Improved CLI and client connection.

telematica/ass1/async.py

@@ -2,23 +2,31 @@ import asyncore, socket
 from Queue import Queue
 import re
 
-class ChatClient(asyncore.dispatcher):
+class ClientConnection(object, asyncore.dispatcher):
 
-    def __init__(self, host, port, nickname='Foo'):
+    def __init__(self):
         asyncore.dispatcher.__init__(self)
         self.create_socket(socket.AF_INET, socket.SOCK_STREAM)
-        self.connect((host, port))
 
         self.verified = False
         self.authenticated = False
         self.authentification_sent = False
 
-        self.nickname = nickname
+        self.nickname = 'Anonymous'
 
         self.send_queue = Queue()
         self.send_buffer = ''
 
+    def connect(self, addr):
+        self.host = addr[0]
+        self.port = addr[1]
+        super(ClientConnection, self).connect(addr)
+
     def handle_connect(self):
+        """
+        Called when a connection is established. This method will/should be
+        overwritten by the Command Line Interface or an other implementation.
+        """
         pass
 
     def handle_close(self):
@@ -53,6 +61,13 @@ class ChatClient(asyncore.dispatcher):
         else:
             self.parse_notification(buf)
 
+    def handle_write(self):
+        if not self.send_buffer:
+            self.send_buffer = self.send_queue.get() + '\r\n'
+            print '> %s' % self.send_buffer[:-1]
+        sent = self.send(self.send_buffer)
+        self.send_buffer = self.send_buffer[sent:]
+
     def verify_server(self, buf):
         match = re.match('^CHAT/(\d\.\d)/([^\x00-\x1F/:]+)$', buf)
 
@@ -76,13 +91,7 @@ class ChatClient(asyncore.dispatcher):
     def writable(self):
         return not self.send_queue.empty() or len(self.send_buffer)
 
-    def handle_write(self):
-        if not self.send_buffer:
-            self.send_buffer = self.send_queue.get() + '\r\n'
-            print '> %s' % self.send_buffer[:-1]
-        sent = self.send(self.send_buffer)
-        self.send_buffer = self.send_buffer[sent:]
-
 if __name__ == '__main__':
-    client = ChatClient('ow150.science.uva.nl', 16897)
+    client = ClientConnection()
+    client.connect(('ow150.science.uva.nl', 16897))
     asyncore.loop()

telematica/ass1/chat_window.py

@@ -17,33 +17,7 @@ class ChatWindow:
         # True, if help screen is currently displayed.
         self.displayed_help = False
 
-    def handle_close(self):
-        # If the help screen is currently displayed, hide it.
-        if self.displayed_help:
-            self.displayed_help = False
-            self.window.clear()
-            self.window.refresh()
-        else:
-            # Stop user input handler (which will exit the application).
-            self.main.quit()
-
-    def display_help(self):
-        if self.displayed_help:
-            return
-
-        self.displayed_help = True
-
+    def clear(self):
         self.window.clear()
-        help_text = 'Help screen\n' \
-            + '\n' \
-            + 'All commands listed below should be preceded by a slash:\n' \
-            + '\n' \
-            + '  Command\tDescription\n' \
-            + '  close\t\tClose visible chat window (or this help screen).\n' \
-            + '  help\t\tThis help page.\n' \
-            + '  quit\t\tQuit this chat application (shortcut: ^c).\n' \
-
-        for i, line in enumerate(help_text.split('\n')):
-            self.window.addstr(i, 0, line)
         self.window.refresh()
 

telematica/ass1/cli.py

 import curses
 import sys
 
+from async import ClientConnection
 from chat_window import ChatWindow
 from info_bar import InfoBar
 from command_bar import CommandBar
@@ -50,6 +51,12 @@ class CLI:
         # Initialise color scheme.
         curses.init_pair(1, curses.COLOR_WHITE, curses.COLOR_BLUE)
 
+        # No default connection
+        self.connection = None
+
+        # Initialise command handler
+        self.init_command_handler()
+
         # Window composition.
         self.init_windows()
 
@@ -67,7 +74,7 @@ class CLI:
         self.max_y, self.max_x = self.stdscr.getmaxyx()
         self.stdscr.refresh()
 
-        # Initalise chat window.
+        # Initialise chat window.
         self.chat_window = ChatWindow(self, 0, 0, self.max_y - 2, self.max_x)
 
         # Info bar between chat window and command bar
@@ -88,21 +95,144 @@ class CLI:
             try:
                 c = self.stdscr.getch()
             except KeyboardInterrupt:
-                self.quit()
+                self.execute('quit')
 
             if c != curses.ERR and self.command_bar.handle_input(c):
                 break
 
-    def quit(self):
-        # Reverse the curses-friendly terminal settings.
-        curses.nocbreak();
-        self.stdscr.keypad(0);
-        curses.echo()
+    def init_command_handler(self):
 
