8 from parser import ArgError, Parser
9 from server_.game import World, GameError
12 # Avoid "Address already in use" errors.
13 socketserver.TCPServer.allow_reuse_address = True
16 class Server(socketserver.ThreadingTCPServer):
17 """Bind together threaded IO handling server and message queue."""
19 def __init__(self, queue, *args, **kwargs):
20 super().__init__(*args, **kwargs)
21 self.queue_out = queue
22 self.daemon_threads = True # Else, server's threads have daemon=False.
25 class IO_Handler(socketserver.BaseRequestHandler):
28 """Move messages between network socket and main thread via queues.
30 On start, sets up new queue, sends it via self.server.queue_out to
31 main thread, and from then on receives messages to send back from the
32 main thread via that new queue.
34 At the same time, loops over socket's recv to get messages from the
35 outside via self.server.queue_out into the main thread. Ends connection
36 once a 'QUIT' message is received from socket, and then also kills its
39 All messages to the main thread are tuples, with the first element a
40 meta command ('ADD_QUEUE' for queue creation, 'KILL_QUEUE' for queue
41 deletion, and 'COMMAND' for everything else), the second element a UUID
42 that uniquely identifies the thread (so that the main thread knows whom
43 to send replies back to), and optionally a third element for further
48 def caught_send(socket, message):
49 """Send message by socket, catch broken socket connection error."""
51 plom_socket_io.send(socket, message)
52 except plom_socket_io.BrokenSocketConnection:
55 def send_queue_messages(socket, queue_in, thread_alive):
56 """Send messages via socket from queue_in while thread_alive[0]."""
57 while thread_alive[0]:
59 msg = queue_in.get(timeout=1)
62 caught_send(socket, msg)
65 print('CONNECTION FROM:', str(self.client_address))
66 connection_id = uuid.uuid4()
67 queue_in = queue.Queue()
68 self.server.queue_out.put(('ADD_QUEUE', connection_id, queue_in))
70 t = threading.Thread(target=send_queue_messages,
71 args=(self.request, queue_in, thread_alive))
73 for message in plom_socket_io.recv(self.request):
75 caught_send(self.request, 'BAD MESSAGE')
76 elif 'QUIT' == message:
77 caught_send(self.request, 'BYE')
80 self.server.queue_out.put(('COMMAND', connection_id, message))
81 self.server.queue_out.put(('KILL_QUEUE', connection_id))
82 thread_alive[0] = False
83 print('CONNECTION CLOSED FROM:', str(self.client_address))
88 """Calculate n-th Fibonacci number. Very inefficiently."""
92 return fib(n-1) + fib(n-2)
98 from multiprocessing import Pool
101 self.parser = Parser(self)
102 # self.pool and self.pool_result are currently only needed by the FIB
103 # command and the demo of a parallelized game loop in cmd_inc_p.
105 self.pool_result = None
107 def handle_input(self, input_, connection_id=None, abort_on_error=False):
108 """Process input_ to command grammar, call command handler if found."""
110 command = self.parser.parse(input_)
112 self.send_to(connection_id, 'UNHANDLED INPUT')
114 command(connection_id=connection_id)
115 except ArgError as e:
116 self.send_to(connection_id, 'ARGUMENT ERROR: ' + str(e))
119 except GameError as e:
120 self.send_to(connection_id, 'GAME ERROR: ' + str(e))
124 def send_to(self, connection_id, msg):
125 """Send msg to client of connection_id; if no later, print instead."""
127 self.queues_out[connection_id].put(msg)
131 def send_all(self, msg):
132 """Send msg to all clients."""
133 for connection_id in self.queues_out:
134 self.send_to(connection_id, msg)
136 def stringify_yx(self, tuple_):
137 """Transform tuple (y,x) into string 'Y:'+str(y)+',X:'+str(x)."""
138 return 'Y:' + str(tuple_[0]) + ',X:' + str(tuple_[1])
140 def quoted(self, string):
141 """Quote and escape string so client interprets it as single token."""
149 return ''.join(quoted)
151 def send_all_gamestate(self):
152 """Send out game state data relevant to clients."""
153 self.send_all('NEW_TURN ' + str(self.world.turn))
154 self.send_all('MAP_SIZE ' + self.stringify_yx(self.world.map_size))
155 for y in range(self.world.map_size[0]):
156 width = self.world.map_size[1]
157 terrain_line = self.world.terrain_map[y * width:(y + 1) * width]
158 self.send_all('TERRAIN_LINE %5s %s' % (y, self.quoted(terrain_line)))
159 for thing in self.world.things:
160 self.send_all('THING_TYPE %s %s' % (thing.id_, thing.type_))
161 self.send_all('THING_POS %s %s' % (thing.id_, self.stringify_yx(thing.position)))
164 """Send turn finish signal, run game world, send new world data.
166 First sends 'TURN_FINISHED' message, then runs game world
167 until new player input is needed, then sends game state.
169 self.send_all('TURN_FINISHED ' + str(self.world.turn))
170 self.world.proceed_to_next_player_turn()
171 self.send_all_gamestate()
173 def get_player(self):
174 return self.world.get_thing(self.world.player_id)
176 def cmd_MOVE(self, direction, connection_id):
177 """Set player task to 'move' with direction arg, finish player turn."""
178 if direction not in {'UP', 'DOWN', 'RIGHT', 'LEFT'}:
179 raise ArgError('Move argument must be one of: '
180 'UP, DOWN, RIGHT, LEFT')
181 self.get_player().set_task('move', direction=direction)
183 cmd_MOVE.argtypes = 'string'
185 def cmd_WAIT(self, connection_id):
186 """Set player task to 'wait', finish player turn."""
