Deal with reading empty buffer (SSL errno2) in timeout mode

[z_archive/twitter.git] / twitter / stream.py

diff --git a/twitter/stream.py b/twitter/stream.py
index 5cb700892f804dd84b6c7b52ba8e04da83bb816b..83079d5779d7b532fe1e2a1f22f20912df805874 100644 (file)
--- a/twitter/stream.py
+++ b/twitter/stream.py
@@ -1,46 +1,122 @@
 try:
     import urllib.request as urllib_request
     import urllib.error as urllib_error
+    import io
 except ImportError:
     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
+from .api import TwitterCall, wrap_response, TwitterHTTPError
 
 class TwitterJSONIter(object):
 
-    def __init__(self, handle, uri, arg_data):
+    def __init__(self, handle, uri, arg_data, block=True, timeout=None):
         self.decoder = json.JSONDecoder()
         self.handle = handle
-        self.buf = ""
+        self.buf = b""
+        self.block = block
+        self.timeout = timeout
+        self.timer = time.time()
+
 
     def __iter__(self):
+        if sys.version_info >= (3, 0):
+            sock = self.handle.fp.raw._sock
+        else:
+            sock = self.handle.fp._sock.fp._sock
+        sock.setsockopt(socket.SOL_SOCKET, socket.SO_KEEPALIVE, 1)
+        if not self.block or self.timeout:
+            sock.setblocking(False)
         while True:
-            # This might need better py3 IO
-            self.buf += self.handle.read(1024).decode('utf8')
             try:
-                res, ptr = self.decoder.raw_decode(self.buf)
-                self.buf = self.buf[ptr + 2:] # +2 is for \r\n
+                utf8_buf = self.buf.decode('utf8').lstrip()
+                res, ptr = self.decoder.raw_decode(utf8_buf)
+                self.buf = utf8_buf[ptr:].encode('utf8')
                 yield wrap_response(res, self.handle.headers)
-            except ValueError as e:
+                self.timer = time.time()
                 continue
+            except ValueError as e:
+                if self.block:
+                    pass
+                else:
+                    yield None
             except urllib_error.HTTPError as e:
                 raise TwitterHTTPError(e, uri, self.format, arg_data)
+            # this is a non-blocking read (ie, it will return if any data is available)
+            try:
+                if self.timeout:
+                    ready_to_read = select.select([sock], [], [], self.timeout)
+                    if ready_to_read[0]:
+                        self.buf += sock.recv(1024)
+                        if time.time() - self.timer > self.timeout:
+                            yield {"timeout":True}
+                    else:
+                        yield {"timeout":True}
+                else:
+                    self.buf += sock.recv(1024)
+            except SSLError as e:
+                if (not self.block or self.timeout) and (e.errno == 2):
+                    # Apparently this means there was nothing in the socket buf
+                    pass
+                else:
+                    raise
+
+def handle_stream_response(req, uri, arg_data, block, timeout=None):
+    handle = urllib_request.urlopen(req,)
+    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):
-        handle = urllib_request.urlopen(req,)
-        return iter(TwitterJSONIter(handle, uri, arg_data))
+    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):
+    """
+    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=OAuth(...))
+        iterator = twitter_stream.statuses.sample()
+
+        for tweet in iterator:
+            ...do something with this tweet...
+
+    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=False, auth=None,
-        api_version='1'):
+        self, domain="stream.twitter.com", secure=True, auth=None,
+        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)