Incorporating Signal R into an already existing web application

Question

From my understanding, the beauty of signal R is that it takes care of the "handshake" between the client and server to determine the best form of communciation between them (websockets, long polling, etc). I understand that by default it does this at the /signalr route. I read that before this the handshake would be accomplished with an HTTP Get request with an Upgrade/Connection header specifying to upgrade to this new connection.

In my current application we support handling many HTTP requests in a RESTful manner. If we wanted to expose some of this data in real time rather than in this request response format, what would be the best way to determine if we should open a connection using signal R? Would checking for those headers still suffice? I just feel like that is a bit redundant since signal R abstracts that away.

Instead of this, would a solution be for the client to specifically invoke a hub method to kick off the streaming as soon as he connects to the proper endpoint?

TLDR: Need a way to open a signal R connection from a HTTP request, don't know the best way to go about that whether it be from requesting the resource with custom HTTP headers or by just navigating to the url resource and having their client invoke a hub method.

Answer 1

A typical example of using signalr is:

1. an html file using JavaScript to connect to a signalr Server when the page is loaded. we call this signalr client.

2. a signalr server written in c#. it can be a winform or console or service.

3. the signalr Server can call any dll, or webservices or webapi located in the same server, or even in different Server.

then, the client can call any function defined in the signalr server. the server can call any function defined in the client for a particular client or for groups of clients.

also, client x can call client y functions as well.

I would also suggest you create this index.html inside a Cordova project, so that your client can use this app using any pc desktop browser, or any mobile phone browser, or run it as an Android or iPhone native app, by using One set of client codes.

Answer 2

if they navigate to some url resource instead of receiving a response with json in its body we want them to be constantly in real time using signal r receiving data

I don't think this is possible with SignalR. Reason is that all SignaR communication is done through single route (xxx.xxx.xxx.xxx/signalR) + all SignaR connections are established using handshake (By client sending negotiate request to this route. Well maybe not all - not sure if negotiation is happening in case you initialize SignalR connection object with specific transport).