import threading
-def recv_loop(socket, urwid_pipe_write_fd, server_output):
- """Loop to receive messages from socket and deliver them to urwid.
-
- The message transfer to urwid is a bit weird. The urwid developers warn
- against sharing urwid resources among threads, and recommend using urwid's
- watch_pipe mechanism: using a pipe from non-urwid threads into a single
- urwid thread. We could pipe socket.recv output directly, but then we get
- complicated buffering situations here as well as in the urwid code that
- receives the pipe content. It's much easier to update a third resource
- (server_output, which references an object that's also known to the urwid
- code) to contain the new message, and then just use the urwid pipe
- (urwid_pipe_write_fd) to trigger the urwid code to pull the message in from
- that third resource. We send a single b' ' through the pipe to trigger it.
- """
- import os
- for msg in plom_socket_io.recv(socket):
- server_output[0] = msg
- os.write(urwid_pipe_write_fd, b' ')
-
-
-class InputHandler:
- """Helps delivering data from other thread to widget via message_container.
-
- The whole class only exists to provide handle_input as a bound method, with
- widget and message_container pre-set, as (bound) handle_input is used as a
- callback in urwid's watch_pipe – which merely provides its callback target
- with one parameter for a pipe to read data from an urwid-external thread.
- """
-
- def __init__(self, widget, message_container):
- self.widget = widget
- self.message_container = message_container
-
- def handle_input(self, trigger):
- """On input from other thread, either quit, or write to widget text.
-
- Serves as a receiver to urwid's watch_pipe mechanism, with trigger the
- data that a pipe defined by watch_pipe delivers. To avoid buffering
- trouble, we don't care for that data beyond the fact that its receival
- triggers this function: The sender is to write the data it wants to
- deliver into the container referenced by self.message_container, and
- just pipe the trigger to inform us about this.
-
- If the message delivered is 'BYE', quits Urbit.
+class UrwidSetup():
+
+ def __init__(self, socket):
+ """Build client urwid interface around socket communication.
+
+ Sets up all widgets for writing to the socket and representing data
+ from it. Sending via a self.EditToSocket widget is straightforward;
+ polling the socket for input from the server in parallel to the urwid
+ main loop not so much:
+
+ The urwid developers warn against sharing urwid resources among
+ threads, so having a socket polling thread for writing to an urwid
+ widget while other widgets are handled in other threads would be
+ dangerous. Urwid developers recommend using urwid's watch_pipe
+ mechanism instead: using a pipe from non-urwid threads into a single
+ urwid thread. We use self.recv_loop_thread to poll the socket, therein
+ write socket.recv output to an object that is then linked to by
+ self.server_output (which is known the urwid thread), and then use the
+ pipe to urwid to trigger it pulling new data from self.server_output to
+ handle via self.InputHandler. (We *could* pipe socket.recv output
+ directly, but then we get complicated buffering situations here as well
+ as in the urwid code that receives the pipe output. It's much easier to
+ just tell the urwid code where it finds a full new server message to
+ handle.)
"""
- if self.message_container[0] == 'BYE':
- raise urwid.ExitMainLoop()
- return
- self.widget.set_text('SERVER: ' + self.message_container[0])
-
-
-class SocketInputWidget(urwid.Filler):
-
- def __init__(self, socket, *args, **kwargs):
- super().__init__(*args, **kwargs)
self.socket = socket
+ self.main_loop = urwid.MainLoop(self.setup_widgets())
+ self.server_output = ['']
+ input_handler = getattr(self.InputHandler(self.reply_widget,
+ self.map_widget,
+ self.server_output),
+ 'handle_input')
+ self.urwid_pipe_write_fd = self.main_loop.watch_pipe(input_handler)
+ self.recv_loop_thread = threading.Thread(target=self.recv_loop)
+
+ def setup_widgets(self):
+ """Return container widget with all widgets we want on our screen.
