import socketserver
import threading
import queue
+from parser import ArgError, Parser
+
# Avoid "Address already in use" errors.
socketserver.TCPServer.allow_reuse_address = True
+class GameError(Exception):
+ pass
+
+
class Server(socketserver.ThreadingTCPServer):
"""Bind together threaded IO handling server and message queue."""
self.request.close()
+class Task:
+
+ def __init__(self, name, args=(), kwargs={}):
+ self.name = name
+ self.args = args
+ self.kwargs = kwargs
+ self.todo = 1
+
+
class Thing:
- def __init__(self, position):
+ def __init__(self, world, type_, position):
+ self.world = world
+ self.type_ = type_
self.position = position
- self.task = 'wait'
- self.todo = 0
+ self.task = Task('wait')
+
+ def _move_pos(self, direction, pos_yx):
+ if direction == 'UP':
+ pos_yx[0] -= 1
+ elif direction == 'DOWN':
+ pos_yx[0] += 1
+ elif direction == 'RIGHT':
+ pos_yx[1] += 1
+ elif direction == 'LEFT':
+ pos_yx[1] -= 1
def task_wait(self):
pass
- def task_moveup(self):
- self.position[0] -= 1
-
- def task_movedown(self):
- self.position[0] += 1
+ def task_move(self, direction):
+ self._move_pos(direction, self.position)
def decide_task(self):
- self.set_task('wait')
+ if self.position[1] > 1:
+ self.set_task('move', 'LEFT')
+ elif self.position[1] < 3:
+ self.set_task('move', 'RIGHT')
+ else:
+ self.set_task('wait')
- def set_task(self, task):
- self.task = task
- self.todo = 1
+ def check_task(self, task, *args, **kwargs):
+ if task == 'move':
+ if len(args) > 0:
+ direction = args[0]
+ else:
+ direction = kwargs['direction']
+ test_pos = self.position[:]
+ self._move_pos(direction, test_pos)
+ if test_pos[0] < 0 or test_pos[1] < 0 or \
+ test_pos[0] >= self.world.map_size[0] or \
+ test_pos[1] >= self.world.map_size[1]:
+ raise GameError('would move outside map bounds')
+ pos_i = test_pos[0] * self.world.map_size[1] + test_pos[1]
+ map_tile = self.world.map_[pos_i]
+ if map_tile != '.':
+ raise GameError('would move into illegal terrain')
+
+ def set_task(self, task, *args, **kwargs):
+ self.check_task(task, *args, **kwargs)
+ self.task = Task(task, args, kwargs)
def proceed(self, is_AI=True):
"""Further the thing in its tasks.
- Decrements self.todo; if it thus falls to <= 0, enacts the method whose
- name is 'task_' + self.task and sets self.task = None. If is_AI, calls
- self.decide_task to decide a new self.task.
+ Decrements .task.todo; if it thus falls to <= 0, enacts method whose
+ name is 'task_' + self.task.name and sets .task = None. If is_AI, calls
+ .decide_task to decide a self.task.
"""
- self.todo -= 1
- if self.todo <= 0:
- task= getattr(self, 'task_' + self.task)
- task()
+ self.task.todo -= 1
+ if self.task.todo <= 0:
+ task = getattr(self, 'task_' + self.task.name)
+ task(*self.task.args, **self.task.kwargs)
self.task = None
if is_AI and self.task is None:
self.decide_task()
def __init__(self):
self.turn = 0
self.map_size = (5, 5)
- self.map_ = 'xxxxx\n'+\
- 'x...x\n'+\
- 'x.X.x\n'+\
- 'x...x\n'+\
+ self.map_ = 'xxxxx' +\
+ 'x...x' +\
+ 'x.X.x' +\
+ 'x...x' +\
'xxxxx'
- self.things = [Thing(position=[3, 3]), Thing([1, 1])]
+ self.things = [
+ Thing(self, 'human', [3, 3]),
+ Thing(self, 'monster', [1, 1])
+ ]
self.player_i = 0
self.player = self.things[self.player_i]
return fib(n-1) + fib(n-2)
-class ArgumentError(Exception):
- pass
-
-
class CommandHandler:
def __init__(self, queues_out):
from multiprocessing import Pool
self.queues_out = queues_out
self.world = World()
+ self.parser = Parser(self)
# self.pool and self.pool_result are currently only needed by the FIB
# command and the demo of a parallelized game loop in cmd_inc_p.
self.pool = Pool()
self.pool_result = None
+ def handle_input(self, input_, connection_id):
+ """Process input_ to command grammar, call command handler if found."""
