def __init__(self):
self.db = Database()
self.cache = {}
self.live_set = set() # The live set tracks ThingProxies that are keeping Things loaded
self.cache_task = task.LoopingCall(self.purge_cache)
self.cache_task.start(300)
self.ThingProxy = ThingProxyFactory(self)
class World(object):
"""
The World class represents the game world. It manages the collection of objects that together comprise the world.
"""
def __init__(self):
self.db = Database()
self.cache = {}
self.live_set = set() # The live set tracks ThingProxies that are keeping Things loaded
self.cache_task = task.LoopingCall(self.purge_cache)
self.cache_task.start(300)
self.ThingProxy = ThingProxyFactory(self)
def close(self):
# Immediately purge (and save, if neccessary) all cached objects
self.purge_cache(-1)
self.db.close()
def connect(self, username, password=None):
"""Connects a player to the world."""
if password is not None:
obj = self.db.player_login(username, password)
if obj == -1: return None
else:
obj = self.db.get_player_id(username)
return self.get_thing(obj) if obj else None
def get_thing(self, obj):
"""
Retrieves the Thing with the given database ID.
Actually returns a ThingProxy that facilitates lazy-loading of Things and
allows Things to be unloaded in the background to save memory, and transparently
loaded again upon demand.
"""
if not obj in self.cache:
log(LogLevel.Trace, "Cache: MISS #{0}".format(obj))
return self.ThingProxy(self, obj)
else:
log(LogLevel.Trace, "Cache: Hit #{0}".format(obj))
return self.cache[obj]
def purge_cache(self, expiry=3600): #TODO: Rename this function?
"""
Remove from the cache all cached objects older than the given time.
Save any objects that have been modified since they were cached.
"""
threshold = int(time.time()) - expiry # Threshold is a time in the past
cachesize = len(self.cache)
#self.cache = [x for x in self.cache if x[1] > threshold]
objects = self.live_set.copy()
for obj in objects:
if obj.cachetime < threshold:
obj.unload() # Save and unload the object
elif obj.dirty:
obj.save()
log(LogLevel.Trace, "Cache: Purged {0} stale objects from memory".format(len(objects)-len(self.live_set)))
def get_contents(self, thing):
"""Returns a tuple of Things that the given Thing contains."""
try:
# Get list of IDs
items = self.db.get_contents(thing.id)
# Get Things and return them
return map(lambda x: self.get_thing(x), items)
except AttributeError:
raise TypeError("Expected a Thing as argument")
def save_thing(self, thing):
#TODO: Review this function vs. calling thing.force_save()
# Save Thing basic info
self.db.save_object(thing)
# Save any modified properties of the Thing
for prop in thing._propdirty:
self.db.set_property(thing.id, prop, thing._propcache[prop])
def find_user(self, name):
"""
Find a connected user by the given character name.
"""
#TODO: Return user
pass
def list_players(self):
"""
Return a list of all connected characters as Player objects.
"""
pass
