Esempio n. 1
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    def __init__(self, server, sock, addr, adj, map=None):
        self.server = server
        self.adj = adj
        self.outbufs = [OverflowableBuffer(adj.outbuf_overflow)]
        self.creation_time = self.last_activity = time.time()

        # task_lock used to push/pop requests
        self.task_lock = thread.allocate_lock()
        # outbuf_lock used to access any outbuf
        self.outbuf_lock = thread.allocate_lock()

        asyncore.dispatcher.__init__(self, sock, map=map)

        # Don't let asyncore.dispatcher throttle self.addr on us.
        self.addr = addr
Esempio n. 2
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    def __init__(
        self,
        server,
        sock,
        addr,
        adj,
        map=None,
    ):
        self.server = server
        self.addr = addr
        self.adj = adj
        self.outbufs = [OverflowableBuffer(adj.outbuf_overflow)]
        self.creation_time = self.last_activity = time.time()

        # task_lock used to push/pop requests
        self.task_lock = thread.allocate_lock()
        # outbuf_lock used to access any outbuf
        self.outbuf_lock = thread.allocate_lock()

        asyncore.dispatcher.__init__(self, sock, map=map)
Esempio n. 3
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    def __init__(self):
        self._closed = False

        # `lock` protects the `thunks` list from being traversed and
        # appended to simultaneously.
        self.lock = thread.allocate_lock()

        # List of no-argument callbacks to invoke when the trigger is
        # pulled.  These run in the thread running the asyncore mainloop,
        # regardless of which thread pulls the trigger.
        self.thunks = []
Esempio n. 4
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 def __init__(self):
     self.threads = {} # { thread number -> 1 }
     self.queue = Queue()
     self.thread_mgmt_lock = thread.allocate_lock()
Esempio n. 5
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class HTTPChannel(logging_dispatcher, object):
    """Channel that switches between asynchronous and synchronous mode.

    Set self.requests = [somerequest] before using a channel in a thread other
    than the thread handling the main loop.

    Set self.requests = [] to give the channel back to the thread handling
    the main loop.
    """
    task_class = WSGITask
    error_task_class = ErrorTask
    parser_class = HTTPRequestParser

    request = None  # A request parser instance
    last_activity = 0  # Time of last activity
    will_close = False  # set to True to close the socket.
    requests = ()  # currently pending requests
    sent_continue = False  # used as a latch after sending 100 continue
    task_lock = thread.allocate_lock()  # lock used to push/pop requests
    force_flush = False  # indicates a need to flush the outbuf

    #
    # ASYNCHRONOUS METHODS (including __init__)
    #

    def __init__(
        self,
        server,
        sock,
        addr,
        adj,
        map=None,
    ):
        self.server = server
        self.addr = addr
        self.adj = adj
        self.outbuf = OverflowableBuffer(adj.outbuf_overflow)
        self.creation_time = self.last_activity = time.time()
        asyncore.dispatcher.__init__(self, sock, map=map)

    def writable(self):
        # if there's data in the out buffer or we've been instructed to close
        # the channel (possibly by our server maintenance logic), run
        # handle_write
        return bool(self.outbuf) or self.will_close

    def handle_write(self):
        # Precondition: there's data in the out buffer to be sent, or
        # there's a pending will_close request
        if not self.connected:
            # we dont want to close the channel twice
            return

        # try to flush any pending output
        if not self.requests:
            # 1. There are no running tasks, so we don't need to try to lock
            #    the outbuf before sending
            # 2. The data in the out buffer should be sent as soon as possible
            #    because it's either data left over from task output
            #    or a 100 Continue line sent within "received".
            flush = self._flush_some
        elif self.force_flush:
            # 1. There's a running task, so we need to try to lock
            #    the outbuf before sending
            # 2. This is the last chunk sent by the Nth of M tasks in a
            #    sequence on this channel, so flush it regardless of whether
            #    it's >= self.adj.send_bytes.  We need to do this now, or it
            #    won't get done.
            flush = self._flush_some_if_lockable
            self.force_flush = False
        elif (len(self.outbuf) >= self.adj.send_bytes):
            # 1. There's a running task, so we need to try to lock
            #    the outbuf before sending
            # 2. Only try to send if the data in the out buffer is larger
            #    than self.adj_bytes to avoid TCP fragmentation
            flush = self._flush_some_if_lockable
            self.force_flush = False
        else:
            # 1. There's not enough data in the out buffer to bother to send
            #    right now.
            flush = None

        if flush:
            try:
                flush()
            except socket.error:
                if self.adj.log_socket_errors:
                    self.logger.exception('Socket error')
                self.will_close = True

        if self.will_close:
            self.handle_close()

    def readable(self):
        # We might want to create a new task.  We can only do this if:
        # 1. We're not already about to close the connection.
        # 2. There's no already currently running task(s).
        # 3. There's no data in the output buffer that needs to be sent
        #    before we potentially create a new task.
        return not (self.will_close or self.requests or self.outbuf)

