Add X-NuGet-Warning header to response when pushing SemVer2 package

src/NuGetGallery/Controllers/ApiController.cs

@@ -508,6 +508,11 @@ await AuditingService.SaveAuditRecordAsync(
 
                         TelemetryService.TrackPackagePushEvent(package, user, User.Identity);
 
+                        if (package.SemVerLevelKey == SemVerLevelKey.SemVer2)
+                        {
+                            return new HttpStatusCodeWithServerWarningResult(HttpStatusCode.Created, Strings.WarningSemVer2PackagePushed);
+                        }
+
                         return new HttpStatusCodeResult(HttpStatusCode.Created);
                     }
                 }

src/NuGetGallery/Infrastructure/HttpStatusCodeWithServerWarningResult.cs

@@ -0,0 +1,32 @@
+// Copyright (c) .NET Foundation. All rights reserved.
+// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
+
+using System.Net;
+using System.Web.Mvc;
+using NuGet.Protocol;
+
+namespace NuGetGallery
+{
+    public class HttpStatusCodeWithServerWarningResult : HttpStatusCodeResult
+    {
+        private readonly string _warningMessage;
+
+        public HttpStatusCodeWithServerWarningResult(HttpStatusCode statusCode, string warningMessage)
+            : base((int)statusCode)
+        {
+            _warningMessage = warningMessage;
+        }
+
+        public override void ExecuteResult(ControllerContext context)
+        {
+            var response = context.RequestContext.HttpContext.Response;
+
+            if (!string.IsNullOrEmpty(_warningMessage) && !response.HeadersWritten)
+            {
+                response.AppendHeader(ProtocolConstants.ServerWarningHeader, _warningMessage);
+            }
+
+            base.ExecuteResult(context);
+        }
+    }
+}

src/NuGetGallery/NuGetGallery.csproj

@@ -743,6 +743,7 @@
     <Compile Include="Controllers\PagesController.cs" />
     <Compile Include="Filters\ApiScopeRequiredAttribute.cs" />
     <Compile Include="GlobalSuppressions.cs" />
+    <Compile Include="Infrastructure\HttpStatusCodeWithServerWarningResult.cs" />
     <Compile Include="Migrations\201704191802404_AddIndexPackageRegistrationKeySemVer.cs" />
     <Compile Include="Migrations\201704191802404_AddIndexPackageRegistrationKeySemVer.Designer.cs">
       <DependentUpon>201704191802404_AddIndexPackageRegistrationKeySemVer.cs</DependentUpon>

src/NuGetGallery/Strings.resx

@@ -522,4 +522,7 @@ For more information, please contact '{2}'.</value>
 &lt;li&gt;All existing push API keys for co-owners new to this policy will expire in {1} days.&lt;/li&gt;
 &lt;/ol&gt;</value>
   </data>
+  <data name="WarningSemVer2PackagePushed" xml:space="preserve">
+    <value>This package will only be available to download with SemVer 2.0.0 compatible NuGet clients, such as Visual Studio 2017 (version 15.3) and above or NuGet client 4.3 and above. For more information, see https://go.microsoft.com/fwlink/?linkid=852248.</value>
+  </data>
 </root>

tests/NuGetGallery.Facts/App.config

@@ -112,6 +112,10 @@
         <assemblyIdentity name="NuGet.Packaging.Core" publicKeyToken="31bf3856ad364e35" culture="neutral" />
         <bindingRedirect oldVersion="0.0.0.0-4.3.0.0" newVersion="4.3.0.0" />
       </dependentAssembly>
+      <dependentAssembly>
+        <assemblyIdentity name="Microsoft.ApplicationInsights" publicKeyToken="31bf3856ad364e35" culture="neutral" />
+        <bindingRedirect oldVersion="0.0.0.0-2.2.0.0" newVersion="2.2.0.0" />
+      </dependentAssembly>
     </assemblyBinding>
   </runtime>
   <startup>

tests/NuGetGallery.Facts/Controllers/ApiControllerFacts.cs

@@ -15,6 +15,7 @@
 using Moq;
 using Newtonsoft.Json.Linq;
 using NuGet.Packaging;
+using NuGet.Protocol;
 using NuGetGallery.Auditing;
 using NuGetGallery.Authentication;
 using NuGetGallery.Configuration;
@@ -86,6 +87,7 @@ public TestableApiController(MockBehavior behavior = MockBehavior.Default)
                     var package = new Package();
                     package.PackageRegistration = new PackageRegistration { Id = packageMetadata.Id };
                     package.Version = packageMetadata.Version.ToString();
+                    package.SemVerLevelKey = SemVerLevelKey.ForPackage(packageMetadata.Version, packageMetadata.GetDependencyGroups().AsPackageDependencyEnumerable());
 
                     return Task.FromResult(package);
                 });
@@ -481,6 +483,21 @@ public async Task WillCreateAPackageFromTheNuGetPackage()
                 controller.MockEntitiesContext.VerifyCommitted();
             }
 
