[Linphone-developers] 3rd Party Control / CSTA for linphone using JSON-RPC / ECMA-TR87

[Jos Huybrighs]

Hi,

 

During the last couple of weeks I added support to linphone to allow linphone to be controlled from a Web server.

 

I am aware of the 'console' interface that is available in linphone to base such implementation on but it nevertheless looked more logical to base my implementation on the ECMA CSTA approach (specified in TR-87). So I used that specification for laying out the format and data elements of the required request and notifications. However, pure TR-87 recommends the use of SIP INFO messages as transport layer for exchanging CSTA requests and notifications. This I find a bit of overkill on the Web server side, and therefore looked at the possibility to allow TR-87 CSTA requests and notifications to be simply exchanged as remote procedure calls between a web server and linphone. JSON-RPC looks like the most natural way to do this.

 

To make this happen with linphone I have created my own 'SIPUserAgent' application which consists of a small RPC server component, a CallControl component, the linphone library, and some helper components. The CallControl component sits between the RPC server and linphone. It implements the RPC method handlers and makes the bridge to linphone.

 

For the time being the RPC server assumes simple TCP as transport layer (which obviously requires that the RPC server listening port is accessible), but can be enhanced to also support HTTP.

Talking about 'pure' ECMA-TR87 the CallControl component could possibly later even also be enhanced to support requests/notifications using SIP INFO. Since I am not an expert in linphone itself I am not sure however how easy this would be (i.e. how to get the SIP INFO messages).

  

My question now: would someone be interested in what I have been doing. If so, how should I proceed with making my software available? Most of the work I did is written in C++ with linphone integrated as a library. Is there a place available on the linphone development site to put my source files on? Can it go in linphones development tree? Do I have to setup a web site myself?

 

Note: The application is currently targetting Windows but is designed to make abstraction of the underlying OS.

 

Thanks,

Jos