PersistentConnection

Persistent Connections

A PersistentConnection is an IHttpHandler that has an api for exposing a SignalR service over http.

To create a new endpoint. Create a new class that derives from PersistentConnection.

public class MyEndPoint : PersistentConnection 
{
}

To make this endpoint accessible, add a route to Application_Start (or something similar):

using SignalR.Routing;

public void Application_Start() {
    RouteTable.Routes.MapConnecton<MyEndPoint>("echo", "echo/{*operation}");
}

This will expose make /echo a SignalR endpoint.

PersistentConnection API

Task PersistentConnection.OnConnectedAsync(HttpContextBase context, string clientId)

Called when a new connection is made.

• context - The HttpContext associated with this connection.
• clientId - The client id of the new connection.
• NOTE: You can use OnConnected if you just want to do synchronous work and not have to return a Task.

Example

public class MyEndPoint : PersistentConnection 
{
    protected override Task OnConnectedAsync(HttpContextBase context, string clientId)
    {
        Connection.Broadcast("Client " + clientId + " connected");
    }
}

Task PersistentConnection.OnReceivedAsync(string clientId, string data)

Called when data is received from on the connection.

• clientId - The id of the client that sent the data
• data - The payload received from the client
• NOTE: You can use OnReceived if you just want to do synchronous work and not have to return a Task.

Example

public class MyEndPoint : PersistentConnection 
{
    protected override Task OnReceivedAsync(string clientId, string data) 
    {
        Connection.Broadcast("Client " + clientId + " sent " + data);   
    }
}

Task PersistentConnection.OnDisconnectAsync(string clientId)

Called when data is received from on the connection.

• clientId - The id of the client that disconnected
• NOTE: You can use OnDisconnect if you just want to do synchronous work and not have to return a Task.

Example

public class MyEndPoint : PersistentConnection 
{
    protected override Task OnDisconnectAsync(string clientId) 
    {
        Connection.Broadcast("Client " + clientId + " disconncted");   
    }
}

Task PersistentConnection.Send(string clientId, object value)

Sends a message to a specified client.

• clientId - Client id to send the message to
• data - The payload to send
• NOTE: Objects will be JSON serialized

Example

public class MyEndPoint : PersistentConnection 
{
    protected override Task OnReceivedAsync(string clientId, string data) 
    {
        return Send(clientId, data);   
    }
}

Task PersistentConnection.AddToGroup(string clientId, string groupName)

Adds a client to a specified group.

• clientId - client id to add to the group
• groupName - name of the group to add the client to
• NOTE: The task returned from this method does not mean the client was successfully added to the group.

Example

public class MyEndPoint : PersistentConnection 
{
    protected override Task OnReceivedAsync(string clientId, string data) 
    {
        return AddToGroup(clientId, "foo");   
    }
}

Task PersistentConnection.RemoveFromGroup(string clientId, string groupName)

Removes a client from a specified group.

• clientId - client id to remove from the group
• groupName - name of the group to remove the client from
• NOTE: The task returned from this method does not mean the client was successfully added to the group.

Example

public class MyEndPoint : PersistentConnection 
{
    protected override Task OnReceivedAsync(string clientId, string data) 
    {
        return RemoveFromGroup(clientId, "foo");   
    }
}

Task PersistentConnection.SendToGroup(string groupName, object value)

Sends a message to a specified group.

• groupName - name of the group to send the message to
• value - The payload to send
• NOTE: Objects will be JSON serialized

Example

public class MyEndPoint : PersistentConnection 
{
    protected override Task OnReceivedAsync(string clientId, string data) 
    {
        return SendToGroup("foo", data);   
    }
}

IConnection PersistentConnection.Connection

• Gets the IConnection for this PersistentConnection.