""" This is the *abstract* django models for many of the database objects in Evennia. A django abstract (obs, not the same as a Python metaclass!) is a model which is not actually created in the database, but which only exists for other models to inherit from, to avoid code duplication. Any model can import and inherit from these classes. Attributes are database objects stored on other objects. The implementing class needs to supply a ForeignKey field attr_object pointing to the kind of object being mapped. Attributes storing iterables actually store special types of iterables named PackedList/PackedDict respectively. These make sure to save changes to them to database - this is criticial in order to allow for obj.db.mylist[2] = data. Also, all dbobjects are saved as dbrefs but are also aggressively cached. TypedObjects are objects 'decorated' with a typeclass - that is, the typeclass (which is a normal Python class implementing some special tricks with its get/set attribute methods, allows for the creation of all sorts of different objects all with the same database object underneath. Usually attributes are used to permanently store things not hard-coded as field on the database object. The admin should usually not have to deal directly with the database object layer. This module also contains the Managers for the respective models; inherit from these to create custom managers. """ import sys #try: # import cPickle as pickle #except ImportError: # import pickle import traceback #from collections import defaultdict from django.db import models from django.conf import settings from django.utils.encoding import smart_str from django.contrib.contenttypes.models import ContentType from django.db.models import Q from django.db.models.signals import m2m_changed from src.utils.idmapper.models import SharedMemoryModel from src.server.caches import get_field_cache, set_field_cache, del_field_cache from src.server.caches import get_attr_cache, del_attr_cache, set_attr_cache from src.server.caches import get_prop_cache, set_prop_cache, flush_attr_cache from src.server.caches import post_attr_update #from src.server.caches import call_ndb_hooks from src.server.models import ServerConfig from src.typeclasses import managers from src.locks.lockhandler import LockHandler from src.utils import logger, utils from src.utils.utils import make_iter, is_iter, to_str from src.utils.dbserialize import to_pickle, from_pickle from src.utils.picklefield import PickledObjectField __all__ = ("Attribute", "TypeNick", "TypedObject") _PERMISSION_HIERARCHY = [p.lower() for p in settings.PERMISSION_HIERARCHY] _CTYPEGET = ContentType.objects.get _GA = object.__getattribute__ _SA = object.__setattr__ _DA = object.__delattr__ #------------------------------------------------------------ # # Attributes # #------------------------------------------------------------ class Attribute(SharedMemoryModel): """ Abstract django model. Attributes are things that are specific to different types of objects. For example, a drink container needs to store its fill level, whereas an exit needs to store its open/closed/locked/unlocked state. These are done via attributes, rather than making different classes for each object type and storing them directly. The added benefit is that we can add/remove attributes on the fly as we like. The Attribute class defines the following properties: key - primary identifier lock_storage - perm strings obj - which object the attribute is defined on date_created - when the attribute was created. value - the data stored in the attribute, in pickled form using wrappers to be able to store/retrieve models. strvalue - string-only data. This data is not pickled and is thus faster to search for in the database. category - optional character string for grouping the Attribute """ # # Attribute Database Model setup # # These database fields are all set using their corresponding properties, # named same as the field, but withtout the db_* prefix. db_key = models.CharField('key', max_length=255, db_index=True) # access through the value property db_value = PickledObjectField('value', null=True) # string-specific storage for quick look-up db_strvalue = models.TextField('strvalue', null=True, blank=True) # optional categorization of attribute db_category = models.CharField('category', max_length=128, db_index=True, blank=True, null=True) # Lock storage db_lock_storage = models.TextField('locks', blank=True) # time stamp db_date_created = models.DateTimeField('date_created', editable=False, auto_now_add=True) # Database manager objects = managers.AttributeManager() # Lock handler self.locks def __init__(self, *args, **kwargs): "Initializes the parent first -important!" SharedMemoryModel.