187 self.get_player().set_task('wait')
190 def cmd_MAP_SIZE(self, yx, connection_id):
191 self.world.set_map_size(yx)
192 cmd_MAP_SIZE.argtypes = 'yx_tuple:nonneg'
194 def cmd_TERRAIN_LINE(self, y, line, connection_id):
195 self.world.set_map_line(y, line)
196 cmd_TERRAIN_LINE.argtypes = 'int:nonneg string'
198 def cmd_THING_TYPE(self, i, type_, connection_id):
199 t = self.world.get_thing(i)
201 cmd_THING_TYPE.argtypes = 'int:nonneg string'
203 def cmd_THING_POS(self, i, yx, connection_id):
204 t = self.world.get_thing(i)
205 t.position = list(yx)
206 cmd_THING_POS.argtypes = 'int:nonneg yx_tuple:nonneg'
208 def cmd_GET_TURN(self, connection_id):
209 """Send world.turn to caller."""
210 self.send_to(connection_id, str(self.world.turn))
212 def cmd_ECHO(self, msg, connection_id):
213 """Send msg to caller."""
214 self.send_to(connection_id, msg)
215 cmd_ECHO.argtypes = 'string'
217 def cmd_ALL(self, msg, connection_id):
218 """Send msg to all clients."""
220 cmd_ALL.argtypes = 'string'
222 def cmd_FIB(self, numbers, connection_id):
223 """Reply with n-th Fibonacci numbers, n taken from tokens[1:].
225 Numbers are calculated in parallel as far as possible, using fib().
226 A 'CALCULATING …' message is sent to caller before the result.
228 self.send_to(connection_id, 'CALCULATING …')
229 results = self.pool.map(fib, numbers)
230 reply = ' '.join([str(r) for r in results])
231 self.send_to(connection_id, reply)
232 cmd_FIB.argtypes = 'seq:int:nonneg'
234 def cmd_INC_P(self, connection_id):
235 """Increment world.turn, send game turn data to everyone.
237 To simulate game processing waiting times, a one second delay between
238 TURN_FINISHED and NEW_TURN occurs; after NEW_TURN, some expensive
239 calculations are started as pool processes that need to be finished
240 until a further INC finishes the turn.
242 This is just a demo structure for how the game loop could work when
243 parallelized. One might imagine a two-step game turn, with a non-action
244 step determining actor tasks (the AI determinations would take the
245 place of the fib calculations here), and an action step wherein these
246 tasks are performed (where now sleep(1) is).
248 from time import sleep
249 if self.pool_result is not None:
250 self.pool_result.wait()
251 self.send_all('TURN_FINISHED ' + str(self.world.turn))
254 self.send_all_gamestate()
255 self.pool_result = self.pool.map_async(fib, (35, 35))
258 def io_loop(q, commander):
259 """Handle commands coming through queue q, send results back.
261 Commands from q are expected to be tuples, with the first element either
262 'ADD_QUEUE', 'COMMAND', or 'KILL_QUEUE', the second element a UUID, and
263 an optional third element of arbitrary type. The UUID identifies a
264 receiver for replies.
266 An 'ADD_QUEUE' command should contain as third element a queue through
267 which to send messages back to the sender of the command. A 'KILL_QUEUE'
268 command removes the queue for that receiver from the list of queues through
269 which to send replies.
271 A 'COMMAND' command is specified in greater detail by a string that is the
272 tuple's third element. The commander CommandHandler takes care of processing
273 this and sending out replies.
279 content = None if len(x) == 2 else x[2]
280 if command_type == 'ADD_QUEUE':
281 commander.queues_out[connection_id] = content
282 elif command_type == 'COMMAND':
283 commander.handle_input(content, connection_id)
284 elif command_type == 'KILL_QUEUE':
285 del commander.queues_out[connection_id]
288 if len(sys.argv) != 2:
289 print('wrong number of arguments, expected one (game file)')
291 game_file_name = sys.argv[1]
292 commander = CommandHandler()
293 if os.path.exists(game_file_name):
294 if not os.path.isfile(game_file_name):
295 print('game file name does not refer to a valid game file')
297 with open(game_file_name, 'r') as f:
298 lines = f.readlines()
299 for i in range(len(lines)):
301 print("FILE INPUT LINE %s: %s" % (i, line), end='')
302 commander.handle_input(line, abort_on_error=True)
304 commander.handle_input('MAP_SIZE Y:5,X:5')
305 commander.handle_input('TERRAIN_LINE 0 "xxxxx"')
306 commander.handle_input('TERRAIN_LINE 1 "x...x"')
307 commander.handle_input('TERRAIN_LINE 2 "x.X.x"')
308 commander.handle_input('TERRAIN_LINE 3 "x...x"')
309 commander.handle_input('TERRAIN_LINE 4 "xxxxx"')
310 commander.handle_input('THING_TYPE 0 human')
311 commander.handle_input('THING_POS 0 Y:3,X:3')
312 commander.handle_input('THING_TYPE 1 monster')
313 commander.handle_input('THING_POS 1 Y:1,X:1')
315 c = threading.Thread(target=io_loop, daemon=True, args=(q, commander))
317 server = Server(q, ('localhost', 5000), IO_Handler)
319 server.serve_forever()
320 except KeyboardInterrupt:
323 print('Killing server')
324 server.server_close()