syncplay/syncplay/server.py
2012-02-15 19:45:05 +01:00

330 lines
10 KiB
Python

#coding:utf8
import time
import random
from twisted.internet import reactor
from twisted.internet.protocol import Factory
from .network_utils import (
arg_count,
CommandProtocol,
)
from .utils import parse_state
random.seed()
CHARS = 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789'
def random_chars():
return ''.join(random.choice(CHARS) for _ in xrange(10))
class SyncServerProtocol(CommandProtocol):
def __init__(self, factory):
CommandProtocol.__init__(self)
self.factory = factory
def connectionLost(self, reason):
self.factory.remove_watcher(self)
def handle_init_iam(self, args):
if not len(args) == 1:
self.drop_with_error('Invalid arguments')
return
self.factory.add_watcher(self, args[0])
self.change_state('connected')
@arg_count(3)
def handle_connected_state(self, args):
args = parse_state(args)
if not args:
self.drop_with_error('Malformed state attributes')
return
counter, paused, position, _ = args
self.factory.update_state(self, counter, paused, position)
@arg_count(2)
def handle_connected_seek(self, args):
try:
counter = int(args[0])
position = int(args[1])
except ValueError:
self.drop_with_error('Invalid arguments')
position /= 1000.0
self.factory.seek(self, counter, position)
@arg_count(2)
def handle_connected_pong(self, args):
value, ctime = args
try:
ctime = int(ctime)
except ValueError:
self.drop_with_error('Invalid arguments')
ctime /= 100000.0
self.factory.pong_received(self, value, ctime)
@arg_count(1)
def handle_connected_playing(self, args):
self.factory.playing_received(self, args[0])
def __hash__(self):
return hash('|'.join((
self.transport.getPeer().host,
str(id(self)),
)))
def send_state(self, counter, paused, position, who_last_changed):
paused = 'paused' if paused else 'playing'
position = int(position*1000)
if who_last_changed is None:
self.send_message('state', counter, paused, position)
else:
self.send_message('state', counter, paused, position, who_last_changed)
def send_seek(self, position, who_seeked):
self.send_message('seek', int(position*1000), who_seeked)
def send_ping(self, value):
self.send_message('ping', value)
def send_playing(self, who, what):
self.send_message('playing', who, what)
def send_present(self, who, what):
if what:
self.send_message('present', who, what)
else:
self.send_message('present', who)
def send_joined(self, who):
self.send_message('joined', who)
def send_left(self, who):
self.send_message('left', who)
def send_hello(self):
self.send_message('hello')
states = dict(
init = dict(
iam = 'handle_init_iam',
),
connected = dict(
state = 'handle_connected_state',
seek = 'handle_connected_seek',
pong = 'handle_connected_pong',
playing = 'handle_connected_playing',
),
)
initial_state = 'init'
class WatcherInfo(object):
def __init__(self, watcher_proto, name):
self.watcher_proto = watcher_proto
self.name = name
self.position = 0
self.filename = None
self.max_position = 0
self.last_update = None
self.last_update_sent = None
self.ping = None
self.time_offset = 0
self.time_offset_data = []
self.last_ping_time = None
self.last_ping_value = None
self.counter = 0
class SyncFactory(Factory):
def __init__(self, min_pause_lock = 3, update_time_limit = 1):
self.watchers = dict()
self.paused = True
self.pause_change_time = None
self.pause_change_by = None
self.min_pause_lock = min_pause_lock
self.update_time_limit = update_time_limit
def buildProtocol(self, addr):
return SyncServerProtocol(self)
def add_watcher(self, watcher_proto, name):
watcher = WatcherInfo(watcher_proto, name)
if self.watchers:
watcher.max_position = min(w.max_position for w in self.watchers.itervalues())
self.watchers[watcher_proto] = watcher
for receiver in self.watchers.itervalues():
if receiver == watcher:
continue
receiver.watcher_proto.send_joined(name)
watcher_proto.send_present(receiver.name, receiver.filename)
watcher_proto.send_hello()
self.send_state_to(watcher)
self.schedule_send_ping(watcher_proto)
def remove_watcher(self, watcher_proto):
watcher = self.watchers.pop(watcher_proto, None)
