Update API of ServerlessHub<T> according to the review meeting (Azure#25834)

* Update API of ServerlessHub<T> according to the review meeting

* Rename `Event` -> `SignalRTriggerEvents`, `Category` -> `SignalRTriggerCategories`

* Update Azure SignalR SDK to 1.15.0

Why TFM .netcoreapp3.1 deleted: The `JsonHubProtocol` of ASP.NET SignalR uses `Newtonsoft.Json` for netcoreapp 2.1 and uses `System.Text.Json` for netcore3.1 and above. However, function host always uses `Newtonsoft.Json` to parse JSON data sent from isolated worker, and SignalR fails to serialize `Newtonsoft.Json.JObject` on .NET Core 3.1 correctly. In the past, SignalR SDK and extensions enabled `NewtonsoftJsonHubProtocol` (not available on .NET Core 2.1) on .NET Core 3.1 with isolated function workers only, so they had to use framework-sensitive conditional compilation. Since SignalR SDK 1.15.0, we have a new hub protocol accepting a `ObjectSerializer`, which is available on .NET Standard 2.0, so framework-sensitive conditional is unecessary.

* Update

* Add `SignalRConnectionAttribute` for `ServerlessHub<T>`

* Fix for SignalRConnectionAttribute

* Fix

* Remove unused using.

Author: Y-Sindo

eng/Packages.Data.props

@@ -119,11 +119,9 @@
     <PackageReference Update="Apache.Avro" Version="1.11.0" />
     <PackageReference Update="CloudNative.CloudEvents" Version="2.0.0" />
     <PackageReference Update="CloudNative.CloudEvents.SystemTextJson" Version="2.0.0" />
-    <PackageReference Update="Microsoft.AspNetCore.SignalR.Protocols.NewtonsoftJson" Version="3.0.0" Condition="'$(TargetFramework)' == 'netcoreapp3.1'" />
-    <PackageReference Update="Microsoft.AspNetCore.SignalR.Protocols.NewtonsoftJson" Version="5.0.1" Condition="'$(TargetFramework)' == 'net5.0'" />
-    <PackageReference Update="Microsoft.Azure.SignalR" Version="1.13.0" />
-    <PackageReference Update="Microsoft.Azure.SignalR.Management" Version="1.13.0" />
-    <PackageReference Update="Microsoft.Azure.SignalR.Protocols" Version="1.13.0" />
+    <PackageReference Update="Microsoft.Azure.SignalR" Version="1.15.0" />
+    <PackageReference Update="Microsoft.Azure.SignalR.Management" Version="1.15.0" />
+    <PackageReference Update="Microsoft.Azure.SignalR.Protocols" Version="1.15.0" />
     <PackageReference Update="Microsoft.Azure.SignalR.Serverless.Protocols" Version="1.6.0" />
     <PackageReference Update="Microsoft.Azure.WebJobs" Version="3.0.31" />
     <PackageReference Update="Microsoft.Azure.WebJobs.Sources" Version="3.0.30" />

sdk/signalr/Microsoft.Azure.WebJobs.Extensions.SignalRService/Microsoft.Azure.WebJobs.Extensions.SignalRService.sln

@@ -14,7 +14,6 @@ Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "Microsoft.Azure.WebJobs.Ext
 EndProject
 Project("{2150E333-8FDC-42A3-9474-1A3956D46DE8}") = "Api", "Api", "{25AE2C7A-FD10-4A94-A063-857C542B7D45}"
 	ProjectSection(SolutionItems) = preProject
-		api\Microsoft.Azure.WebJobs.Extensions.SignalRService.netcoreapp3.1.cs = api\Microsoft.Azure.WebJobs.Extensions.SignalRService.netcoreapp3.1.cs
 		api\Microsoft.Azure.WebJobs.Extensions.SignalRService.netstandard2.0.cs = api\Microsoft.Azure.WebJobs.Extensions.SignalRService.netstandard2.0.cs
 	EndProjectSection
 EndProject

sdk/signalr/Microsoft.Azure.WebJobs.Extensions.SignalRService/api/Microsoft.Azure.WebJobs.Extensions.SignalRService.netcoreapp3.1.cs

