Pygrunn: Python, WebRTC and You - Saúl Ibarra Corretgé¶

Tags: pygrunn, python, django

(One of the summaries of the 2015 Pygrunn conference )

Saúl Ibarra Corretgé does telecom and VOIP stuff for his work, which is what webRTC calls legacy :-)

webRTC is Real-Time Communication for the web via simple APIs. So: voice calling, video chat, P2P file sharing without needing internal or external plugins.

Basically it is a big pile of C++ that sits in your browser. One of the implementations is http://www.webrtc.org/. Some people say that webRTC stand for Well, Everybody Better Restart Their Chrome. Because the browser support is mostly limited to chrome. There’s a plugin for IE/safari, though.

There are several javascript libraries for webRTC. They help you set up a secure connection to another person (a “RTCPeerConnection”). The connection is directly, if possible. If not, due to firewalls for instance, you can use an external server. It uses ICE, which means Interactive Connectivity Establishment (see ICE trickle which he apparently used). A way to set up the connection.

Once you have a connection, you have an RTCDataChannel. Which you can use, for instance, to send a file from one browser to another.

As a testcase, he wrote Call Roulette. The app is in python, but in the browser javascript is used as that is more-or-less the native way to do it. The “call roulette” app connects a user to a random other user. Users will send simple json requests to the app. Once the app finds two candidates, both get the other’s data to set up a subsequent webRTC connection.

He made the toy app in python 3.3 because it is new. It has websockets. And async via asyncio “because async is modern :-)”. All, nice new and shiny.

So: users connect from their browser with a websocket connection to the app. They are paired up and the webRTC connection data is send back. Very fast.

Fun: light-weight django-models-like models via https://pypi.python.org/pypi/jsonmodels/ ! Look it up.

He did a live demo with web video with someone from the audience. Worked basically like a charm.