    def handle_read(self):
        try:
            data = self.recv(self.adj.recv_bytes)
        except socket.error:
            if self.adj.log_socket_errors:
                self.logger.exception('Socket error')
            self.handle_close()
            return
        if data:
            self.last_activity = time.time()
            self.received(data)

    def received(self, data):
        """
        Receives input asynchronously and assigns a task to the channel.
        """
        # Preconditions: there's no task(s) already running
        request = self.request
        requests = []

        if not data:
            return False

        while data:
            if request is None:
                request = self.parser_class(self.adj)
            n = request.received(data)
            if request.expect_continue and request.headers_finished:
                # guaranteed by parser to be a 1.1 request
                request.expect_continue = False
                if not self.sent_continue:
                    # there's no current task, so we don't need to try to
                    # lock the outbuf to append to it.
                    self.outbuf.append(b'HTTP/1.1 100 Continue\r\n\r\n')
                    self.sent_expect_continue = True
                    self._flush_some()
                    request.completed = False
            if request.completed:
                # The request (with the body) is ready to use.
                self.request = None
                if not request.empty:
                    requests.append(request)
                request = None
            else:
                self.request = request
            if n >= len(data):
                break
            data = data[n:]

        if requests:
            self.requests = requests
            self.server.add_task(self)

        return True

    def _flush_some_if_lockable(self):
        # Since our task may be appending to the outbuf, we try to acquire
        # the lock, but we don't block if we can't.
        outbuf = self.outbuf
        locked = outbuf.lock.acquire(0)
        if locked:
            try:
                self._flush_some()
            finally:
                outbuf.lock.release()

    def _flush_some(self):
        # Send as much data as possible to our client
        outbuf = self.outbuf
        outbuflen = len(outbuf)
        sent = 0
        while outbuflen > 0:
            chunk = outbuf.get(self.adj.send_bytes)
            num_sent = self.send(chunk)
            if num_sent:
                outbuf.skip(num_sent, True)
                outbuflen -= num_sent
                sent += num_sent
            else:
                break
        if sent:
            self.last_activity = time.time()
            return True
        return False

    def handle_close(self):
        self.connected = False
        asyncore.dispatcher.close(self)

    def add_channel(self, map=None):
        """See asyncore.dispatcher

        This hook keeps track of opened channels.
        """
        asyncore.dispatcher.add_channel(self, map)
        self.server.active_channels[self._fileno] = self

    def del_channel(self, map=None):
        """See asyncore.dispatcher

        This hook keeps track of closed channels.
        """
        fd = self._fileno  # next line sets this to None
        asyncore.dispatcher.del_channel(self, map)
        ac = self.server.active_channels
        if fd in ac:
            del ac[fd]

    #
    # SYNCHRONOUS METHODS
    #

    def write_soon(self, data):
        if data:
            # the async mainloop might be popping data off outbuf; we can
            # block here waiting for it because we're in a thread
            with self.outbuf.lock:
                self.outbuf.append(data)
            # XXX We might eventually need to pull the trigger here (to
            # instruct select to stop blocking), but it slows things down so
            # much that I'll hold off for now; "server push" on otherwise
            # unbusy systems may suffer.
            return len(data)
        return 0

    def service(self):
        """Execute all pending requests """
        with self.task_lock:
            while self.requests:
                request = self.requests[0]
                if request.error:
                    task = self.error_task_class(self, request)
                else:
                    task = self.task_class(self, request)
                try:
                    task.service()
                except:
                    self.logger.exception('Exception when serving %s' %
                                          task.request.path)
                    if not task.wrote_header:
                        if self.adj.expose_tracebacks:
                            body = traceback.format_exc()
                        else:
                            body = ('The server encountered an unexpected '
                                    'internal server error')
                        request = self.parser_class(self.adj)
                        request.error = InternalServerError(body)
                        task = self.error_task_class(self, request)
                        task.service()  # must not fail
                    else:
                        task.close_on_finish = True
                # we cannot allow self.requests to drop to empty til
                # here; otherwise the mainloop gets confused
                if task.close_on_finish:
                    self.will_close = True
                    self.requests = []
                else:
                    self.requests.pop(0)

        self.force_flush = True
        self.server.pull_trigger()
        self.last_activity = time.time()

    def cancel(self):
        """ Cancels all pending requests """
        self.force_flush = True
        self.last_activity = time.time()
        self.requests = []

    def defer(self):
        pass
Esempio n. 6
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 def __init__(self):
     self.threads = {}  # { thread number -> 1 }
     self.queue = Queue()
     self.thread_mgmt_lock = thread.allocate_lock()
Esempio n. 7
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 def __init__(self, overflow):
     # overflow is the maximum to be stored in a StringIO buffer.
     self.overflow = overflow
     self.lock = thread.allocate_lock() # API
Esempio n. 8
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 def __init__(self, overflow):
     # overflow is the maximum to be stored in a StringIO buffer.
     self.overflow = overflow
     self.lock = thread.allocate_lock()  # API