__init__(self, *args, **kwargs) self.locks = LockHandler(self) self.no_cache = True self.cached_value = None class Meta: "Define Django meta options" verbose_name = "Evennia Attribute" # Wrapper properties to easily set database fields. These are # @property decorators that allows to access these fields using # normal python operations (without having to remember to save() # etc). So e.g. a property 'attr' has a get/set/del decorator # defined that allows the user to do self.attr = value, # value = self.attr and del self.attr respectively (where self # is the object in question). # key property (wraps db_key) #@property #def __key_get(self): # "Getter. Allows for value = self.key" # return get_field_cache(self, "key") ##@key.setter #def __key_set(self, value): # "Setter. Allows for self.key = value" # set_field_cache(self, "key", value) ##@key.deleter #def __key_del(self): # "Deleter. Allows for del self.key" # raise Exception("Cannot delete attribute key!") #key = property(__key_get, __key_set, __key_del) ## obj property (wraps db_obj) ##@property #def __obj_get(self): # "Getter. Allows for value = self.obj" # return get_field_cache(self, "obj") ##@obj.setter #def __obj_set(self, value): # "Setter. Allows for self.obj = value" # set_field_cache(self, "obj", value) ##@obj.deleter #def __obj_del(self): # "Deleter. Allows for del self.obj" # self.db_obj = None # self.save() # del_field_cache(self, "obj") #obj = property(__obj_get, __obj_set, __obj_del) ## date_created property (wraps db_date_created) ##@property #def __date_created_get(self): # "Getter. Allows for value = self.date_created" # return get_field_cache(self, "date_created") ##@date_created.setter #def __date_created_set(self, value): # "Setter. Allows for self.date_created = value" # raise Exception("Cannot edit date_created!") ##@date_created.deleter #def __date_created_del(self): # "Deleter. Allows for del self.date_created" # raise Exception("Cannot delete date_created!") #date_created = property(__date_created_get, __date_created_set, __date_created_del) # value property (wraps db_value) #@property def __value_get(self): """ Getter. Allows for value = self.value. Reads from cache if possible. """ if self.no_cache: # re-create data from database and cache it value = from_pickle(self.db_value, db_obj=self) self.cached_value = value self.no_cache = False return self.cached_value #@value.setter def __value_set(self, new_value): """ Setter. Allows for self.value = value. We make sure to cache everything. """ to_store = to_pickle(new_value) self.cached_value = from_pickle(to_store, db_obj=self) self.no_cache = False self.db_value = to_store self.save() try: self._track_db_value_change.update(self.cached_value) except AttributeError: pass #@value.deleter def __value_del(self): "Deleter. Allows for del attr.value. This removes the entire attribute." self.delete() value = property(__value_get, __value_set, __value_del) # lock_storage property (wraps db_lock_storage) #@property #def __lock_storage_get(self): # "Getter. Allows for value = self.lock_storage" # return get_field_cache(self, "lock_storage") ##@lock_storage.setter #def __lock_storage_set(self, value): # """Saves the lock_storage. This is usually not called directly, but through self.lock()""" # self.db_lock_storage = value # self.save() ##@lock_storage.deleter #def __lock_storage_del(self): # "Deleter is disabled. Use the lockhandler.delete (self.lock.delete) instead""" # logger.log_errmsg("Lock_Storage (on %s) cannot be deleted. Use obj.lock.delete() instead." % self) #lock_storage = property(__lock_storage_get, __lock_storage_set, __lock_storage_del) # # # Attribute methods # # def __str__(self): return smart_str("%s(%s)" % (_GA(self, "db_key"), _GA(self, "id"))) def __unicode__(self): return u"%s(%s)" % (_GA(self, "db_key"), _GA(self, "id")) def access(self, accessing_obj, access_type='read', default=False): """ Determines if another object has permission to access. accessing_obj - object trying to access this one access_type - type of access sought default - what to return if no lock of access_type was found """ return self.locks.check(accessing_obj, access_type=access_type, default=default) def at_set(self, new_value): """ Hook method called when the attribute changes value. """ pass # # Handlers making use of the Attribute model # class AttributeHandler(object): """ Handler for adding Attributes to the object. """ _m2m_fieldname = "db_attributes" _attrcreate = "attrcreate" _attredit = "attredit" _attrread = "attrread" def __init__(self, obj): "Initialize handler" self.obj = obj def has(self, key, category=None): """ Checks if the given Attribute (or list of Attributes) exists on the object. If an iterable is given, returns list of booleans. """ ret = [] category_cond = Q(db_category__iexact=category) if category else Q() cachekey = "%s%s" % (category, category) for keystr in make_iter(key): if get_attr_cache(self.obj, keystr): ret.append(True) else: ret.append(True if _GA(self.obj, self._m2m_fieldname).filter(Q(db_key__iexact=keystr) & category_cond) else False) return ret[0] if len(ret)==1 else ret def get(self, key, category=None, default=None, return_obj=False, strattr=False, raise_exception=False, accessing_obj=None, default_access=True): """ Returns the value of the given Attribute or list of Attributes. strattr will cause the string-only value field instead of the normal pickled field data. Use to get back values from Attributes added with the strattr keyword. If return_obj=True, return the matching Attribute object instead. Returns None if no matches (or [ ] if key was a list with no matches). If raise_exception=True, failure to find a match will raise AttributeError instead. If accessing_obj is given, its "attrread" permission lock will be checked before displaying each looked-after Attribute. If no accessing_obj is given, no check will be done. """ ret = [] category_cond = Q(db_category__iexact=category) if category else