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