Streaming API
=============

Redshelf operates a streaming API which provides updates from our dynamic pricing system.  Please contact support if
you're interested in using a push stream.

Subscribe Method
----------------

To use the response body subscription method make a streaming request to the following URL:
`http://pubsub.redshelf.com:9080/sub/pricing/`

Long Polling Method
-------------------

To use the HTTP long polling method make a streaming request to the following URL:
`http://pubsub.redshelf.com:9080/lp/pricing/`

JSONP Method
------------

To use the JSONP method make a streaming request to the following URL:
`http://pubsub.redshelf.com:9080/jsonp/pricing/`

Websockets Method
-----------------

To use the websockets method make a streaming request to the following URL:
`http://pubsub.redshelf.com:9080/ws/pricing/`

Example Message
---------------

    Example pricing message::

        {
            "id":6,
            "channel":"pricing",
            "data":{
                        "book": "ccc5a093f5ee30ec749e4909840f0f7b794066bb",
                        "isbn": "123456789012",
                        "id": 123,
                        "new_price": 6.42,
                        "limit_days": 180
                   },
            "tag":"1",
            "time":"Thu, 05 Jun 2014 20:39:31 GMT",
        }


Example Long Polling Script
---------------------------

    This script provides a basic example of making long polling requests via requests.  It may not be ideal for production
    systems::

        import simplejson
        import requests
        s = requests.Session()


        def streaming():
            headers = {'connection': 'keep-alive', 'content-type': 'application/json',
                       'transfer-encoding': 'chunked'}

            req = requests.Request("GET", 'http://pubsub.redshelf.com:9080/lp/pricing/',
                                    headers=headers).prepare()
            resp = s.send(req, stream=True)

            for line in resp.iter_lines():
                if line:
                    yield line


        def read_stream():
            for line in streaming():
                print line

        while 1:
            try:
                print simplejson.loads(read_stream())
            except TypeError:
                continue