import urllib2 as urllib_request
import urllib2 as urllib_error
import json
+from ssl import SSLError
+import socket
+import sys, select, time
+
+from .api import TwitterCall, wrap_response, TwitterHTTPError
+
+python27_3 = sys.version_info >= (2, 7)
+def recv_chunk(sock): # -> bytearray:
+
+ header = sock.recv(8) # Scan for an up to 16MiB chunk size (0xffffff).
+ crlf = header.find(b'\r\n') # Find the HTTP chunk size.
+
+ if crlf > 0: # If there is a length, then process it
+
+ size = int(header[:crlf], 16) # Decode the chunk size. Rarely exceeds 8KiB.
+ chunk = bytearray(size)
+ start = crlf + 2 # Add in the length of the header's CRLF pair.
+
+ if size <= 3: # E.g. an HTTP chunk with just a keep-alive delimiter or end of stream (0).
+ chunk[:size] = header[start:start + size]
+ # There are several edge cases (size == [4-6]) as the chunk size exceeds the length
+ # of the initial read of 8 bytes. With Twitter, these do not, in practice, occur. The
+ # shortest JSON message starts with '{"limit":{'. Hence, it exceeds in size the edge cases
+ # and eliminates the need to address them.
+ else: # There is more to read in the chunk.
+ end = len(header) - start
+ chunk[:end] = header[start:]
+ if python27_3: # When possible, use less memory by reading directly into the buffer.
+ buffer = memoryview(chunk)[end:] # Create a view into the bytearray to hold the rest of the chunk.
+ sock.recv_into(buffer)
+ else: # less efficient for python2.6 compatibility
+ chunk[end:] = sock.recv(max(0, size - end))
+ sock.recv(2) # Read the trailing CRLF pair. Throw it away.
+
+ return chunk
+
+ return bytearray()
-from .api import TwitterCall, wrap_response
class TwitterJSONIter(object):
- def __init__(self, handle, uri, arg_data):
- self.decoder = json.JSONDecoder()
+ def __init__(self, handle, uri, arg_data, block=True, timeout=None):
self.handle = handle
- self.buf = b""
+ self.uri = uri
+ self.arg_data = arg_data
+ self.block = block
+ self.timeout = timeout
+
def __iter__(self):
+ sock = self.handle.fp.raw._sock if sys.version_info >= (3, 0) else self.handle.fp._sock.fp._sock
+ sock.setsockopt(socket.SOL_SOCKET, socket.SO_KEEPALIVE, 1)
+ sock.setblocking(self.block and not self.timeout)
+ buf = ''
+ json_decoder = json.JSONDecoder()
+ timer = time.time()
while True:
- # this is a non-blocking read (ie, it will return if any data is available)
- self.buf += self.handle.fp._sock.fp._sock.recv(1024)
try:
- utf8_buf = self.buf.decode('utf8').lstrip()
- res, ptr = self.decoder.raw_decode(utf8_buf)
- self.buf = utf8_buf[ptr:].encode('utf8')
+ buf = buf.lstrip()
+ res, ptr = json_decoder.raw_decode(buf)
+ buf = buf[ptr:]
yield wrap_response(res, self.handle.headers)
- except ValueError as e:
continue
- except urllib_error.HTTPError as e:
- raise TwitterHTTPError(e, uri, self.format, arg_data)
+ except ValueError as e:
+ if self.block: pass
+ else: yield None
+ try:
+ buf = buf.lstrip() # Remove any keep-alive delimiters to detect hangups.
+ if self.timeout and not buf: # This is a non-blocking read.
+ ready_to_read = select.select([sock], [], [], self.timeout)
+ if not ready_to_read[0] and time.time() - timer > self.timeout:
+ yield {'timeout': True}
+ continue
+ timer = time.time()
+ buf += recv_chunk(sock).decode('utf-8')
+ if not buf:
+ yield {'hangup': True}
+ break
+ except SSLError as e:
+ # Error from a non-blocking read of an empty buffer.
+ if (not self.block or self.timeout) and (e.errno == 2): pass
+ else: raise
-class TwitterStreamCall(TwitterCall):
- def _handle_response(self, req, uri, arg_data):
+def handle_stream_response(req, uri, arg_data, block, timeout=None):
+ try:
handle = urllib_request.urlopen(req,)
- return iter(TwitterJSONIter(handle, uri, arg_data))
+ except urllib_error.HTTPError as e:
+ raise TwitterHTTPError(e, uri, 'json', arg_data)
+ return iter(TwitterJSONIter(handle, uri, arg_data, block, timeout=timeout))
+
+class TwitterStreamCallWithTimeout(TwitterCall):
+ def _handle_response(self, req, uri, arg_data, _timeout=None):
+ return handle_stream_response(req, uri, arg_data, block=True, timeout=self.timeout)
+
+class TwitterStreamCall(TwitterCall):
+ def _handle_response(self, req, uri, arg_data, _timeout=None):
+ return handle_stream_response(req, uri, arg_data, block=True)
+
+class TwitterStreamCallNonBlocking(TwitterCall):
+ def _handle_response(self, req, uri, arg_data, _timeout=None):
+ return handle_stream_response(req, uri, arg_data, block=False)
class TwitterStream(TwitterStreamCall):
"""
- Interface to the Twitter Stream API (stream.twitter.com). This can
- be used pretty much the same as the Twitter class except the
- result of calling a method will be an iterator that yields objects
- decoded from the stream. For example::
+ The TwitterStream object is an interface to the Twitter Stream API
+ (stream.twitter.com). This can be used pretty much the same as the
+ Twitter class except the result of calling a method will be an
+ iterator that yields objects decoded from the stream. For
+ example::
- twitter_stream = TwitterStream(auth=UserPassAuth('joe', 'joespassword'))
+ twitter_stream = TwitterStream(auth=OAuth(...))
iterator = twitter_stream.statuses.sample()
for tweet in iterator:
The iterator will yield tweets forever and ever (until the stream
breaks at which point it raises a TwitterHTTPError.)
+
+ The `block` parameter controls if the stream is blocking. Default
+ is blocking (True). When set to False, the iterator will
+ occasionally yield None when there is no available message.
"""
def __init__(
self, domain="stream.twitter.com", secure=True, auth=None,
- api_version='1'):
+ api_version='1.1', block=True, timeout=None):
uriparts = ()
uriparts += (str(api_version),)
+ if block:
+ if timeout:
+ call_cls = TwitterStreamCallWithTimeout
+ else:
+ call_cls = TwitterStreamCall
+ else:
+ call_cls = TwitterStreamCallNonBlocking
+
TwitterStreamCall.__init__(
self, auth=auth, format="json", domain=domain,
- callable_cls=TwitterStreamCall,
- secure=secure, uriparts=uriparts)
+ callable_cls=call_cls,
+ secure=secure, uriparts=uriparts, timeout=timeout, gzip=False)