Q() for keystr in make_iter(key): cachekey = "%s%s" % (category if category else "", keystr) attr_obj = get_attr_cache(self.obj, cachekey) if not attr_obj: attr_obj = _GA(self.obj, "db_attributes").filter(Q(db_key__iexact=keystr) & category_cond) if not attr_obj: if raise_exception: raise AttributeError ret.append(default) continue attr_obj = attr_obj[0] # query is evaluated here set_attr_cache(self.obj, cachekey, attr_obj) ret.append(attr_obj) if accessing_obj: # check 'attrread' locks ret = [attr for attr in ret if attr.access(accessing_obj, self._attrread, default=default_access)] if strattr: ret = ret if return_obj else [attr.strvalue if attr else None for attr in ret] else: ret = ret if return_obj else [attr.value if attr else None for attr in ret] return ret[0] if len(ret)==1 else ret def add(self, key, value, category=None, lockstring="", strattr=False, accessing_obj=None, default_access=True): """ Add attribute to object, with optional lockstring. If strattr is set, the db_strvalue field will be used (no pickling). Use the get() method with the strattr keyword to get it back. If accessing_obj is given, self.obj's 'attrcreate' lock access will be checked against it. If no accessing_obj is given, no check will be done. """ if accessing_obj and not self.obj.access(accessing_obj, self._attrcreate, default=default_access): # check create access return cachekey = "%s%s" % (category if category else "", key) attr_obj = get_attr_cache(self.obj, cachekey) if not attr_obj: # check if attribute already exists attr_obj = _GA(self.obj, self._m2m_fieldname).filter(db_key__iexact=key) if attr_obj.count(): # re-use old attribute object attr_obj = attr_obj[0] set_attr_cache(self.obj, key, attr_obj) # renew cache else: # no old attr available; create new (caches automatically) attr_obj = Attribute(db_key=key, db_category=category) attr_obj.save() # important _GA(self.obj, self._m2m_fieldname).add(attr_obj) if lockstring: attr_obj.locks.add(lockstring) # we shouldn't need to fear stale objects, the field signalling should catch all cases if strattr: # store as a simple string attr_obj.strvalue = value else: # pickle arbitrary data attr_obj.value = value def remove(self, key, raise_exception=False, category=None, accessing_obj=None, default_access=True): """Remove attribute or a list of attributes from object. If accessing_obj is given, will check against the 'attredit' lock. If not given, this check is skipped. """ keys = make_iter(key) category_cond = Q(db_category__iexact=category) if category else Q() for attrkey in keys: matches = _GA(self.obj, self._m2m_fieldname).filter(Q(db_key__iexact=attrkey) & Q()) if not matches and raise_exception: raise AttributeError for attr in matches: if accessing_obj and not attr.access(accessing_obj, self._attredit, default=default_access): continue del_attr_cache(self.obj, attr.db_key) attr.delete() def clear(self, category=None, accessing_obj=None, default_access=True): """ Remove all Attributes on this object. If accessing_obj is given, check the 'attredit' lock on each Attribute before continuing. If not given, skip check. """ if category==None: all_attr = _GA(self.obj, self._m2m_fieldname).all() else: all_attrs = _GA(self.obj, self._m2m_fieldname).filter(db_category=category) for attr in all_attrs: if accessing_obj and not attr.access(accessing_obj, self._attredit, default=default_access): continue del_attr_cache(self.obj, attr.db_key) attr.delete() def all(self, category=None, accessing_obj=None, default_access=True): """ Return all Attribute objects on this object. If accessing_obj is given, check the "attrread" lock on each attribute before returning them. If not given, this check is skipped. """ if category==None: all_attrs = _GA(self.obj, self._m2m_fieldname).all() else: all_attrs = _GA(self.obj, self._m2m_fieldname).filter(db_category=category) if accessing_obj: return [attr for attr in all_attrs if attr.access(accessing_obj, self._attrread, default=default_access)] else: return list(all_attrs) class NickHandler(AttributeHandler): """ Handles the addition and removal of Nicks (uses Attributes' strvalue and category fields) """ def has(self, key, category="inputline"): categry = "nick_%s" % category return super(NickHandler, self).has(key, category=category) def add(self, key, replacement, category="inputline", **kwargs): "Add a new nick" category = "nick_%s" % category super(NickHandler, self).add(key, replacement, category=category, strattr=True, **kwargs) def get(self, key, category="inputline", **kwargs): "Get the replacement value matching the given key and category" category = "nick_%s" % category return super(NickHandler, self).get(key, category=category, strattr=True, **kwargs) def remove(self, key, category="inputline", **kwargs): "Remove Nick with matching category" category = "nick_%s" % category super(NickHandler, self).remove(key, category=category, **kwargs) #------------------------------------------------------------ # # Tags # #------------------------------------------------------------ class Tag(models.Model): """ Tags are quick markers for objects in-game. An typeobject can have any number of tags, stored via its db_tags property. Tagging similar objects will make it easier to quickly locate the group later (such as when implementing zones). The main advantage of tagging as opposed to using Attributes