]>
Commit | Line | Data |
---|---|---|
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 | import sys, select, time | |
12 | ||
13 | from .api import TwitterCall, wrap_response, TwitterHTTPError | |
14 | ||
15 | def recv_chunk(sock): # -> bytearray: | |
16 | ||
17 | buf = sock.recv(8) # Scan for an up to 16MiB chunk size (0xffffff). | |
18 | crlf = buf.find(b'\r\n') # Find the HTTP chunk size. | |
19 | ||
20 | if crlf > 0: # If there is a length, then process it | |
21 | ||
22 | remaining = int(buf[:crlf], 16) # Decode the chunk size. | |
23 | ||
24 | start = crlf + 2 # Add in the length of the header's CRLF pair. | |
25 | end = len(buf) - start | |
26 | ||
27 | chunk = bytearray(remaining) | |
28 | ||
29 | if remaining <= 2: # E.g. an HTTP chunk with just a keep-alive delimiter. | |
30 | chunk[:remaining] = buf[start:start + remaining] | |
31 | # There are several edge cases (remaining == [3-6]) as the chunk size exceeds the length | |
32 | # of the initial read of 8 bytes. With Twitter, these do not, in practice, occur. The | |
33 | # shortest JSON message starts with '{"limit":{'. Hence, it exceeds in size the edge cases | |
34 | # and eliminates the need to address them. | |
35 | else: # There is more to read in the chunk. | |
36 | chunk[:end] = buf[start:] | |
37 | chunk[end:] = sock.recv(remaining - end) | |
38 | sock.recv(2) # Read the trailing CRLF pair. Throw it away. | |
39 | ||
40 | return chunk | |
41 | ||
42 | return bytearray() | |
43 | ||
44 | ## recv_chunk() | |
45 | ||
46 | ||
47 | class TwitterJSONIter(object): | |
48 | ||
49 | def __init__(self, handle, uri, arg_data, block=True, timeout=None): | |
50 | self.handle = handle | |
51 | self.uri = uri | |
52 | self.arg_data = arg_data | |
53 | self.block = block | |
54 | self.timeout = timeout | |
55 | ||
56 | ||
57 | def __iter__(self): | |
58 | sock = self.handle.fp.raw._sock if sys.version_info >= (3, 0) else self.handle.fp._sock.fp._sock | |
59 | sock.setsockopt(socket.SOL_SOCKET, socket.SO_KEEPALIVE, 1) | |
60 | sock.setblocking(self.block and not self.timeout) | |
61 | buf = u'' | |
62 | json_decoder = json.JSONDecoder() | |
63 | timer = time.time() | |
64 | while True: | |
65 | try: | |
66 | buf = buf.lstrip() | |
67 | res, ptr = json_decoder.raw_decode(buf) | |
68 | buf = buf[ptr:] | |
69 | yield wrap_response(res, self.handle.headers) | |
70 | timer = time.time() | |
71 | continue | |
72 | except ValueError as e: | |
73 | if self.block: pass | |
74 | else: yield None | |
75 | try: | |
76 | buf = buf.lstrip() # Remove any keep-alive delimiters to detect hangups. | |
77 | if self.timeout: | |
78 | ready_to_read = select.select([sock], [], [], self.timeout) | |
79 | if ready_to_read[0]: | |
80 | buf += recv_chunk(sock).decode('utf-8') # This is a non-blocking read. | |
81 | if time.time() - timer > self.timeout: | |
82 | yield {'timeout': True} | |
83 | else: yield {'timeout': True} | |
84 | else: | |
85 | buf += recv_chunk(sock).decode('utf-8') | |
86 | if not buf and self.block: | |
87 | yield {'hangup': True} | |
88 | except SSLError as e: | |
89 | # Error from a non-blocking read of an empty buffer. | |
90 | if (not self.block or self.timeout) and (e.errno == 2): pass | |
91 | else: raise | |
92 | ||
93 | def handle_stream_response(req, uri, arg_data, block, timeout=None): | |
94 | try: | |
95 | handle = urllib_request.urlopen(req,) | |
96 | except urllib_error.HTTPError as e: | |
97 | raise TwitterHTTPError(e, uri, 'json', arg_data) | |
98 | return iter(TwitterJSONIter(handle, uri, arg_data, block, timeout=timeout)) | |
99 | ||
100 | class TwitterStreamCallWithTimeout(TwitterCall): | |
101 | def _handle_response(self, req, uri, arg_data, _timeout=None): | |
102 | return handle_stream_response(req, uri, arg_data, block=True, timeout=self.timeout) | |
103 | ||
104 | class TwitterStreamCall(TwitterCall): | |
105 | def _handle_response(self, req, uri, arg_data, _timeout=None): | |
106 | return handle_stream_response(req, uri, arg_data, block=True) | |
107 | ||
108 | class TwitterStreamCallNonBlocking(TwitterCall): | |
109 | def _handle_response(self, req, uri, arg_data, _timeout=None): | |
110 | return handle_stream_response(req, uri, arg_data, block=False) | |
111 | ||
112 | class TwitterStream(TwitterStreamCall): | |
113 | """ | |
114 | The TwitterStream object is an interface to the Twitter Stream API | |
115 | (stream.twitter.com). This can be used pretty much the same as the | |
116 | Twitter class except the result of calling a method will be an | |
117 | iterator that yields objects decoded from the stream. For | |
118 | example:: | |
119 | ||
120 | twitter_stream = TwitterStream(auth=OAuth(...)) | |
121 | iterator = twitter_stream.statuses.sample() | |
122 | ||
123 | for tweet in iterator: | |
124 | ...do something with this tweet... | |
125 | ||
126 | The iterator will yield tweets forever and ever (until the stream | |
127 | breaks at which point it raises a TwitterHTTPError.) | |
128 | ||
129 | The `block` parameter controls if the stream is blocking. Default | |
130 | is blocking (True). When set to False, the iterator will | |
131 | occasionally yield None when there is no available message. | |
132 | """ | |
133 | def __init__( | |
134 | self, domain="stream.twitter.com", secure=True, auth=None, | |
135 | api_version='1.1', block=True, timeout=None): | |
136 | uriparts = () | |
137 | uriparts += (str(api_version),) | |
138 | ||
139 | if block: | |
140 | if timeout: | |
141 | call_cls = TwitterStreamCallWithTimeout | |
142 | else: | |
143 | call_cls = TwitterStreamCall | |
144 | else: | |
145 | call_cls = TwitterStreamCallNonBlocking | |
146 | ||
147 | TwitterStreamCall.__init__( | |
148 | self, auth=auth, format="json", domain=domain, | |
149 | callable_cls=call_cls, | |
150 | secure=secure, uriparts=uriparts, timeout=timeout, gzip=False) |