Crossbar HTTP

Module that provides methods for accessing Crossbar.io HTTP Bridge Services

Revision History

• v0.1.2:
  • Added "ClientCallRuntimeError" exception for general errors
• v0.1.1:
  • Added class defined Exceptions for specific events
  • Added key/secret handling
• v0.1:
  • Initial version

Installation

pip install crossbarhttp

Usage

Call

To call a Crossbar HTTP bridge, do the following

client = Client("http://127.0.0.1/call")
result = client.call("com.example.add", 2, 3, offset=10)

This will call the following method

def onJoin(self, details):

    def add_something(x, y, offset=0):
        print "Add was called"
        return x+y+offset

    self.register(add_something, "com.example.add")

Publish

To publish to a Crossbar HTTP bridge, do the following

client = Client("http://127.0.0.1/publish")
result = client.publish("com.example.event", event="new event")

The receiving subscription would look like

def onJoin(self, details):

    def subscribe_something(event=None, **kwargs):
        print "Publish was called with event %s" % event

    self.subscribe(subscribe_something, "com.example.event") 

Key/Secret

For bridge services that have a key and secret defined, simply include the key and secret in the instantiation of the client.

client = Client("http://127.0.0.1/publish", key="key", secret="secret")

Exceptions

The library will throw the following exceptions. Note that all exceptions subclass from "ClientBaseException" so you can just catch that if you don't want the granularity.

• ClientBadUrl - The specified URL is not a HTTP bridge service
• ClientBadHost - The specified host name is rejecting the connection
• ClientMissingParams - The call was missing parameters
• ClientSignatureError - The signature did not match
• ClientNoCalleeRegistered - Callee was not registered on the router for the specified procedure
• ClientCallRuntimeError - Procedure triggered an exception

Contributing

To contribute, fork the repo and submit a pull request.

Testing

The test can be run by using Docker Compose. Connect to a docker host and type

%> docker-compose build
%> docker-compose up

The Docker Compose file creates a generic router with an example service connected to it and runs the tests.

The service "crossbarhttp_test_1" will return a 0 value if the tests were successful and non zero otherwise. To get the pass/fail results from a command line, do the following

#!/usr/bin/env bash

docker-compose build
docker-compose up

exit $(docker-compose ps -q | xargs docker inspect -f '{{ .Name }} exited with status {{ .State.ExitCode }}' | grep test_1 | cut -f5 -d ' ')

This is a little hacky (and hopefully Docker will fix it) but it will do the trick for now.

License

MIT