is speed; a tag is very limited in what data it can hold, and the tag key+category is indexed for efficient lookup in the database. Tags are shared between objects - a new tag is only created if the key+category combination did not previously exist, making them unsuitable for storing object-related data (for this a full Attribute should be used). The 'db_data' field is intended as a documentation field for the tag itself, such as to document what this tag+category stands for and display that in a web interface or similar. The main default use for Tags is to implement Aliases for objects. this uses the 'aliases' tag category, which is also checked by the default search functions of Evennia to allow quick searches by alias. """ db_key = models.CharField('key', max_length=255, null=True, help_text="tag identifier", db_index=True) db_category = models.CharField('category', max_length=64, null=True, help_text="tag category", db_index=True) db_data = models.TextField('data', null=True, blank=True, help_text="optional data field with extra information. This is not searched for.") objects = managers.TagManager() class Meta: "Define Django meta options" verbose_name = "Tag" unique_together =(('db_key', 'db_category'),) index_together = (('db_key', 'db_category'),) def __unicode__(self): return u"%s" % self.db_key def __str__(self): return str(self.db_key) # # Handlers making use of the Tags model # class TagHandler(object): """ Generic tag-handler. Accessed via TypedObject.tags. """ _m2m_fieldname = "db_tags" _base_category = "" def __init__(self, obj, category_prefix=""): """ Tags are stored internally in the TypedObject.db_tags m2m field using the category """ self.obj = obj self.prefix = "%s%s" % (category_prefix.strip().lower() if category_prefix else "", self._base_category) def add(self, tag, category=None, data=None): "Add a new tag to the handler. Tag is a string or a list of strings." for tagstr in make_iter(tag): tagstr = tagstr.strip().lower() if tagstr!=None else None category = "%s%s" % (self.prefix, category.strip().lower()) if category!=None else None data = str(data) if data!=None else None # this will only create tag if no matches existed beforehand (it will overload # data on an existing tag since that is not considered part of making the tag unique) tagobj = Tag.objects.create_tag(key=tagstr, category=category, data=data) #print tagstr #print tagobj _GA(self.obj, self._m2m_fieldname).add(tagobj) def get(self, key, category="", return_obj=False): "Get the data field for the given tag or list of tags. If return_obj=True, return the matching Tag objects instead." ret = [] category = "%s%s" % (self.prefix, category.strip().lower()) if category!=None else None for keystr in make_iter(key): ret.expand(_GA(self.obj, self._m2m_fieldname).filter(db_key__iexact=keystr, db_category__iexact=category)) ret = ret if return_obj else [to_str(tag.db_data) for tag in ret] return ret[0] if len(ret)==1 else ret def remove(self, tag, category=None): "Remove a tag from the handler" for tag in make_iter(tag): if not tag or tag.strip(): # we don't allow empty tags continue tag = tag.strip().lower() if tag!=None else None category = "%s%s" % (self.prefix, category.strip().lower()) if category!=None else None #TODO This does not delete the tag object itself. Maybe it should do that when no # objects reference the tag anymore? tagobj = self.obj.db_tags.filter(db_key=tag, db_category=category) if tagobj: _GA(self.obj, self._m2m_fieldname).remove(tagobj[0]) def clear(self): "Remove all tags from the handler" _GA(self.obj, self._m2m_fieldname).clear() def all(self): "Get all tags in this handler" return [p[0] for p in _GA(self.obj, self._m2m_fieldname).all().values_list("db_key")] def __str__(self): return ",".join(self.all()) def __unicode(self): return u",".join(self.all()) class AliasHandler(TagHandler): _base_category = "alias" class PermissionHandler(TagHandler): _base_category = "permission" #------------------------------------------------------------ # # Typed Objects # #------------------------------------------------------------ class TypedObject(SharedMemoryModel): """ Abstract Django model. This is the basis for a typed object. It also contains all the mechanics for managing connected attributes. The TypedObject has the following properties: key - main name name - alias for key typeclass_path - the path to the decorating typeclass typeclass - auto-linked typeclass date_created - time stamp of object creation permissions - perm strings dbref - #id of object db - persistent attribute storage ndb - non-persistent attribute storage """ # # TypedObject Database Model setup # # # These databse fields are all accessed and set using their corresponding properties, # named same as the field, but without the db_* prefix (no separate save() call is needed) # Main identifier of the object, for searching. Is accessed with self.key or self.name db_key = models.CharField('key', max_length=255, db_index=True) # This is the python path to the type class this object is tied to the type class is what defines what kind of Object this is) db_typeclass_path = models.CharField('typeclass', max_length=255, null=True, help_text="this defines what 'type' of entity this is. This variable holds a Python path to a module with a valid Evennia Typeclass.") # Creation date. This is not changed