Add preview banner

src/AccountDeleter/EmptyFeatureFlagService.cs

@@ -76,6 +76,11 @@ public bool IsDisplayPackagePageV2Enabled(User user)
             throw new NotImplementedException();
         }
 
+        public bool IsDisplayPackagePageV2PreviewEnabled(User user)
+        {
+            throw new NotImplementedException();
+        }
+
         public bool IsDisplayVulnerabilitiesEnabled()
         {
             throw new NotImplementedException();

src/GitHubVulnerabilities2Db/Fakes/FakeFeatureFlagService.cs

@@ -264,5 +264,10 @@ public bool IsDisplayNuGetPackageExplorerLinkEnabled()
         {
             throw new NotImplementedException();
         }
+
+        public bool IsDisplayPackagePageV2PreviewEnabled(User user)
+        {
+            throw new NotImplementedException();
+        }
     }
 }

src/NuGetGallery.Services/Configuration/FeatureFlagService.cs

@@ -49,6 +49,7 @@ public class FeatureFlagService : IFeatureFlagService
         private const string DeletePackageApiFlightName = GalleryPrefix + "DeletePackageApi";
         private const string ImageAllowlistFlightName = GalleryPrefix + "ImageAllowlist";
         private const string DisplayBannerFlightName = GalleryPrefix + "Banner";
+        private const string DisplayPackagePageV2PreviewFeatureName = GalleryPrefix + "DisplayPackagePageV2Preview";
         private const string DisplayPackagePageV2FeatureName = GalleryPrefix + "DisplayPackagePageV2";
         private const string ShowReportAbuseSafetyChanges = GalleryPrefix + "ShowReportAbuseSafetyChanges";
 
@@ -246,6 +247,11 @@ public bool AreEmbeddedReadmesEnabled(User user)
             return _client.IsEnabled(EmbeddedReadmeFlightName, user, defaultValue: false);
         }
 
+        public bool IsDisplayPackagePageV2PreviewEnabled(User user)
+        {
+            return _client.IsEnabled(DisplayPackagePageV2PreviewFeatureName, user, defaultValue: false);
+        }
+
         public bool IsDisplayPackagePageV2Enabled(User user) 
         {
             return _client.IsEnabled(DisplayPackagePageV2FeatureName, user, defaultValue: false);

src/NuGetGallery.Services/Configuration/IFeatureFlagService.cs

@@ -178,6 +178,11 @@ public interface IFeatureFlagService
         /// </summary>
         bool AreEmbeddedReadmesEnabled(User user);
 
+        /// <summary>
+        /// Whether the preview of the new design of the display package page is enabled.
+        /// </summary>
+        bool IsDisplayPackagePageV2PreviewEnabled(User user);
+
         /// <summary>
         /// Whether the new design of the display package page is enabled.
         /// </summary>

src/NuGetGallery/App_Data/Files/Content/flags.json

@@ -103,6 +103,12 @@
       "SiteAdmins": false,
       "Accounts": [],
       "Domains": []
+    },
+    "NuGetGallery.DisplayPackagePageV2Preview": {
+      "All": true,
+      "SiteAdmins": false,
+      "Accounts": [],
+      "Domains": []
     }
   }
 }

src/NuGetGallery/Controllers/PackagesController.cs

@@ -872,7 +872,7 @@ public HttpStatusCodeResult DisplayPackage()
             => new HttpStatusCodeWithHeadersResult(HttpStatusCode.MethodNotAllowed, new NameValueCollection() { { "allow", "GET" } });
 
         [HttpGet]
-        public virtual async Task<ActionResult> DisplayPackage(string id, string version)
+        public virtual async Task<ActionResult> DisplayPackage(string id, string version, string preview = null)
         {
             // Attempt to normalize the version but allow version strings that are not actually SemVer strings. For
             // example, "absoluteLatest" is allowed as the version string as a reference to the absolute latest version
@@ -1034,7 +1034,28 @@ public virtual async Task<ActionResult> DisplayPackage(string id, string version
             }
             ViewBag.FacebookAppID = _config.FacebookAppId;
 
-            if (_featureFlagService.IsDisplayPackagePageV2Enabled(GetCurrentUser())) 
+            var enableRedesign = _featureFlagService.IsDisplayPackagePageV2Enabled(currentUser);
+
+            if (_featureFlagService.IsDisplayPackagePageV2PreviewEnabled(currentUser))
+            {
+                if (!string.IsNullOrEmpty(preview))
+                {
+                    enableRedesign = true;
+                }
+
+                // If the user is on the current design, show the banner to preview the redesign.
+                // If the user is on the preview design, show the banner that links to the feedback survey.
+                ViewBag.ShowRedesignPreviewBanner = !enableRedesign;
+                ViewBag.ShowRedesignSurveyBanner = enableRedesign;
+                ViewBag.ShowRedesignUrl = Url.Package(package, preview: true);
+            }
+            else
+            {
+                ViewBag.ShowRedesignPreviewBanner = false;
+                ViewBag.ShowRedesignSurveyBanner = false;
+            }
+
+            if (enableRedesign)
             { 
                 return View("DisplayPackageV2", model);
             }
@@ -2986,7 +3007,11 @@ public virtual async Task<JsonResult> GetReadMeMd(string id, string version)
         [ValidateAntiForgeryToken]
         public virtual async Task<ActionResult> SetLicenseReportVisibility(string id, string version, bool visible)
         {
-            return await SetLicenseReportVisibility(id, version, visible, Url.Package);
+            return await SetLicenseReportVisibility(
+                id,
+                version,
+                visible,
+                (package, relativeUrl) => Url.Package(package, relativeUrl));
         }
 