+ try:
+ command = self.parser.parse(input_)
+ if command is None:
+ self.send_to(connection_id, 'UNHANDLED INPUT')
+ else:
+ command(connection_id=connection_id)
+ except ArgError as e:
+ self.send_to(connection_id, 'ARGUMENT ERROR: ' + str(e))
+ except GameError as e:
+ self.send_to(connection_id, 'GAME ERROR: ' + str(e))
+
def send_to(self, connection_id, msg):
"""Send msg to client of connection_id."""
self.queues_out[connection_id].put(msg)
"""Transform tuple (y,x) into string 'Y:'+str(y)+',X:'+str(x)."""
return 'Y:' + str(tuple_[0]) + ',X:' + str(tuple_[1])
+ def quoted(self, string):
+ """Quote and escape string so client interprets it as single token."""
+ quoted = []
+ quoted += ['"']
+ for c in string:
+ if c in {'"', '\\'}:
+ quoted += ['\\']
+ quoted += [c]
+ quoted += ['"']
+ return ''.join(quoted)
+
+ def quoted_map(self, map_string, map_width):
+ """Put \n into map_string at map_width intervals, return quoted whole."""
+ map_lines = []
+ map_size = len(map_string)
+ start_cut = 0
+ while start_cut < map_size:
+ limit = start_cut + map_width
+ map_lines += [map_string[start_cut:limit]]
+ start_cut = limit
+ return self.quoted("\n".join(map_lines))
+
+ def send_all_gamestate(self):
+ """Send out game state data relevant to clients."""
+ self.send_all('NEW_TURN ' + str(self.world.turn))
+ self.send_all('MAP_SIZE ' + self.stringify_yx(self.world.map_size))
+ self.send_all('TERRAIN\n' + self.quoted_map(self.world.map_,
+ self.world.map_size[1]))
+ for thing in self.world.things:
+ self.send_all('THING TYPE:' + thing.type_ + ' '
+ + self.stringify_yx(thing.position))
+
def proceed_to_next_player_turn(self, connection_id):
"""Run game world turns until player can decide their next step.
for thing in self.world.things[self.world.player_i+1:]:
thing.proceed()
self.world.turn += 1
- for thing in self.world.things[:self.world.player_i]:
+ for thing in self.world.things[:self.world.player_i]:
thing.proceed()
self.world.player.proceed(is_AI=False)
if self.world.player.task is None:
break
- self.send_all('NEW_TURN ' + str(self.world.turn))
- self.send_all('MAP_SIZE ' + self.stringify_yx(self.world.map_size))
- self.send_all('TERRAIN\n' + self.world.map_)
- self.send_all('POSITION ' + self.stringify_yx(self.world.player.position))
+ self.send_all_gamestate()
+
+ def cmd_MOVE(self, direction, connection_id):
+ """Set player task to 'move' with direction arg, finish player turn."""
+ if direction not in {'UP', 'DOWN', 'RIGHT', 'LEFT'}:
+ raise ArgError('Move argument must be one of: '
+ 'UP, DOWN, RIGHT, LEFT')
+ self.world.player.set_task('move', direction=direction)
+ self.proceed_to_next_player_turn(connection_id)
+ cmd_MOVE.argtypes = 'string'
+
+ def cmd_WAIT(self, connection_id):
+ """Set player task to 'wait', finish player turn."""
+ self.world.player.set_task('wait')
+ self.proceed_to_next_player_turn(connection_id)
+
+ def cmd_GET_TURN(self, connection_id):
+ """Send world.turn to caller."""
+ self.send_to(connection_id, str(self.world.turn))
+
+ def cmd_ECHO(self, msg, connection_id):
+ """Send msg to caller."""
+ self.send_to(connection_id, msg)
+ cmd_ECHO.argtypes = 'string'
+
+ def cmd_ALL(self, msg, connection_id):
+ """Send msg to all clients."""