+            [Fact]
+            public async Task WillReturnServerWarningWhenCreatingSemVer2Package()
+            {
+                var nuGetPackage = TestPackage.CreateTestPackageStream("theId", "1.0.42+metadata");
+
+                var user = new User() { EmailAddress = "confirmed@email.com" };
+                var controller = new TestableApiController();
+                controller.SetCurrentUser(user);
+                controller.SetupPackageFromInputStream(nuGetPackage);
+
+                var actionResult = await controller.CreatePackagePut();
+
+                Assert.IsType<HttpStatusCodeWithServerWarningResult>(actionResult);
+            }
+
             [Fact]
             public async Task WillCurateThePackage()
             {

tests/NuGetGallery.Facts/NuGetGallery.Facts.csproj

@@ -199,6 +199,9 @@
     <Reference Include="NuGet.Common, Version=4.3.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35, processorArchitecture=MSIL">
       <HintPath>..\..\packages\NuGet.Common.4.3.0-preview1-2524\lib\net45\NuGet.Common.dll</HintPath>
     </Reference>
+    <Reference Include="NuGet.Configuration, Version=4.3.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35, processorArchitecture=MSIL">
+      <HintPath>..\..\packages\NuGet.Configuration.4.3.0-preview1-2524\lib\net45\NuGet.Configuration.dll</HintPath>
+    </Reference>
     <Reference Include="NuGet.Frameworks, Version=4.3.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35, processorArchitecture=MSIL">
       <HintPath>..\..\packages\NuGet.Frameworks.4.3.0-preview1-2524\lib\net45\NuGet.Frameworks.dll</HintPath>
     </Reference>
@@ -213,6 +216,9 @@
     <Reference Include="NuGet.Packaging.Core, Version=4.3.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35, processorArchitecture=MSIL">
       <HintPath>..\..\packages\NuGet.Packaging.Core.4.3.0-preview1-2524\lib\net45\NuGet.Packaging.Core.dll</HintPath>
     </Reference>
+    <Reference Include="NuGet.Protocol, Version=4.3.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35, processorArchitecture=MSIL">
+      <HintPath>..\..\packages\NuGet.Protocol.4.3.0-preview1-2524\lib\net45\NuGet.Protocol.dll</HintPath>
+    </Reference>
     <Reference Include="NuGet.Services.KeyVault, Version=1.0.0.0, Culture=neutral, processorArchitecture=MSIL">
       <HintPath>..\..\packages\NuGet.Services.KeyVault.1.0.0.0\lib\net45\NuGet.Services.KeyVault.dll</HintPath>
       <Private>True</Private>

tests/NuGetGallery.Facts/packages.config

@@ -39,10 +39,12 @@
   <package id="MvcHaack.Ajax.MVC4" version="2.0.0.0" targetFramework="net46" />
   <package id="Newtonsoft.Json" version="9.0.1" targetFramework="net46" />
   <package id="NuGet.Common" version="4.3.0-preview1-2524" targetFramework="net46" />
+  <package id="NuGet.Configuration" version="4.3.0-preview1-2524" targetFramework="net46" />
   <package id="NuGet.Frameworks" version="4.3.0-preview1-2524" targetFramework="net46" />
   <package id="NuGet.Logging" version="3.5.0-beta-1160" targetFramework="net46" />
   <package id="NuGet.Packaging" version="4.3.0-preview1-2524" targetFramework="net46" />
   <package id="NuGet.Packaging.Core" version="4.3.0-preview1-2524" targetFramework="net46" />
+  <package id="NuGet.Protocol" version="4.3.0-preview1-2524" targetFramework="net46" />
   <package id="NuGet.Services.KeyVault" version="1.0.0.0" targetFramework="net46" />
   <package id="NuGet.Versioning" version="4.3.0-preview1-2524" targetFramework="net46" />
   <package id="Owin" version="1.0" targetFramework="net46" />