         internal virtual async Task<ActionResult> SetLicenseReportVisibility(string id, string version, bool visible, Func<Package, bool, string> urlFactory)

src/NuGetGallery/UrlHelperExtensions.cs

@@ -225,27 +225,33 @@ public static string Package(
             this UrlHelper url,
             string id,
             string version,
-            bool relativeUrl = true)
+            bool relativeUrl = true,
+            bool preview = false)
         {
-            string normalized = (version != null) ? NuGetVersionFormatter.Normalize(version) : version;
+            var normalized = (version != null) ? NuGetVersionFormatter.Normalize(version) : version;
 
-            string result = GetRouteLink(
+            var result = GetRouteLink(
                 url,
                 RouteName.DisplayPackage,
                 relativeUrl,
                 routeValues: new RouteValueDictionary
                 {
                     { "id", id },
-                    { "version", normalized }
+                    { "version", normalized },
+                    { "preview", preview ? "1" : null }
                 });
 
             // Ensure trailing slashes for versionless package URLs, as a fix for package filenames that look like known file extensions
             return version == null ? EnsureTrailingSlash(result) : result;
         }
 
-        public static string Package(this UrlHelper url, Package package, bool relativeUrl = true)
+        public static string Package(
+            this UrlHelper url,
+            Package package,
+            bool relativeUrl = true,
+            bool preview = false)
         {
-            return url.Package(package.PackageRegistration.Id, package.NormalizedVersion, relativeUrl);
+            return url.Package(package.PackageRegistration.Id, package.NormalizedVersion, relativeUrl, preview);
         }
 
         public static string Package(this UrlHelper url, IPackageVersionModel package, bool relativeUrl = true)

src/NuGetGallery/Views/Shared/Gallery/Header.cshtml

@@ -22,7 +22,7 @@
     </div>
 }
 
-@if (ViewBag.DisplayBanner == true)
+@if (ViewBag.DisplayBanner == true)
 {
     <div class="container-fluid banner banner-info text-center">
         <div class="row">
@@ -35,6 +35,35 @@
     </div>
 }
 
+@if (ViewBag.ShowRedesignPreviewBanner == true)
+{
+    <div class="container-fluid banner banner-info text-center">
+        <div class="row">
+            <div class="col-sm-12">
+                <span>
+                    &#128075; Changes are coming to this page!
+                    Test out the <a href="@ViewBag.ShowRedesignUrl">new design</a> and
+                    <a href="https://aka.ms/NuGetRedesignSurvey" target="_blank">tell us what you think</a>.
+                </span>
+            </div>
+        </div>
+    </div>
+}
+
+@if (ViewBag.ShowRedesignSurveyBanner == true)
+{
+    <div class="container-fluid banner banner-info text-center">
+        <div class="row">
+            <div class="col-sm-12">
+                <span>
+                    &#128075; What do you think about the new design?
+                    <a href="https://aka.ms/NuGetRedesignSurvey" target="_blank">Take the survey (3 min.)</a>
+                </span>
+            </div>
+        </div>
+    </div>
+}
+
 @helper DisplayNavigationItem(string tab, string url, bool bold = false, string title = null)
 {
     <li class="@(ViewBag.Tab == tab ? "active" : string.Empty)" role="presentation">

src/VerifyMicrosoftPackage/Fakes/FakeFeatureFlagService.cs

@@ -114,5 +114,10 @@ public class FakeFeatureFlagService : IFeatureFlagService
         public bool IsDisplayBannerEnabled() => throw new NotImplementedException();
 
         public bool IsDisplayNuGetPackageExplorerLinkEnabled() => throw new NotImplementedException();
+
+        public bool IsDisplayPackagePageV2PreviewEnabled(User user)
+        {
+            throw new NotImplementedException();
+        }
     }
 }

tests/NuGetGallery.Facts/Controllers/PackagesControllerFacts.cs

@@ -239,6 +239,9 @@ private static PackagesController CreateController(
                 featureFlagService
                     .Setup(x => x.IsDisplayPackagePageV2Enabled(It.IsAny<User>()))
                     .Returns(false);
+                featureFlagService
+                    .Setup(x => x.IsDisplayPackagePageV2PreviewEnabled(It.IsAny<User>()))
+                    .Returns(false);
             }
 
             renameService = renameService ?? new Mock<IPackageRenameService>();
@@ -1167,9 +1170,21 @@ public async Task GetsValidationIssues()
             }
 
