deb-python-autobahn/docs/index.rst

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Open-source (MIT) real-time framework for Web, Mobile & Internet of Things.

is part of the Autobahn project and provides open-source implementations of

• The WebSocket Protocol
• The Web Application Messaging Protocol (WAMP)

in Python 2 and 3, running on Twisted or asyncio.

Documentation Overview

See site_contents for a full site-map. Top-level pages available:

installation asynchronous-programming wamp/programming wamp/examples websocket/programming websocket/examples reference/autobahn contribute changelog

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Autobahn Features

WebSocket allows bidirectional real-time messaging on the Web while WAMP provides applications with high-level communication abstractions (remote procedure calling and publish/subscribe) in an open standard WebSocket-based protocol.

features:

• framework for WebSocket and WAMP clients
• compatible with Python 2.7 and 3.3+
• runs on CPython, PyPy and Jython
• runs under Twisted and asyncio
• implements WebSocket RFC6455 (and draft versions Hybi-10+)
• implements WebSocket compression
• implements WAMP, the Web Application Messaging Protocol
• supports TLS (secure WebSocket) and proxies
• Open-source (MIT license)

...and much more.

Further, is written with these goals:

1. high-performance, fully asynchronous and scalable code
2. best-in-class standards conformance and security

We do take those design and implementation goals quite serious. For example, has 100% strict passes with AutobahnTestsuite, the quasi industry standard of WebSocket protocol test suites we originally created only to test ;)

Note

In the following, we will just refer to instead of the more precise term and there is no ambiguity.

What can I do with Autobahn?

WebSocket is great for apps like chat, trading, multi-player games or real-time charts. It allows you to actively push information to clients as it happens. (See also run_all_examples)

Further, WebSocket allows you to real-time enable your Web user interfaces: always current information without reloads or polling. UIs no longer need to be a boring, static thing. Looking for the right communication technology for your next-generation Web apps? Enter WebSocket.

And WebSocket works great not only on the Web, but also as a protocol for wiring up the Internet-of-Things (IoT). Connecting a sensor or actor to other application components in real-time over an efficient protocol. Plus: you are using the same protocol to connect frontends like Web browsers.

While WebSocket already is quite awesome, it is still low-level. Which is why we have WAMP. WAMP allows you to compose your application from loosely coupled components that talk in real-time with each other - using nice high-level communication patterns ("Remote Procedure Calls" and "Publish & Subscribe").

WAMP enables application architectures with application code distributed freely across processes and devices according to functional aspects. Since WAMP implementations exist for multiple languages, WAMP applications can be polyglot. Application components can be implemented in a language and run on a device which best fit the particular use case.

WAMP is a routed protocol, so you need a WAMP router. We suggest using Crossbar.io, but there are also other implementations available.

More:

• WebSocket - Why, what, and - can I use it?
• Why WAMP?

Show me some code!

A sample WebSocket server:

from autobahn.twisted.websocket import WebSocketServerProtocol
# or: from autobahn.asyncio.websocket import WebSocketServerProtocol

    class MyServerProtocol(WebSocketServerProtocol):

       def onConnect(self, request):
           print("Client connecting: {}".format(request.peer))

       def onOpen(self):
           print("WebSocket connection open.")

       def onMessage(self, payload, isBinary):
           if isBinary:
               print("Binary message received: {} bytes".format(len(payload)))
           else:
               print("Text message received: {}".format(payload.decode('utf8')))

           ## echo back message verbatim
           self.sendMessage(payload, isBinary)

       def onClose(self, wasClean, code, reason):
           print("WebSocket connection closed: {}".format(reason))

Complete example code:

• WebSocket Echo (Twisted-based)
• WebSocket Echo (Asyncio-based)

Introduction to WebSocket Programming with :

• websocket/programming

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A sample WAMP application component implementing all client roles:

from autobahn.twisted.wamp import ApplicationSession
# or: from autobahn.asyncio.wamp import ApplicationSession
class MyComponent(ApplicationSession):

   @inlineCallbacks
   def onJoin(self, details):

       # 1) subscribe to a topic
       def onevent(msg):
           print("Got event: {}".format(msg))
       yield self.subscribe(onevent, 'com.myapp.hello')

       # 2) publish an event
       self.publish('com.myapp.hello', 'Hello, world!')

       # 3) register a procedure for remoting
       def add2(x, y):
           return x + y
       self.register(add2, 'com.myapp.add2');

       # 4) call a remote procedure
       res = yield self.call('com.myapp.add2', 2, 3)
       print("Got result: {}".format(res))

Complete example code:

• Twisted Example
• asyncio Example

Introduction to WAMP Programming with :

• wamp/programming

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Where to start

To get started, jump to installation.

For developers new to asynchronous programming, Twisted or asyncio, we've collected some useful pointers and information in asynchronous-programming.

For WebSocket developers, websocket/programming explains all you need to know about using as a WebSocket library, and includes a full reference for the relevant parts of the API.

websocket/examples lists WebSocket code examples covering a broader range of uses cases and advanced WebSocket features.

For WAMP developers, wamp/programming gives an introduction for programming with WAMP in Python using .

wamp/examples lists WAMP code examples covering all features of WAMP.

Community

Development of takes place on the GitHub source repository.

Note

We are open for contributions, whether that's code or documentation! Preferably via pull requests.

We also take bug reports at the issue tracker.

The best place to ask questions is on the mailing list. We'd also love to hear about your project and what you are using for!

Another option is StackOverflow where questions related to are tagged "autobahn" (or "autobahnws").

The best way to Search the Web for related material is by using these (base) search terms:

• "autobahnpython"
• "autobahnws"

You can also reach users and developers on IRC channel #autobahn at freenode.net.

Finally, we are on Twitter.

installation asynchronous-programming websocket/programming wamp/programming websocket/examples wamp/examples reference/autobahn contribute changelog