Add service message types for presence API (#2121)

* Add service message type for presence API

src/Microsoft.Azure.SignalR.Protocols/Models/GroupMember.cs

@@ -0,0 +1,31 @@
+// Copyright (c) Microsoft. All rights reserved.
+// Licensed under the MIT license. See LICENSE file in the project root for full license information.
+
+using MessagePack;
+using static Microsoft.Azure.SignalR.Protocol.MessagePackUtils;
+
+namespace Microsoft.Azure.SignalR.Protocol;
+
+/// <summary>
+/// Represents a connection in a group.
+/// </summary>
+public record GroupMember : IMessagePackSerializable
+{
+    public string ConnectionId { get; set; } = string.Empty;
+
+    public string? UserId { get; set; }
+
+    void IMessagePackSerializable.Serialize(ref MessagePackWriter writer)
+    {
+        writer.WriteArrayHeader(2);
+        writer.Write(ConnectionId);
+        writer.Write(UserId);
+    }
+
+    void IMessagePackSerializable.Load(ref MessagePackReader reader, string fieldName)
+    {
+        _ = reader.ReadArrayHeader();
+        ConnectionId = ReadStringNotNull(ref reader, nameof(ConnectionId));
+        UserId = reader.ReadString();
+    }
+}

src/Microsoft.Azure.SignalR.Protocols/Models/GroupMemberQueryResponse.cs

@@ -0,0 +1,47 @@
+// Copyright (c) Microsoft. All rights reserved.
+// Licensed under the MIT license. See LICENSE file in the project root for full license information.
+
+using System.Collections.Generic;
+using MessagePack;
+
+namespace Microsoft.Azure.SignalR.Protocol;
+
+public sealed class GroupMemberQueryResponse : IMessagePackSerializable
+{
+    /// <summary>
+    /// The group members.
+    /// </summary>
+    public IReadOnlyCollection<GroupMember> Members { get; set; } = [];
+
+    /// <summary>
+    /// A token that allows the client to retrieve the next page of results. 
+    /// This parameter is provided by the service in the response of a previous request when there are additional results to be fetched. 
+    /// Clients should include the continuationToken in the next request to receive the subsequent page of data. If this parameter is omitted, the server will return the first page of results.
+    /// </summary>
+    public string? ContinuationToken { get; set; }
+
+    void IMessagePackSerializable.Serialize(ref MessagePackWriter writer)
+    {
+        writer.WriteArrayHeader(2);
+
+        writer.WriteArrayHeader(Members.Count);
+        foreach (var member in Members)
+        {
+            (member as IMessagePackSerializable).Serialize(ref writer);
+        }
+        writer.Write(ContinuationToken);
+    }
+
+    void IMessagePackSerializable.Load(ref MessagePackReader reader, string fieldName)
+    {
+        _ = reader.ReadArrayHeader();
+        var memberCount = reader.ReadArrayHeader();
+        var members = new List<GroupMember>(memberCount);
+        for (var i = 0; i < memberCount; i++)
+        {
+            members.Add(reader.Deserialize<GroupMember>("groupMembers"));
+        }
+        Members = members;
+        ContinuationToken = reader.ReadString();
+    }
+}

src/Microsoft.Azure.SignalR.Protocols/ServiceMessage.cs

@@ -572,4 +572,38 @@ public ServiceMappingMessage(string invocationId, string connectionId, string in
             InstanceId = instanceId;
         }
     }
+
+    /// <summary>
+    /// A message to list connections in a group.
+    /// </summary>
+    /// <remarks>The expected response of this message is an <see cref="AckMessage"/> whose <see cref="AckMessage.Payload"/> is a serialized <see cref="GroupMemberQueryResponse"/>.</remarks>
+    public class GroupMemberQueryMessage : ExtensibleServiceMessage, IAckableMessage, IMessageWithTracingId
+    {
+        /// <summary>
+        /// The id to ack.
+        /// </summary>
+        public int AckId { get; set; }
+
+        /// <summary>
+        /// The name of the group to list.
+        /// </summary>
+        public string GroupName { get; set; } = string.Empty;
+
+        /// <summary>
+        /// The max count of connections to return.
+        /// </summary>
+        public int Max { get; set; } = 200;
+
+        /// <summary>
+        /// A token to indiate the start point of results.
+        /// This parameter is provided by the service in the response of a previous request when there are additional results to be fetched. 
+        /// Clients should include the continuationToken in the next request to receive the subsequent page of data. If this parameter is omitted, the server will return the first page of results.
+        /// </summary>
+        public string? ContinuationToken { get; set; }
+
+        /// <summary>
+        /// The tracing id.
+        /// </summary>
+        public ulong? TracingId { get; set; }
+    }
 }