once the object is created. db_date_created = models.DateTimeField('creation date', editable=False, auto_now_add=True) # Permissions (access these through the 'permissions' property) #db_permissions = models.CharField('permissions', max_length=255, blank=True, # help_text="a comma-separated list of text strings checked by in-game locks. They are often used for hierarchies, such as letting a Player have permission 'Wizards', 'Builders' etc. Character objects use 'Players' by default. Most other objects don't have any permissions.") # Lock storage db_lock_storage = models.TextField('locks', blank=True, help_text="locks limit access to an entity. A lock is defined as a 'lock string' on the form 'type:lockfunctions', defining what functionality is locked and how to determine access. Not defining a lock means no access is granted.") # many2many relationships db_attributes = models.ManyToManyField(Attribute, null=True, help_text='attributes on this object. An attribute can hold any pickle-able python object (see docs for special cases).') db_tags = models.ManyToManyField(Tag, null=True, help_text='tags on this object. Tags are simple string markers to identify, group and alias objects.') # Database manager objects = managers.TypedObjectManager() # quick on-object typeclass cache for speed _cached_typeclass = None # lock handler self.locks def __init__(self, *args, **kwargs): "We must initialize the parent first - important!" super(SharedMemoryModel, self).__init__(*args, **kwargs) #SharedMemoryModel.__init__(self, *args, **kwargs) _SA(self, "dbobj", self) # this allows for self-reference _SA(self, "locks", LockHandler(self)) _SA(self, "permissions", PermissionHandler(self)) class Meta: """ Django setup info. """ abstract = True verbose_name = "Evennia Database Object" ordering = ['-db_date_created', 'id', 'db_typeclass_path', 'db_key'] # wrapper # Wrapper properties to easily set database fields. These are # @property decorators that allows to access these fields using # normal python operations (without having to remember to save() # etc). So e.g. a property 'attr' has a get/set/del decorator # defined that allows the user to do self.attr = value, # value = self.attr and del self.attr respectively (where self # is the object in question). # key property (wraps db_key) #@property #def __key_get(self): # "Getter. Allows for value = self.key" # #return _GA(self, "db_key") # return get_field_cache(self, "key") ##@key.setter #def __key_set(self, value): # "Setter. Allows for self.key = value" # set_field_cache(self, "key", value) ##@key.deleter #def __key_del(self): # "Deleter. Allows for del self.key" # raise Exception("Cannot delete objectdb key!") #key = property(__key_get, __key_set, __key_del) # name property (alias to self.key) def __name_get(self): return self.key def __name_set(self, value): self.key = value def __name_del(self): raise Exception("Cannot delete name") name = property(__name_get, __name_set, __name_del) # typeclass_path property - we manage this separately. #@property #def __typeclass_path_get(self): # "Getter. Allows for value = self.typeclass_path" # return _GA(self, "db_typeclass_path") ##@typeclass_path.setter #def __typeclass_path_set(self, value): # "Setter. Allows for self.typeclass_path = value" # _SA(self, "db_typeclass_path", value) # update_fields = ["db_typeclass_path"] if _GA(self, "_get_pk_val")(_GA(self, "_meta")) is not None else None # _GA(self, "save")(update_fields=update_fields) ##@typeclass_path.deleter #def __typeclass_path_del(self): # "Deleter. Allows for del self.typeclass_path" # self.db_typeclass_path = "" # _GA(self, "save")(update_fields=["db_typeclass_path"]) #typeclass_path = property(__typeclass_path_get, __typeclass_path_set, __typeclass_path_del) # date_created property #@property #def __date_created_get(self): # "Getter. Allows for value = self.date_created" # return get_field_cache(self, "date_created") ##@date_created.setter #def __date_created_set(self, value): # "Setter. Allows for self.date_created = value" # raise Exception("Cannot change date_created!") ##@date_created.deleter #def __date_created_del(self): # "Deleter. Allows for del self.date_created" # raise Exception("Cannot delete date_created!") #date_created = property(__date_created_get, __date_created_set, __date_created_del) # permissions property #@property #def __permissions_get(self): # "Getter. Allows for value = self.name. Returns a list of permissions." # perms = get_field_cache(self, "permissions") # if perms: # return [perm.strip() for perm in perms.split(',')] # return [] ##@permissions.setter #def __permissions_set(self, value): # "Setter. Allows for self.name = value. Stores as a comma-separated string." # value = ",".join([utils.to_unicode(val).strip() for val in make_iter(value)]) # set_field_cache(self, "permissions", value) ##@permissions.deleter #def __permissions_del(self): # "Deleter. Allows for del self.name" # self.db_permissions = "" # self.save() # del_field_cache(self, "permissions") #permissions = property(__permissions_get, __permissions_set, __permissions_del) # lock_storage property (wraps db_lock_storage) #@property #def __lock_storage_get(self): # "Getter. Allows for value = self.lock_storage" # return get_field_cache(self, "lock_storage") ##@lock_storage.setter #def __lock_storage_set(self, value): # """Saves