             [Theory]
-            [InlineData(true, "DisplayPackageV2")]
-            [InlineData(false, "DisplayPackage")]
-            public async Task DisplayPackageV2(bool isDisplayV2Enabled, String expectedViewName)
+            [InlineData(false, false, null, "DisplayPackage", false, false)]
+            [InlineData(false, false, "1", "DisplayPackage", false, false)]
+            [InlineData(false, true, null, "DisplayPackage", true, false)]
+            [InlineData(false, true, "1", "DisplayPackageV2", false, true)]
+            [InlineData(true, false, null, "DisplayPackageV2", false, false)]
+            [InlineData(true, false, "1", "DisplayPackageV2", false, false)]
+            [InlineData(true, true, null, "DisplayPackageV2", false, true)]
+            [InlineData(true, true, "1", "DisplayPackageV2", false, true)]
+            public async Task DisplayPackageV2(
+                bool enableV2,
+                bool enablePreview,
+                string previewParam,
+                string expectedViewName,
+                bool expectPreviewBanner,
+                bool expectSurveyBanner)
             {
                 // Arrange
                 var packageService = new Mock<IPackageService>();
@@ -1198,23 +1213,35 @@ public async Task DisplayPackageV2(bool isDisplayV2Enabled, String expectedViewN
                 };
 
                 var packages = new[] { package };
-                packageService.Setup(p => p.FindPackagesById("Foo", /*includePackageRegistration:*/ true))
+                packageService
+                    .Setup(p => p.FindPackagesById("Foo", /*includePackageRegistration:*/ true))
                     .Returns(packages);
 
-                packageService.Setup(p => p.FilterLatestPackage(packages, SemVerLevelKey.SemVer2, true))
+                packageService
+                    .Setup(p => p.FilterLatestPackage(packages, SemVerLevelKey.SemVer2, true))
                     .Returns(package);
 
-                indexingService.Setup(i => i.GetLastWriteTime()).Returns(Task.FromResult((DateTime?)DateTime.UtcNow));
+                indexingService
+                    .Setup(i => i.GetLastWriteTime())
+                    .Returns(Task.FromResult((DateTime?)DateTime.UtcNow));
 
                 featureFlag
                     .Setup(x => x.IsDisplayPackagePageV2Enabled(It.IsAny<User>()))
-                    .Returns(isDisplayV2Enabled);
+                    .Returns(enableV2);
+                featureFlag
+                    .Setup(x => x.IsDisplayPackagePageV2PreviewEnabled(It.IsAny<User>()))
+                    .Returns(enablePreview);
 
                 // Act
-                var result = await controller.DisplayPackage("Foo", version: null);
+                var result = await controller.DisplayPackage("Foo", version: null, preview: previewParam);
 
                 // Assert
                 ResultAssert.IsView<DisplayPackageViewModel>(result, expectedViewName);
+
+                var view = (ViewResult)result;
+
+                Assert.Equal(expectPreviewBanner, view.ViewBag.ShowRedesignPreviewBanner);
+                Assert.Equal(expectSurveyBanner, view.ViewBag.ShowRedesignSurveyBanner);
             }
 
             [Theory]

tests/NuGetGallery.Facts/UrlHelperExtensionsFacts.cs

@@ -77,11 +77,15 @@ public void UsesNormalizedVersionInUrls()
             }
 
             [Theory]
-            [InlineData("https://nuget.org", true, "/packages/id/1.0.0")]
-            [InlineData("https://nuget.org", false, "https://nuget.org/packages/id/1.0.0")]
-            [InlineData("https://localhost:66", true, "/packages/id/1.0.0")]
-            [InlineData("https://localhost:66", false, "https://localhost:66/packages/id/1.0.0")]
-            public void ReturnsCorrectRouteLink(string siteRoot, bool relativeUrl, string expectedUrl)
+            [InlineData("https://nuget.org", true, false, "/packages/id/1.0.0")]
+            [InlineData("https://nuget.org", false, false, "https://nuget.org/packages/id/1.0.0")]
+            [InlineData("https://localhost:66", true, false, "/packages/id/1.0.0")]
+            [InlineData("https://localhost:66", false, false, "https://localhost:66/packages/id/1.0.0")]
+            [InlineData("https://nuget.org", true, true, "/packages/id/1.0.0?preview=1")]
+            [InlineData("https://nuget.org", false, true, "https://nuget.org/packages/id/1.0.0?preview=1")]
+            [InlineData("https://localhost:66", true, true, "/packages/id/1.0.0?preview=1")]
+            [InlineData("https://localhost:66", false, true, "https://localhost:66/packages/id/1.0.0?preview=1")]
+            public void ReturnsCorrectRouteLink(string siteRoot, bool relativeUrl, bool preview, string expectedUrl)
             {
                 // Arrange
                 var configurationService = GetConfigurationService();
@@ -90,7 +94,7 @@ public void ReturnsCorrectRouteLink(string siteRoot, bool relativeUrl, string ex
                 var urlHelper = TestUtility.MockUrlHelper(siteRoot);
 
                 // Act
-                var result = urlHelper.Package("id", "1.0.0", relativeUrl);
+                var result = urlHelper.Package("id", "1.0.0", relativeUrl, preview);
 
                 // Assert
                 Assert.Equal(expectedUrl, result);