Shaker/Communication/NetMQ/Sockets/PairSocket.cs

using System;
using System.Threading;
using NetMQ.Core;

namespace NetMQ.Sockets
{
    /// <summary>
    /// A PairSocket is a NetMQSocket, usually used to synchronize two threads - using only one socket on each side.
    /// </summary>
    public class PairSocket : NetMQSocket
    {
        private static int s_sequence;

        /// <summary>
        /// Create a new PairSocket and attach socket to zero or more endpoints.
        /// </summary>
        /// <param name="connectionString">List of NetMQ endpoints, separated by commas and prefixed by '@' (to bind the socket) or '>' (to connect the socket).
        /// Default action is connect (if endpoint doesn't start with '@' or '>')</param>
        /// <example><code>var socket = new PairSocket(">tcp://127.0.0.1:5555,@tcp://127.0.0.1:55556");</code></example>
        public PairSocket(string? connectionString = null) : base(ZmqSocketType.Pair, connectionString, DefaultAction.Connect)
        {
        }

        /// <summary>
        /// Create a new PairSocket based upon the given SocketBase.
        /// </summary>
        /// <param name="socketHandle">the SocketBase to create the new socket from</param>
        internal PairSocket(SocketBase socketHandle)
            : base(socketHandle)
        {
        }

        /// <summary>
        /// Create and return an inproc pipe where socket1 is bound and socket2 is connected.
        /// </summary>
        /// <param name="socket1">the Bind socket</param>
        /// <param name="socket2">the Connect socket</param>
        public static void CreateSocketPair(out PairSocket socket1, out PairSocket socket2)
        {
            string address = $"inproc://NetMQSocketPair#{Interlocked.Increment(ref s_sequence)}";

            socket1 = new PairSocket();
            socket1.Bind(address);

            socket2 = new PairSocket();
            socket2.Connect(address);
        }

        /// <summary>
        /// Create and return an inproc pipe where socket1 is bound and socket2 is connected.
        /// </summary>
        /// <param name="socket1">the Bind socket</param>
        /// <param name="socket2">the Connect socket</param>
        /// <param name="initSocket1">Method to initialize socket1 before connection</param>
        /// <param name="initSocket2">Method to initialize socket2 before connection</param>
        public static void CreateSocketPair(out PairSocket socket1, out PairSocket socket2, Action<PairSocket> initSocket1, Action<PairSocket> initSocket2)
        {
            string address = $"inproc://NetMQSocketPair#{Interlocked.Increment(ref s_sequence)}";

            socket1 = new PairSocket();
            initSocket1(socket1);
            socket1.Bind(address);

            socket2 = new PairSocket();
            initSocket2(socket2);
            socket2.Connect(address);
        }
    }
}