twitter/stream.py

   1 try:
   2     import urllib.request as urllib_request
   3     import urllib.error as urllib_error
   4     import io
   5 except ImportError:
   6     import urllib2 as urllib_request
   7     import urllib2 as urllib_error
   8 import json
   9 from ssl import SSLError
  10
  11 from .api import TwitterCall, wrap_response
  12
  13 class TwitterJSONIter(object):
  14
  15     def __init__(self, handle, uri, arg_data, block=True):
  16         self.decoder = json.JSONDecoder()
  17         self.handle = handle
  18         self.buf = b""
  19         self.block = block
  20
  21     def __iter__(self):
  22         sock = self.handle.fp._sock.fp._sock
  23         if not self.block:
  24             sock.setblocking(False)
  25         while True:
  26             try:
  27                 utf8_buf = self.buf.decode('utf8').lstrip()
  28                 res, ptr = self.decoder.raw_decode(utf8_buf)
  29                 self.buf = utf8_buf[ptr:].encode('utf8')
  30                 yield wrap_response(res, self.handle.headers)
  31                 continue
  32             except ValueError as e:
  33                 if self.block:
  34                     pass
  35                 else:
  36                     yield None
  37             except urllib_error.HTTPError as e:
  38                 raise TwitterHTTPError(e, uri, self.format, arg_data)
  39             # this is a non-blocking read (ie, it will return if any data is available)
  40             try:
  41                 self.buf += sock.recv(1024)
  42             except SSLError as e:
  43                 if (not self.block) and (e.errno == 2):
  44                     # Apparently this means there was nothing in the socket buf
  45                     pass
  46                 else:
  47                     raise
  48
  49 def handle_stream_response(req, uri, arg_data, block):
  50     handle = urllib_request.urlopen(req,)
  51     return iter(TwitterJSONIter(handle, uri, arg_data, block))
  52
  53 class TwitterStreamCall(TwitterCall):
  54     def _handle_response(self, req, uri, arg_data):
  55         return handle_stream_response(req, uri, arg_data, block=True)
  56
  57 class TwitterStreamCallNonBlocking(TwitterCall):
  58     def _handle_response(self, req, uri, arg_data):
  59         return handle_stream_response(req, uri, arg_data, block=False)
  60
  61 class TwitterStream(TwitterStreamCall):
  62     """
  63     The TwitterStream object is an interface to the Twitter Stream API
  64     (stream.twitter.com). This can be used pretty much the same as the
  65     Twitter class except the result of calling a method will be an
  66     iterator that yields objects decoded from the stream. For
  67     example::
  68
  69         twitter_stream = TwitterStream(auth=UserPassAuth('joe', 'joespassword'))
  70         iterator = twitter_stream.statuses.sample()
  71
  72         for tweet in iterator:
  73             ...do something with this tweet...
  74
  75     The iterator will yield tweets forever and ever (until the stream
  76     breaks at which point it raises a TwitterHTTPError.)
  77
  78     The `block` parameter controls if the stream is blocking. Default
  79     is blocking (True). When set to False, the iterator will
  80     occasionally yield None when there is no available message.
  81     """
  82     def __init__(
  83         self, domain="stream.twitter.com", secure=True, auth=None,
  84         api_version='1', block=True):
  85         uriparts = ()
  86         uriparts += (str(api_version),)
  87
  88         if block:
  89             call_cls = TwitterStreamCall
  90         else:
  91             call_cls = TwitterStreamCallNonBlocking
  92
  93         TwitterStreamCall.__init__(
  94             self, auth=auth, format="json", domain=domain,
  95             callable_cls=call_cls,
  96             secure=secure, uriparts=uriparts)