src/Microsoft.Azure.SignalR.Protocols/ServiceProtocol.cs

@@ -153,6 +153,8 @@ public bool TryParseMessage(ref ReadOnlySequence<byte> input, out ServiceMessage
                 return CreateServiceMappingMessage(ref reader, arrayLength);
             case ServiceProtocolConstants.ConnectionFlowControlMessageType:
                 return CreateConnectionFlowControlMessage(ref reader, arrayLength);
+            case ServiceProtocolConstants.GroupMemberQueryMessageType:
+                return CreateGroupMemberQueryMessage(ref reader, arrayLength);
             default:
                 // Future protocol changes can add message types, old clients can ignore them
                 return null;
@@ -336,6 +338,9 @@ private static void WriteMessageCore(ref MessagePackWriter writer, ServiceMessag
             case ConnectionFlowControlMessage connectionFlowControlMessage:
                 WriteConnectionFlowControlMessage(ref writer, connectionFlowControlMessage);
                 break;
+            case GroupMemberQueryMessage groupMemberQueryMessage:
+                WriteGroupMemberQueryMessage(ref writer, groupMemberQueryMessage);
+                break;
             default:
                 throw new InvalidDataException($"Unexpected message type: {message.GetType().Name}");
         }
@@ -751,6 +756,17 @@ private static void WriteConnectionFlowControlMessage(ref MessagePackWriter writ
         message.WriteExtensionMembers(ref writer);
     }
 
+    private static void WriteGroupMemberQueryMessage(ref MessagePackWriter writer, GroupMemberQueryMessage message)
+    {
+        writer.WriteArrayHeader(6);
+        writer.Write(ServiceProtocolConstants.GroupMemberQueryMessageType);
+        message.WriteExtensionMembers(ref writer);
+        writer.Write(message.GroupName);
+        writer.Write(message.AckId);
+        writer.Write(message.Max);
+        writer.Write(message.ContinuationToken);
+    }
+
     private static void WriteStringArray(ref MessagePackWriter writer, IReadOnlyList<string>? array)
     {
         if (array?.Count > 0)
@@ -1266,7 +1282,6 @@ private static CheckUserExistenceWithAckMessage CreateCheckUserExistenceWithAckM
     {
         var userId = ReadStringNotNull(ref reader, "userId");
         var ackId = ReadInt32(ref reader, "ackId");
-
         var result = new CheckUserExistenceWithAckMessage(userId, ackId);
         result.ReadExtensionMembers(ref reader);
         return result;
@@ -1372,4 +1387,15 @@ private static ConnectionFlowControlMessage CreateConnectionFlowControlMessage(r
             (ConnectionType)connectionType);
         return result;
     }
+
+    private static GroupMemberQueryMessage CreateGroupMemberQueryMessage(ref MessagePackReader reader, int arrayLength)
+    {
+        var result = new GroupMemberQueryMessage();
+        result.ReadExtensionMembers(ref reader);
+        result.GroupName = ReadStringNotNull(ref reader, nameof(GroupMemberQueryMessage.GroupName));
+        result.AckId = ReadInt32(ref reader, nameof(GroupMemberQueryMessage.AckId));
+        result.Max = ReadInt32(ref reader, nameof(GroupMemberQueryMessage.Max));
+        result.ContinuationToken = ReadString(ref reader, nameof(GroupMemberQueryMessage.ContinuationToken));
+        return result;
+    }
 }

test/Microsoft.Azure.SignalR.Protocols.Tests/Models/GroupMemberQueryResponsePayloadTests.cs

@@ -0,0 +1,34 @@
+// Copyright (c) Microsoft. All rights reserved.
+// Licensed under the MIT license. See LICENSE file in the project root for full license information.
+
+using System.Buffers;
+using System.Collections.Generic;
+using System.Linq;
+using Microsoft.Azure.SignalR.Protocol;
+using Xunit;
+
+namespace Microsoft.Azure.SignalR.Protocols.Tests.Models;
+public class GroupMemberQueryResponsePayloadTests
+{
+    [Fact]
+    public void TestMessagePackSerialization()
+    {
+        var groupMembers = new List<GroupMember>
+        {
+            new GroupMember { ConnectionId = "conn1", UserId = "user1" },
+            new GroupMember { ConnectionId = "conn2", UserId = "user2" }
+        };
+        var payload = new GroupMemberQueryResponse
+        {
+            Members = groupMembers,
+            ContinuationToken = "token"
+        };
+        var buffer = new ArrayBufferWriter<byte>();
+        var protocol = new ServiceProtocol();
+        protocol.WriteMessagePayload(payload, buffer);
+        var deserialized = protocol.ParseMessagePayload<GroupMemberQueryResponse>(new
+            ReadOnlySequence<byte>(buffer.WrittenMemory));
+        Assert.Equal(payload.ContinuationToken, deserialized.ContinuationToken);
+        Assert.True(payload.Members.SequenceEqual(deserialized.Members));
+    }
+}

