEnv = host.Services.GetService<IApplicationEnvironment>();
+            Assert.Equal("Microsoft.AspNetCore.Hosting.Tests", appEnv.ApplicationName);
+            Assert.Equal(Path.GetDirectoryName(typeof(WebHostBuilderTests).GetTypeInfo().Assembly.Location), appEnv.ApplicationBasePath);
+        }
+
         private IWebHostBuilder CreateWebHostBuilder()
         {
             var vals = new Dictionary<string, string>