-        # Restore the terminal to its original operating mode.
-        curses.endwin()
+        def close(main):
+            # If the help screen is currently displayed, hide it.
+            if main.chat_window.displayed_help:
+                main.chat_window.displayed_help = False
+                main.chat_window.clear()
+            else:
+                # Stop user input handler (which will exit the application).
+                main.execute('quit')
+
+        def connect(main, host, port=16897):
+
+            if getattr(port, '__class__') != '<type \'int\'>':
+                port = int(port)
+
+            if main.connection:
+                main.execute('disconnect')
+
+            main.display_info('Connecting to %s:%d...' % (host, port))
+
+            def handle_connect(conn):
+                """Called when a connection is established."""
+                conn.main.display_info('Connected to %s' % conn.host)
+
+            main.connection = ClientConnection()
+            main.connection.main = main
+            main.connection.handle_connect = handle_connect
+            main.connection.connect((host, port))
+
+        def disconnect(main):
+            """
+            Disconnect from chat server. When there is no active connection,
+            this operating will only set the 'Offline' message in the
+            information bar. Otherwise, the active connection is set to None
+            and the 'Offline' message is set to the info bar.
+            """
+
+            self.connection = None
+            self.display_info('Offline. Type "/connect HOST" to connect' \
+                    + ' to another chat server.')
+
+        def help(main):
+            if main.chat_window.displayed_help:
+                return
+
+            main.chat_window.displayed_help = True
+
+            main.chat_window.clear()
+            help_text = """Help screen
+
+All commands listed below should be preceded by a slash:
+
+  Command     Description
+
+  close       Close visible chat window (or this help screen).
+
+  connect     Connect to a chat server using HOSTNAME and optionally a PORT.
+              If no PORT is specified, the default port 16897 is used.
+
+              Synopsis: /connect HOSTNAME [PORT]
+
+              For example, "/connect ow150" will connect to the provided test
+              server of this assignment (when you're using the UvA network).
+
+  disconnect  Disconnect from the currently connected chat server.
+
+  exec        Execute python code. For example. to list all variables and
+              function of the CLI, type: "/exec print dir(main)".
+
+  help        This help page.
+
+  quit        Quit this chat application (shortcut: ^c).
+"""
+
+            for i, line in enumerate(help_text.split('\n')):
+                main.chat_window.window.addstr(i, 0, line)
+            main.chat_window.window.refresh()
+
+        def quit(main):
+            # Reverse the curses-friendly terminal settings.
+            curses.nocbreak();
+            self.stdscr.keypad(0);
+            curses.echo()
+
+            # Restore the terminal to its original operating mode.
+            curses.endwin()
+
+            sys.exit(0)
+
+        def _exec(main, cmd):
+            # Skip the leading "/exec " of the command
+            exec cmd[6:]
+
+        # List of builtin command
+        self.cmd_list = {
+            'close': close,
+            'connect': connect,
+            'disconnect': disconnect,
+            'exec': _exec,
+            'help': help,
+            'quit': quit
+        }
+
+    def display_info(self, msg):
+        """
+        Display a message on the information bar (info_bar). This will erase the
+        existing message on the info bar.
+        """
 
-        sys.exit(0)
+        self.info_bar.display(msg)
+
+    def execute(self, cmd, args=[], raw_command=''):
+
+        if not raw_command:
+            raw_command = cmd
+
+        # Select command from command list.
+        try:
+            cmd_fn = self.cmd_list[cmd]
+        except KeyError:
+            self.display_info('Unknown command "/%s".' % cmd)
+            return
+
+        # Call command handler.
+        try:
+            if cmd == 'exec':
+                cmd_fn(self, raw_command)
+            else:
+                cmd_fn(self, *args)
+        except Exception, e:
+            self.display_info(str(e))
+            return
 
     def __del__(self):
         import curses

telematica/ass1/command_bar.py

 import curses
 from curses.textpad import Textbox
+import re
 
 class CommandBar:
+    """
+    Command bar is part of the Command Line Interface (CLI) of the chat
+    application. The command bar is responsible for handling the user input.
+    This inclues executing commands and (re)drawing the command line.
+    """
+
     def __init__(self, main, top, left, height, width):
         # Reference to the main window
         self.main = main
@@ -17,18 +24,10 @@ class CommandBar:
         self.textbox = Textbox(self.window)
 
     def handle_input(self, c):
-        #if c == ord('Q'):
-        #    return True
-        #if c == ord('q'):
-        #    return self.handle_quit()
-        #if c == ord('h'):
-        #    self.display_help()
-        #elif c == curses.KEY_HOME:
+        #if c == curses.KEY_HOME:
         #    self.x = self.y = 0
-        #if 32 <= c <= 127:
+        #elif 32 <= c <= 127:
         #    self.append_command(c)
-        #elif c == 10: # Enter key
-        #    return self.execute_command()
         self.append_command(c)
 
     def append_command(self, c):
@@ -42,21 +41,19 @@ class CommandBar:
             command = self.textbox.gather()
             self.window.deleteln()
             self.window.move(0, 0)
-        # Handle the given/typed command.
-        self.handle_command(command)
 
-    def handle_command(self, command):
+        command = command.strip()
+
         if not command:
             return
 
         if command[0] == '/':
-            cmd = command.split(' ', 1)[0][1:]
-            if cmd == 'help':
-                self.main.chat_window.display_help()
-            elif cmd == 'quit':
-                self.main.quit()
-            elif cmd == 'close':
-                self.main.chat_window.handle_close()
+            # Split command line into command identifier and arguments.
+            parts = re.split('\s+', command)
+            cmd = parts[0][1:]
+            args = parts[1:]
+
+            self.main.execute(cmd, args, command)
         else:
             pass
 

telematica/ass1/main.py

 #!/usr/bin/env python
 
 from cli import CLI
+import curses
 
 try:
     cli = CLI()