@@ -1,10 +1,12 @@
 namespace Microsoft.Azure.WebJobs.Extensions.SignalRService
 {
+    [System.ComponentModel.EditorBrowsableAttribute(System.ComponentModel.EditorBrowsableState.Never)]
     public static partial class Category
     {
         public const string Connections = "connections";
         public const string Messages = "messages";
     }
+    [System.ComponentModel.EditorBrowsableAttribute(System.ComponentModel.EditorBrowsableState.Never)]
     public static partial class Event
     {
         public const string Connected = "connected";
@@ -114,12 +116,14 @@ public SignalRConnectionAttribute(string connectionStringSetting) { }
     }
     public abstract partial class ServerlessHub<T> where T : class
     {
-        protected ServerlessHub(Microsoft.Azure.SignalR.Management.ServiceHubContext<T> serviceHubContext = null) { }
+        protected ServerlessHub() { }
+        protected ServerlessHub(Microsoft.Azure.SignalR.Management.ServiceHubContext<T> serviceHubContext) { }
         public Microsoft.Azure.SignalR.Management.ClientManager ClientManager { get { throw null; } }
         public Microsoft.AspNetCore.SignalR.IHubClients<T> Clients { get { throw null; } }
         public Microsoft.Azure.SignalR.Management.GroupManager Groups { get { throw null; } }
+        public string HubName { get { throw null; } }
         public Microsoft.Azure.SignalR.Management.UserGroupManager UserGroups { get { throw null; } }
-        protected static System.Collections.Generic.IList<System.Security.Claims.Claim> GetClaims(string jwt) { throw null; }
+        protected System.Collections.Generic.IList<System.Security.Claims.Claim> GetClaims(string jwt) { throw null; }
         protected System.Threading.Tasks.Task<Microsoft.Azure.WebJobs.Extensions.SignalRService.SignalRConnectionInfo> NegotiateAsync(Microsoft.Azure.SignalR.Management.NegotiationOptions options) { throw null; }
     }
     public partial class SignalRAsyncCollector<T> : Microsoft.Azure.WebJobs.IAsyncCollector<T>
@@ -137,6 +141,12 @@ public SignalRAttribute() { }
         [Microsoft.Azure.WebJobs.Description.AutoResolveAttribute]
         public string HubName { get { throw null; } set { } }
     }
+    [System.AttributeUsageAttribute(System.AttributeTargets.Class)]
+    public partial class SignalRConnectionAttribute : System.Attribute, Microsoft.Azure.WebJobs.IConnectionProvider
+    {
+        public SignalRConnectionAttribute(string connection) { }
+        public string Connection { get { throw null; } set { } }
+    }
     public partial class SignalRConnectionDetail
     {
         public SignalRConnectionDetail() { }
@@ -249,6 +259,16 @@ public SignalRTriggerAttribute(string hubName, string category, string @event, p
         public string HubName { get { throw null; } }
         public string[] ParameterNames { get { throw null; } }
     }
+    public static partial class SignalRTriggerCategories
+    {
+        public const string Connections = "connections";
+        public const string Messages = "messages";
+    }
+    public static partial class SignalRTriggerEvents
+    {
+        public const string Connected = "connected";
+        public const string Disconnected = "disconnected";
+    }
     public partial class SignalRTriggerException : System.Exception
     {
         public SignalRTriggerException() { }

sdk/signalr/Microsoft.Azure.WebJobs.Extensions.SignalRService/api/Microsoft.Azure.WebJobs.Extensions.SignalRService.netstandard2.0.cs

@@ -1,12 +1,15 @@
 // Copyright (c) Microsoft Corporation. All rights reserved.
 // Licensed under the MIT License.
 
+using System.ComponentModel;
+
 namespace Microsoft.Azure.WebJobs.Extensions.SignalRService
 {
     /// <summary>
     /// A class contains constant strings that represent SignalR trigger category.
     /// </summary>
     [System.Diagnostics.CodeAnalysis.SuppressMessage("Usage", "AZC0012:Avoid single word type names", Justification = "Breaking change")]
+    [EditorBrowsable(EditorBrowsableState.Never)]
     public static class Category
     {
         /// <summary>

sdk/signalr/Microsoft.Azure.WebJobs.Extensions.SignalRService/src/Category.cs

@@ -1,23 +1,18 @@
 // Copyright (c) Microsoft Corporation. All rights reserved.
 // Licensed under the MIT License.
-#if NETCOREAPP3_1
-using Microsoft.AspNetCore.SignalR.Protocol;
 
 namespace Microsoft.Azure.WebJobs.Extensions.SignalRService
 {
     internal enum HubProtocol
     {
         /// <summary>
         /// Implements the SignalR Hub Protocol using System.Text.Json.
-        /// <see cref="JsonHubProtocol"/>
         /// </summary>
         SystemTextJson,
 
