Class WriterThread

_pydevd_bundle/pydevd_comm.py:363–448

writer thread writes out the commands in an infinite loop

class WriterThread(PyDBDaemonThread):
    """writer thread writes out the commands in an infinite loop"""

    def __init__(self, sock, py_db, terminate_on_socket_close=True):
        PyDBDaemonThread.__init__(self, py_db)
        self.sock = sock
        self.__terminate_on_socket_close = terminate_on_socket_close
        self.name = "pydevd.Writer"
        self._cmd_queue = _queue.Queue()
        if pydevd_vm_type.get_vm_type() == "python":
            self.timeout = 0
        else:
            self.timeout = 0.1

    def add_command(self, cmd):
        """cmd is NetCommand"""
        if not self._kill_received:  # we don't take new data after everybody die
            self._cmd_queue.put(cmd, False)

    @overrides(PyDBDaemonThread._on_run)
    def _on_run(self):
        """just loop and write responses"""

        try:
            while True:
                try:
                    try:
                        cmd = self._cmd_queue.get(True, 0.1)
                    except _queue.Empty:
                        if self._kill_received:
                            pydev_log.debug("WriterThread: kill_received (sock.shutdown(SHUT_WR))")
                            try:
                                self.sock.shutdown(SHUT_WR)
                            except:
                                pass
                            # Note: don't close the socket, just send the shutdown,
                            # then, when no data is received on the reader, it can close
                            # the socket.
                            # See: https://blog.netherlabs.nl/articles/2009/01/18/the-ultimate-so_linger-page-or-why-is-my-tcp-not-reliable

                            # try:
                            #     self.sock.close()
                            # except:
                            #     pass

                            return  # break if queue is empty and _kill_received
                        else:
                            continue
                except:
                    # pydev_log.info('Finishing debug communication...(1)')
                    # when liberating the thread here, we could have errors because we were shutting down
                    # but the thread was still not liberated
                    return

                if cmd.as_dict is not None:
                    for listener in self.py_db.dap_messages_listeners:
                        listener.before_send(cmd.as_dict)