the lock_storage. This is usually not called directly, but through self.lock()""" # set_field_cache(self, "lock_storage", value) ##@lock_storage.deleter #def __lock_storage_del(self): # "Deleter is disabled. Use the lockhandler.delete (self.lock.delete) instead""" # logger.log_errmsg("Lock_Storage (on %s) cannot be deleted. Use obj.lock.delete() instead." % self) #lock_storage = property(__lock_storage_get, __lock_storage_set, __lock_storage_del) # # # TypedObject main class methods and properties # # # these are identifiers for fast Attribute access and caching _typeclass_paths = settings.OBJECT_TYPECLASS_PATHS def __eq__(self, other): return other and hasattr(other, 'dbid') and self.dbid == other.dbid def __str__(self): return smart_str("%s" % _GA(self, "db_key")) def __unicode__(self): return u"%s" % _GA(self, "db_key") def __getattribute__(self, propname): """ Will predominantly look for an attribute on this object, but if not found we will check if it might exist on the typeclass instead. Since the typeclass refers back to the databaseobject as well, we have to be very careful to avoid loops. """ try: return _GA(self, propname) except AttributeError: if propname.startswith('_'): # don't relay private/special varname lookups to the typeclass raise AttributeError("private property %s not found on db model (typeclass not searched)." % propname) # check if the attribute exists on the typeclass instead # (we make sure to not incur a loop by not triggering the # typeclass' __getattribute__, since that one would # try to look back to this very database object.) return _GA(_GA(self, 'typeclass'), propname) def _hasattr(self, obj, attrname): """ Loop-safe version of hasattr, to avoid running a lookup that will be rerouted up the typeclass. Returns True/False. """ try: _GA(obj, attrname) return True except AttributeError: return False #@property def __dbid_get(self): """ Caches and returns the unique id of the object. Use this instead of self.id, which is not cached. """ dbid = get_prop_cache(self, "_dbid") if not dbid: dbid = _GA(self, "id") set_prop_cache(self, "_dbid", dbid) return dbid def __dbid_set(self, value): raise Exception("dbid cannot be set!") def __dbid_del(self): raise Exception("dbid cannot be deleted!") dbid = property(__dbid_get, __dbid_set, __dbid_del) #@property def __dbref_get(self): """ Returns the object's dbref on the form #NN. """ return "#%s" % _GA(self, "_TypedObject__dbid_get")() def __dbref_set(self): raise Exception("dbref cannot be set!") def __dbref_del(self): raise Exception("dbref cannot be deleted!") dbref = property(__dbref_get, __dbref_set, __dbref_del) # typeclass property #@property def __typeclass_get(self): """ Getter. Allows for value = self.typeclass. The typeclass is a class object found at self.typeclass_path; it allows for extending the Typed object for all different types of objects that the game needs. This property handles loading and initialization of the typeclass on the fly. Note: The liberal use of _GA and __setattr__ (instead of normal dot notation) is due to optimization: it avoids calling the custom self.__getattribute__ more than necessary. """ path = _GA(self, "typeclass_path") typeclass = _GA(self, "_cached_typeclass") try: if typeclass and _GA(typeclass, "path") == path: # don't call at_init() when returning from cache return typeclass except AttributeError: pass errstring = "" if not path: # this means we should get the default obj without giving errors. return _GA(self, "_get_default_typeclass")(cache=True, silent=True, save=True) else: # handle loading/importing of typeclasses, searching all paths. # (self._typeclass_paths is a shortcut to settings.TYPECLASS_*_PATHS # where '*' is either OBJECT, SCRIPT or PLAYER depending on the typed # entities). typeclass_paths = [path] + ["%s.%s" % (prefix, path) for prefix in _GA(self, '_typeclass_paths')] for tpath in typeclass_paths: # try to import and analyze the result typeclass = _GA(self, "_path_import")(tpath) #print "typeclass:",typeclass,tpath if callable(typeclass): # we succeeded to import. Cache and return. _SA(self, "typeclass_path", tpath) typeclass = typeclass(self) _SA(self, "_cached_typeclass", typeclass) try: typeclass.at_init() except AttributeError: logger.log_trace("\n%s: Error initializing typeclass %s. Using default." % (self, tpath)) break except Exception: logger.log_trace() return typeclass elif hasattr(typeclass, '__file__'): errstring += "\n%s seems to be just the path to a module. You need" % tpath errstring += " to specify the actual typeclass name inside the module too." else: errstring += "\n%s" % typeclass # this will hold a growing error message. # If we reach this point we couldn't import any typeclasses. Return default. It's up to the calling # method to use e.g. self.is_typeclass() to detect that the result is not the one asked for. _GA(self, "_display_errmsg")(errstring) _SA(self, "typeclass_lasterrmsg", errstring) return _GA(self, "_get_default_typeclass")(cache=False, silent=False, save=False) #@typeclass.deleter def __typeclass_del(self): "Deleter. Disallow 'del self.typeclass'" raise Exception("The typeclass property should never be deleted, only changed in-place!") # typeclass property typeclass = property(__typeclass_get, fdel=__typeclass_del) # the last error string will be stored here for accessing methods to access. # It is set by _display_errmsg, which will print to log if error happens # during server startup. typeclass_last_errmsg = "" def _path_import(self, path): """ Import a class from a python path of the form src.objects.object.Object """ errstring = "" if not path: # this needs not be bad, it just means # we should use defaults. return None try: modpath, class_name = path.rsplit('.', 1) module = __import__(modpath, fromlist=["none"]) return module.