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Diffstat (limited to 'Lib/asyncio/transports.py')
-rw-r--r-- | Lib/asyncio/transports.py | 186 |
1 files changed, 186 insertions, 0 deletions
diff --git a/Lib/asyncio/transports.py b/Lib/asyncio/transports.py new file mode 100644 index 00000000000..bf3adee73a4 --- /dev/null +++ b/Lib/asyncio/transports.py @@ -0,0 +1,186 @@ +"""Abstract Transport class.""" + +__all__ = ['ReadTransport', 'WriteTransport', 'Transport'] + + +class BaseTransport: + """Base ABC for transports.""" + + def __init__(self, extra=None): + if extra is None: + extra = {} + self._extra = extra + + def get_extra_info(self, name, default=None): + """Get optional transport information.""" + return self._extra.get(name, default) + + def close(self): + """Closes the transport. + + Buffered data will be flushed asynchronously. No more data + will be received. After all buffered data is flushed, the + protocol's connection_lost() method will (eventually) called + with None as its argument. + """ + raise NotImplementedError + + +class ReadTransport(BaseTransport): + """ABC for read-only transports.""" + + def pause(self): + """Pause the receiving end. + + No data will be passed to the protocol's data_received() + method until resume() is called. + """ + raise NotImplementedError + + def resume(self): + """Resume the receiving end. + + Data received will once again be passed to the protocol's + data_received() method. + """ + raise NotImplementedError + + +class WriteTransport(BaseTransport): + """ABC for write-only transports.""" + + def write(self, data): + """Write some data bytes to the transport. + + This does not block; it buffers the data and arranges for it + to be sent out asynchronously. + """ + raise NotImplementedError + + def writelines(self, list_of_data): + """Write a list (or any iterable) of data bytes to the transport. + + The default implementation just calls write() for each item in + the list/iterable. + """ + for data in list_of_data: + self.write(data) + + def write_eof(self): + """Closes the write end after flushing buffered data. + + (This is like typing ^D into a UNIX program reading from stdin.) + + Data may still be received. + """ + raise NotImplementedError + + def can_write_eof(self): + """Return True if this protocol supports write_eof(), False if not.""" + raise NotImplementedError + + def abort(self): + """Closes the transport immediately. + + Buffered data will be lost. No more data will be received. + The protocol's connection_lost() method will (eventually) be + called with None as its argument. + """ + raise NotImplementedError + + +class Transport(ReadTransport, WriteTransport): + """ABC representing a bidirectional transport. + + There may be several implementations, but typically, the user does + not implement new transports; rather, the platform provides some + useful transports that are implemented using the platform's best + practices. + + The user never instantiates a transport directly; they call a + utility function, passing it a protocol factory and other + information necessary to create the transport and protocol. (E.g. + EventLoop.create_connection() or EventLoop.create_server().) + + The utility function will asynchronously create a transport and a + protocol and hook them up by calling the protocol's + connection_made() method, passing it the transport. + + The implementation here raises NotImplemented for every method + except writelines(), which calls write() in a loop. + """ + + +class DatagramTransport(BaseTransport): + """ABC for datagram (UDP) transports.""" + + def sendto(self, data, addr=None): + """Send data to the transport. + + This does not block; it buffers the data and arranges for it + to be sent out asynchronously. + addr is target socket address. + If addr is None use target address pointed on transport creation. + """ + raise NotImplementedError + + def abort(self): + """Closes the transport immediately. + + Buffered data will be lost. No more data will be received. + The protocol's connection_lost() method will (eventually) be + called with None as its argument. + """ + raise NotImplementedError + + +class SubprocessTransport(BaseTransport): + + def get_pid(self): + """Get subprocess id.""" + raise NotImplementedError + + def get_returncode(self): + """Get subprocess returncode. + + See also + http://docs.python.org/3/library/subprocess#subprocess.Popen.returncode + """ + raise NotImplementedError + + def get_pipe_transport(self, fd): + """Get transport for pipe with number fd.""" + raise NotImplementedError + + def send_signal(self, signal): + """Send signal to subprocess. + + See also: + docs.python.org/3/library/subprocess#subprocess.Popen.send_signal + """ + raise NotImplementedError + + def terminate(self): + """Stop the subprocess. + + Alias for close() method. + + On Posix OSs the method sends SIGTERM to the subprocess. + On Windows the Win32 API function TerminateProcess() + is called to stop the subprocess. + + See also: + http://docs.python.org/3/library/subprocess#subprocess.Popen.terminate + """ + raise NotImplementedError + + def kill(self): + """Kill the subprocess. + + On Posix OSs the function sends SIGKILL to the subprocess. + On Windows kill() is an alias for terminate(). + + See also: + http://docs.python.org/3/library/subprocess#subprocess.Popen.kill + """ + raise NotImplementedError |