+ self.send_all(msg)
+ cmd_ALL.argtypes = 'string'
- def cmd_fib(self, tokens, connection_id):
+ def cmd_FIB(self, numbers, connection_id):
"""Reply with n-th Fibonacci numbers, n taken from tokens[1:].
Numbers are calculated in parallel as far as possible, using fib().
A 'CALCULATING …' message is sent to caller before the result.
"""
- if len(tokens) < 2:
- raise ArgumentError('FIB NEEDS AT LEAST ONE ARGUMENT')
- numbers = []
- for token in tokens[1:]:
- if token == '0' or not token.isdigit():
- raise ArgumentError('FIB ARGUMENTS MUST BE INTEGERS > 0')
- numbers += [int(token)]
self.send_to(connection_id, 'CALCULATING …')
results = self.pool.map(fib, numbers)
reply = ' '.join([str(r) for r in results])
self.send_to(connection_id, reply)
+ cmd_FIB.argtypes = 'seq:int:nonneg'
- def cmd_inc_p(self, connection_id):
+ def cmd_INC_P(self, connection_id):
"""Increment world.turn, send game turn data to everyone.
To simulate game processing waiting times, a one second delay between
self.send_all('TURN_FINISHED ' + str(self.world.turn))
sleep(1)
self.world.turn += 1
- self.send_all('NEW_TURN ' + str(self.world.turn))
- self.send_all('MAP_SIZE ' + self.stringify_yx(self.world.map_size))
- self.send_all('TERRAIN\n' + self.world.map_)
- self.send_all('POSITION ' + self.stringify_yx(self.world.player.position))
+ self.send_all_gamestate()
self.pool_result = self.pool.map_async(fib, (35, 35))
- def cmd_get_turn(self, connection_id):
- """Send world.turn to caller."""
- self.send_to(connection_id, str(self.world.turn))
-
- def cmd_move(self, direction, connection_id):
- """Set player task to 'moveup' or 'movedown', finish player turn."""
- if not direction in {'UP', 'DOWN'}:
- raise ArgumentError('MOVE ARGUMENT MUST BE "UP" or "DOWN"')
- if direction == 'UP':
- self.world.player.set_task('moveup')
- else:
- self.world.player.set_task('movedown')
- self.proceed_to_next_player_turn(connection_id)
-
- def cmd_wait(self, connection_id):
- """Set player task to 'wait', finish player turn."""
- self.world.player.set_task('wait')
- self.proceed_to_next_player_turn(connection_id)
-
- def cmd_echo(self, tokens, input_, connection_id):
- """Send message in input_ beyond tokens[0] to caller."""
- msg = input_[len(tokens[0]) + 1:]
- self.send_to(connection_id, msg)
-
- def cmd_all(self, tokens, input_):
- """Send message in input_ beyond tokens[0] to all clients."""
- msg = input_[len(tokens[0]) + 1:]
- self.send_all(msg)
-
- def handle_input(self, input_, connection_id):
- """Process input_ to command grammar, call command handler if found."""
- tokens = [token for token in input_.split(' ') if len(token) > 0]
- try:
- if len(tokens) == 0:
- self.send_to(connection_id, 'EMPTY COMMAND')
- elif len(tokens) == 1 and tokens[0] == 'INC_P':
- self.cmd_inc_p(connection_id)
- elif len(tokens) == 1 and tokens[0] == 'GET_TURN':
- self.cmd_get_turn(connection_id)
- elif len(tokens) == 1 and tokens[0] == 'WAIT':
- self.cmd_wait(connection_id)
- elif len(tokens) == 2 and tokens[0] == 'MOVE':
- self.cmd_move(tokens[1], connection_id)
- elif len(tokens) >= 1 and tokens[0] == 'ECHO':
- self.cmd_echo(tokens, input_, connection_id)
- elif len(tokens) >= 1 and tokens[0] == 'ALL':
- self.cmd_all(tokens, input_)
- elif len(tokens) >= 1 and tokens[0] == 'FIB':
- # TODO: Should this really block the whole loop?
- self.cmd_fib(tokens, connection_id)
- else:
- self.send_to(connection_id, 'UNKNOWN COMMAND')
- except ArgumentError as e:
- self.send_to(connection_id, 'ARGUMENT ERROR: ' + str(e))
-
def io_loop(q):
"""Handle commands coming through queue q, send results back.