for receiver in self.watchers.itervalues():
if receiver != watcher:
receiver.watcher_proto.send_left(watcher.name)
if self.pause_change_by == watcher:
self.pause_change_time = None
self.pause_change_by = None
if not self.watchers:
self.paused = True
# send info someone quit
def update_state(self, watcher_proto, counter, paused, position):
watcher = self.watchers.get(watcher_proto)
if not watcher:
return
if not paused and watcher.ping is not None:
position += watcher.ping
watcher.position = position
watcher.max_position = max(position, watcher.max_position)
watcher.last_update = time.time()
watcher.counter = counter
pause_changed = paused != self.paused
curtime = time.time()
if pause_changed and (
not self.pause_change_by or
self.pause_change_by == watcher or
(curtime-self.pause_change_time) > self.min_pause_lock
):
self.paused = not self.paused
self.pause_change_time = curtime
self.pause_change_by = watcher
else:
pause_changed = False
position = self.find_position()
for receiver in self.watchers.itervalues():
if (
receiver == watcher or
pause_changed or
(curtime-receiver.last_update_sent) > self.update_time_limit
):
self.send_state_to(receiver, position, curtime)
def seek(self, watcher_proto, counter, position):
watcher = self.watchers.get(watcher_proto)
if not watcher:
return
#print watcher.name, 'seeked to', position
if not self.paused and watcher.ping is not None:
position += watcher.ping
watcher.counter = counter
for receiver in self.watchers.itervalues():
position2 = position
if not self.paused and receiver.ping is not None:
position2 += receiver.ping
receiver.max_position = position2
if receiver == watcher:
# send_state_to modifies by ping already...
self.send_state_to(receiver, position)
else:
receiver.watcher_proto.send_seek(position2, watcher.name)
def send_state_to(self, watcher, position=None, curtime=None):
if position is None:
position = self.find_position()
if curtime is None:
curtime = time.time()
if not self.paused and watcher.ping is not None:
position += watcher.ping
if self.pause_change_by:
watcher.watcher_proto.send_state(watcher.counter, self.paused, position, self.pause_change_by.name)
else:
watcher.watcher_proto.send_state(watcher.counter, self.paused, position, None)
watcher.last_update_sent = curtime
def find_position(self):
curtime = time.time()
try:
return min(
max(watcher.max_position, watcher.position + (0 if self.paused else curtime-watcher.last_update))
for watcher in self.watchers.itervalues()
if watcher.last_update
)
except ValueError:
#min() arg is an empty sequence
return 0.0
def pong_received(self, watcher_proto, value, ctime):
watcher = self.watchers.get(watcher_proto)
if not watcher:
return
if watcher.last_ping_value == value:
curtime = time.time()
watcher.ping = ping = (curtime - watcher.last_ping_time)/2
if watcher.time_offset_data is not None:
time_offset = curtime - (ctime + ping)
watcher.time_offset_data.append((ping, time_offset))
if len(watcher.time_offset_data) > 1:
pmax = max(p for p,_ in watcher.time_offset_data)
psum, pweights = 0, 0
for ping, offset in watcher.time_offset_data:
ping = 1-(ping/pmax)
pweights += ping
psum += ping*offset
watcher.time_offset = psum/pweights
else:
watcher.time_offset = time_offset
if len(watcher.time_offset_data) > 20:
watcher.time_offset_data = None
#print watcher.name, 'last ping', watcher.ping, 'time offset %.6f' % watcher.time_offset
self.schedule_send_ping(watcher_proto)
def send_ping_to(self, watcher_proto):
watcher = self.watchers.get(watcher_proto)
if not watcher:
return
chars = random_chars()
watcher.last_ping_time = time.time()
watcher.last_ping_value = chars
watcher.watcher_proto.send_ping(chars)
def schedule_send_ping(self, watcher_proto, when=1):
reactor.callLater(when, self.send_ping_to, watcher_proto)
def playing_received(self, watcher_proto, filename):
watcher = self.watchers.get(watcher_proto)
if not watcher:
return
watcher.filename = filename
for receiver in self.watchers.itervalues():
if receiver != watcher:
receiver.watcher_proto.send_playing(watcher.name, filename)