         /// <summary>
         /// Implements the SignalR Hub Protocol using Newtonsoft.Json.
-        /// <see cref="NewtonsoftJsonHubProtocol "/>
         /// </summary>
         NewtonsoftJson
     }
-}
-#endif
+}

sdk/signalr/Microsoft.Azure.WebJobs.Extensions.SignalRService/src/Config/DependencyInjectionExtensions.cs

@@ -3,9 +3,12 @@
 
 using System;
 using System.Collections.Generic;
+using Azure.Core.Serialization;
 using Microsoft.Azure.SignalR;
 using Microsoft.Extensions.Azure;
 using Microsoft.Extensions.Configuration;
+using Newtonsoft.Json;
+using Newtonsoft.Json.Serialization;
 
 namespace Microsoft.Azure.WebJobs.Extensions.SignalRService
 {
@@ -65,5 +68,45 @@ public static bool TryGetNamedEndpointFromIdentity(this IConfigurationSection se
             endpoint = null;
             return false;
         }
+
+        public static bool TryGetJsonObjectSerializer(this IConfiguration configuration, out ObjectSerializer serializer)
+        {
+            //indicates Newtonsoft, camcelCase
+            if (configuration.GetValue(Constants.AzureSignalRNewtonsoftCamelCase, false))
+            {
+                serializer = new NewtonsoftJsonObjectSerializer(new JsonSerializerSettings()
+                {
+                    ContractResolver = new CamelCasePropertyNamesContractResolver()
+                });
+                return true;
+            }
+
+            if (!configuration.OnDotnetInProcessRuntime())
+            {
+                serializer = new NewtonsoftJsonObjectSerializer();
+                return true;
+            }
+
+            var hubProtocolConfig = configuration[Constants.AzureSignalRHubProtocol];
+            if (hubProtocolConfig is not null)
+            {
+                serializer = Enum.Parse(typeof(HubProtocol), hubProtocolConfig, true) switch
+                {
+                    HubProtocol.NewtonsoftJson => new NewtonsoftJsonObjectSerializer(),
+                    HubProtocol.SystemTextJson => new JsonObjectSerializer(),
+                    _ => throw new NotSupportedException($"The {Constants.AzureSignalRHubProtocol} setting value '{hubProtocolConfig}' is not supported."),
+                };
+                return true;
+            }
+            serializer = null;
+            return false;
+        }
+
+        private static bool OnDotnetInProcessRuntime(this IConfiguration configuration)
+        {
+            var workerRuntime = configuration[Constants.FunctionsWorkerRuntime];
+            //unit test environment
+            return workerRuntime == null || workerRuntime == Constants.DotnetWorker;
+        }
     }
 }

sdk/signalr/Microsoft.Azure.WebJobs.Extensions.SignalRService/src/Config/HubProtocol.cs

@@ -42,6 +42,11 @@ public OptionsSetup(IConfiguration configuration, ILoggerFactory loggerFactory,
 
         public void Configure(ServiceManagerOptions options)
         {
+            if (_configuration.TryGetJsonObjectSerializer(out var serializer))
+            {
+                options.UseJsonObjectSerializer(serializer);
+            }
+
             options.ConnectionString = _configuration.GetConnectionString(_connectionStringKey) ?? _configuration[_connectionStringKey];
             var endpoints = _configuration.GetSection(Constants.AzureSignalREndpoints).GetEndpoints(_azureComponentFactory);
             // Fall back to use a section to configure Azure identity

sdk/signalr/Microsoft.Azure.WebJobs.Extensions.SignalRService/src/Config/IConfigurationExtensions.cs

@@ -65,7 +65,6 @@ private IInternalServiceHubContextStore CreateHubContextStore(string connectionS
             {
                 services.AddSingleton(_router);
             }
-            services.SetHubProtocol(_configuration);
             services.AddSingleton(services.ToList() as IReadOnlyCollection<ServiceDescriptor>);
             return services.BuildServiceProvider()
                .GetRequiredService<IInternalServiceHubContextStore>();