__dict__[class_name] except ImportError: trc = sys.exc_traceback if not trc.tb_next: # we separate between not finding the module, and finding a buggy one. errstring = "Typeclass not found trying path '%s'." % path else: # a bug in the module is reported normally. trc = traceback.format_exc() errstring = "\n%sError importing '%s'." % (trc, path) except (ValueError, TypeError): errstring = "Malformed typeclass path '%s'." % path except KeyError: errstring = "No class '%s' was found in module '%s'." errstring = errstring % (class_name, modpath) except Exception: trc = traceback.format_exc() errstring = "\n%sException importing '%s'." % (trc, path) # return the error. return errstring def _display_errmsg(self, message): """ Helper function to display error. """ if ServerConfig.objects.conf("server_starting_mode"): print message.strip() else: _SA(self, "typeclass_last_errmsg", message.strip()) return def _get_default_typeclass(self, cache=False, silent=False, save=False): """ This is called when a typeclass fails to load for whatever reason. Overload this in different entities. Default operation is to load a default typeclass. """ defpath = _GA(self, "_default_typeclass_path") typeclass = _GA(self, "_path_import")(defpath) # if not silent: # #errstring = "\n\nUsing Default class '%s'." % defpath # _GA(self, "_display_errmsg")(errstring) if not callable(typeclass): # if typeclass still doesn't exist at this point, we're in trouble. # fall back to hardcoded core class which is wrong for e.g. scripts/players etc. failpath = defpath defpath = "src.objects.objects.Object" typeclass = _GA(self, "_path_import")(defpath) if not silent: #errstring = " %s\n%s" % (typeclass, errstring) errstring = " Default class '%s' failed to load." % failpath errstring += "\n Using Evennia's default class '%s'." % defpath _GA(self, "_display_errmsg")(errstring) if not callable(typeclass): # if this is still giving an error, Evennia is wrongly configured or buggy raise Exception("CRITICAL ERROR: The final fallback typeclass %s cannot load!!" % defpath) typeclass = typeclass(self) if save: _SA(self, 'db_typeclass_path', defpath) _GA(self, 'save')() if cache: _SA(self, "_cached_db_typeclass_path", defpath) _SA(self, "_cached_typeclass", typeclass) try: typeclass.at_init() except Exception: logger.log_trace() return typeclass def is_typeclass(self, typeclass, exact=False): """ Returns true if this object has this type OR has a typeclass which is an subclass of the given typeclass. This operates on the actually loaded typeclass (this is important since a failing typeclass may instead have its default currently loaded) typeclass - can be a class object or the python path to such an object to match against. exact - returns true only if the object's type is exactly this typeclass, ignoring parents. """ try: typeclass = _GA(typeclass, "path") except AttributeError: pass typeclasses = [typeclass] + ["%s.%s" % (path, typeclass) for path in _GA(self, "_typeclass_paths")] if exact: current_path = _GA(self.typeclass, "path") #"_GA(self, "_cached_db_typeclass_path") return typeclass and any((current_path == typec for typec in typeclasses)) else: # check parent chain return any((cls for cls in self.typeclass.__class__.mro() if any(("%s.%s" % (_GA(cls,"__module__"), _GA(cls,"__name__")) == typec for typec in typeclasses)))) def delete(self, *args, **kwargs): """ Type-level cleanup """ flush_attr_cache() super(TypedObject, self).delete(*args, **kwargs) # # Object manipulation methods # # def swap_typeclass(self, new_typeclass, clean_attributes=False, no_default=True): """ This performs an in-situ swap of the typeclass. This means that in-game, this object will suddenly be something else. Player will not be affected. To 'move' a player to a different object entirely (while retaining this object's type), use self.player.swap_object(). Note that this might be an error prone operation if the old/new typeclass was heavily customized - your code might expect one and not the other, so be careful to bug test your code if using this feature! Often its easiest to create a new object and just swap the player over to that one instead. Arguments: new_typeclass (path/classobj) - type to switch to clean_attributes (bool/list) - will delete all attributes stored on this object (but not any of the database fields such as name or location). You can't get attributes back, but this is often the safest bet to make sure nothing in the new typeclass clashes with the old one. If you supply a list, only those named attributes will be cleared. no_default - if this is active, the swapper will not allow for swapping to a default typeclass in case the given one fails for some reason. Instead the old one will be preserved. Returns: boolean True/False depending on if the swap worked or not. """ if callable(new_typeclass): # this is an actual class object - build the path cls = new_typeclass new_typeclass = "%s.