test/Microsoft.Azure.SignalR.Protocols.Tests/Models/GroupMemberTests.cs

@@ -0,0 +1,21 @@
+// Copyright (c) Microsoft. All rights reserved.
+// Licensed under the MIT license. See LICENSE file in the project root for full license information.
+
+using System.Buffers;
+using Microsoft.Azure.SignalR.Protocol;
+using Xunit;
+
+namespace Microsoft.Azure.SignalR.Protocols.Tests.Models;
+public class GroupMemberTests
+{
+    [Fact]
+    public void TestMessagePackSerialization()
+    {
+        var groupMember = new GroupMember() { ConnectionId = "conn", UserId = "userId" };
+        var buffer = new ArrayBufferWriter<byte>();
+        var protocol = new ServiceProtocol();
+        protocol.WriteMessagePayload(groupMember, buffer);
+        var deserialized = protocol.ParseMessagePayload<GroupMember>(new ReadOnlySequence<byte>(buffer.WrittenMemory));
+        Assert.Equal(groupMember, deserialized);
+    }
+}

test/Microsoft.Azure.SignalR.Protocols.Tests/ServiceMessageEqualityComparer.cs

@@ -104,6 +104,8 @@ public bool Equals(ServiceMessage x, ServiceMessage y)
                     return ServiceMappingMessageEqual(serviceMappingMessage, (ServiceMappingMessage)y);
                 case ConnectionFlowControlMessage connectionFlowControlMessage:
                     return ConnectionFlowControlMessageEqual(connectionFlowControlMessage, (ConnectionFlowControlMessage)y);
+                case GroupMemberQueryMessage groupMemberQueryMessage:
+                    return GroupMemberQueryMessageEqual(groupMemberQueryMessage, (GroupMemberQueryMessage)y);
                 default:
                     throw new InvalidOperationException($"Unknown message type: {x.GetType().FullName}");
             }
@@ -398,6 +400,15 @@ private bool ConnectionFlowControlMessageEqual(ConnectionFlowControlMessage x, C
                 Equals(x.Operation, y.Operation);
         }
 
+        private bool GroupMemberQueryMessageEqual(GroupMemberQueryMessage x, GroupMemberQueryMessage y)
+        {
+            return x.AckId == y.AckId &&
+                   StringEqual(x.GroupName, y.GroupName) &&
+                   x.Max == y.Max &&
+                   StringEqual(x.ContinuationToken, y.ContinuationToken) &&
+                   x.TracingId == y.TracingId;
+        }
+
         private static bool StringEqual(string x, string y)
         {
             return string.Equals(x, y, StringComparison.Ordinal);

test/Microsoft.Azure.SignalR.Protocols.Tests/ServiceProtocolFacts.cs

@@ -9,8 +9,6 @@
 using System.Text;
 
 using Microsoft.Extensions.Primitives;
-using Moq;
-using Newtonsoft.Json.Linq;
 using Xunit;
 
 namespace Microsoft.Azure.SignalR.Protocol.Tests
@@ -704,6 +702,10 @@ public static IEnumerable<object[]> TestParseOldData
                 name: nameof(ConnectionFlowControlMessage) + "-2",
                 message: new ConnectionFlowControlMessage("conn2", ConnectionFlowControlOperation.Offline, ConnectionType.Server),
                 binary: "lSelY29ubjLSAAAAAtIAAAAEgA=="),
+            new ProtocolTestData(
+                name: "GroupMemberQueryMessage",
+                message: new GroupMemberQueryMessage() { GroupName = "group", AckId = 1, Max = 10, ContinuationToken = "token", TracingId = 1234UL },
+                binary: "liiBAc0E0qVncm91cAEKpXRva2Vu"),
         }.ToDictionary(t => t.Name);
 
 #pragma warning restore CS0618 // Type or member is obsolete