+
+ Sets up an urwid.Pile inside a returned urwid.Filler; top to bottom:
+ - an EditToSocket widget, prefixing self.socket input with 'SEND: '
+ - self.reply_widget, a urwid.Text widget printing self.socket replies
+ - a 50-col wide urwid.Padding container for self.map_widget, which is
+ to print clipped map representations
+ """
+ edit_widget = self.EditToSocket(self.socket, 'SEND: ')
+ self.reply_widget = urwid.Text('')
+ self.map_widget = urwid.Text('', wrap='clip')
+ map_box = urwid.Padding(self.map_widget, width=50)
+ widget_pile = urwid.Pile([edit_widget, self.reply_widget, map_box])
+ return urwid.Filler(widget_pile)
+
+ class EditToSocket(urwid.Edit):
+ """Extends urwid.Edit with socket to send input on 'enter' to."""
+
+ def __init__(self, socket, *args, **kwargs):
+ super().__init__(*args, **kwargs)
+ self.socket = socket
+
+ def keypress(self, size, key):
+ """Extend super(): on Enter, send .edit_text, and empty it."""
+ if key != 'enter':
+ return super().keypress(size, key)
+ plom_socket_io.send(self.socket, self.edit_text)
+ self.edit_text = ''
+
+ class InputHandler:
+ """Delivers data from other thread to widget via message_container.
+
+ The class only exists to provide handle_input as a bound method, with
+ widget and message_container pre-set, as (bound) handle_input is used
+ as a callback in urwid's watch_pipe – which merely provides its
+ callback target with one parameter for a pipe to read data from an
+ urwid-external thread.
+ """
- def keypress(self, size, key):
- """Act like super(), except on Enter: send .edit_text, and empty it."""
- if key != 'enter':
- return super().keypress(size, key)
- plom_socket_io.send(self.socket, edit.edit_text)
- edit.edit_text = ''
-
-
-s = socket.create_connection(('127.0.0.1', 5000))
-
-edit = urwid.Edit('SEND: ')
-txt = urwid.Text('')
-pile = urwid.Pile([edit, txt])
-fill = SocketInputWidget(s, pile)
-loop = urwid.MainLoop(fill)
+ def __init__(self, widget1, widget2, message_container):
+ self.widget1 = widget1
+ self.widget2 = widget2
+ self.message_container = message_container
+
+ def handle_input(self, trigger):
+ """On input from other thread, either quit or write to widget text.
+
+ Serves as a receiver to urwid's watch_pipe mechanism, with trigger
+ the data that a pipe defined by watch_pipe delivers. To avoid
+ buffering trouble, we don't care for that data beyond the fact that
+ its receival triggers this function: The sender is to write the
+ data it wants to deliver into the container referenced by
+ self.message_container, and just pipe the trigger to inform us
+ about this.
+
+ If the message delivered is 'BYE', quits Urbit.
+ """
+ if self.message_container[0] == 'BYE':
+ raise urwid.ExitMainLoop()
+ return
+ self.widget1.set_text('SERVER: ' + self.message_container[0])
+ self.widget2.set_text('loremipsumdolorsitamet '
+ 'loremipsumdolorsitamet'
+ 'loremipsumdolorsitamet '
+ 'loremipsumdolorsitamet\n'
+ 'loremipsumdolorsitamet '
+ 'loremipsumdolorsitamet')
+
+ def recv_loop(self):
+ """Loop to receive messages from socket and deliver them to urwid.
+
+ Writes finished messages from the socket to self.server_output[0],
+ then sends a single b' ' through self.urwid_pipe_write_fd to trigger
+ the urwid code to read from it.
+ """
+ import os
+ for msg in plom_socket_io.recv(self.socket):
+ self.server_output[0] = msg
+ os.write(self.urwid_pipe_write_fd, b' ')
-server_output = ['']
-write_fd = loop.watch_pipe(getattr(InputHandler(txt, server_output),
- 'handle_input'))
-thread = threading.Thread(target=recv_loop,
- kwargs={'socket': s, 'server_output': server_output,
- 'urwid_pipe_write_fd': write_fd})
-thread.start()
+ def run(self):
+ """Run in parallel main and recv_loop thread."""
+ self.recv_loop_thread.start()
+ self.main_loop.run()
+ self.recv_loop_thread.join()
-loop.run()
-thread.join()
+s = socket.create_connection(('127.0.0.1', 5000))
+u = UrwidSetup(s)
+u.run()
s.close()
projects / plomrogue2-experiments / commitdiff