%s" % (cls.__module__, cls.__name__) else: new_typeclass = "%s" % to_str(new_typeclass) # Try to set the new path # this will automatically save to database old_typeclass_path = self.typeclass_path _SA(self, "typeclass_path", new_typeclass.strip()) # this will automatically use a default class if # there is an error with the given typeclass. new_typeclass = self.typeclass if self.typeclass_path != new_typeclass.path and no_default: # something went wrong; the default was loaded instead, # and we don't allow that; instead we return to previous. _SA(self, "typeclass_path", old_typeclass_path) return False if clean_attributes: # Clean out old attributes if is_iter(clean_attributes): for attr in clean_attributes: self.attr(attr, delete=True) for nattr in clean_attributes: if hasattr(self.ndb, nattr): self.nattr(nattr, delete=True) else: #print "deleting attrs ..." for attr in self.get_all_attributes(): attr.delete() for nattr in self.ndb.all: del nattr # run hooks for this new typeclass new_typeclass.basetype_setup() new_typeclass.at_object_creation() return True # # Lock / permission methods # def access(self, accessing_obj, access_type='read', default=False): """ Determines if another object has permission to access. accessing_obj - object trying to access this one access_type - type of access sought default - what to return if no lock of access_type was found """ return self.locks.check(accessing_obj, access_type=access_type, default=default) def check_permstring(self, permstring): """ This explicitly checks if we hold particular permission without involving any locks. """ if hasattr(self, "player"): if self.player and self.player.is_superuser: return True else: if self.is_superuser: return True if not permstring: return False perm = permstring.lower() perms = [p.lower() for p in self.permissions.all()] if perm in perms: # simplest case - we have a direct match return True if perm in _PERMISSION_HIERARCHY: # check if we have a higher hierarchy position ppos = _PERMISSION_HIERARCHY.index(perm) return any(True for hpos, hperm in enumerate(_PERMISSION_HIERARCHY) if hperm in perms and hpos > ppos) return False def flush_from_cache(self): """ Flush this object instance from cache, forcing an object reload. Note that this will kill all temporary attributes on this object since it will be recreated as a new Typeclass instance. """ self.__class__.flush_cached_instance(self) # # Non-persistent (ndb) storage # #@property ndb def __ndb_get(self): """ A non-attr_obj store (ndb: NonDataBase). Everything stored to this is guaranteed to be cleared when a server is shutdown. Syntax is same as for the _get_db_holder() method and property, e.g. obj.ndb.attr = value etc. """ try: return self._ndb_holder except AttributeError: class NdbHolder(object): "Holder for storing non-attr_obj attributes." def get_all(self): return [val for val in self.__dict__.keys() if not val.startswith('_')] all = property(get_all) def __getattribute__(self, key): # return None if no matching attribute was found. try: return _GA(self, key) except AttributeError: return None def __setattr__(self, key, value): # hook the oob handler here #call_ndb_hooks(self, key, value) _SA(self, key, value) self._ndb_holder = NdbHolder() return self._ndb_holder #@ndb.setter def __ndb_set(self, value): "Stop accidentally replacing the db object" string = "Cannot assign directly to ndb object! " string = "Use ndb.attr=value instead." raise Exception(string) #@ndb.deleter def __ndb_del(self): "Stop accidental deletion." raise Exception("Cannot delete the ndb object!") ndb = property(__ndb_get, __ndb_set, __ndb_del) #def nattr(self, attribute_name=None, value=None, delete=False): # """ # This allows for assigning non-persistent data on the object using # a method call. Will return None if trying to access a non-existing property. # """ # if attribute_name == None: # # act as a list method # if callable(self.ndb.all): # return self.ndb.all() # else: # return [val for val in self.ndb.__dict__.keys() # if not val.startswith['_']] # elif delete == True: # if hasattr(self.ndb, attribute_name): # _DA(_GA(self, "ndb"), attribute_name) # elif value == None: # # act as a getter. # if hasattr(self.ndb, attribute_name): # _GA(_GA(self, "ndb"), attribute_name) # else: # return None # else: # # act as a setter # _SA(self.ndb, attribute_name, value) # # Attribute handler methods - DEPRECATED! # # # Fully attr_obj attributes. You usually access these # through the obj.db.attrname method. # Helper methods for attr_obj attributes def has_attribute(self, attribute_name): """ See if we have an attribute set on the object. attribute_name: (str) The attribute's name. """ logger.log_depmsg("obj.has_attribute() is deprecated. Use obj.attributes.has().") return _GA(self, "attributes").has(attribute_name) def set_attribute(self, attribute_name, new_value=None, lockstring=""): """ Sets an attribute on an object. Creates the attribute if need be. attribute_name: (str) The attribute's name. new_value: (python obj) The value to set the attribute to. If this is not a str, the object will be stored as a pickle. lockstring - this sets an access restriction on the attribute object. Note that this is normally NOT checked - use the secureattr() access method below to perform access-checked modification of attributes. Lock types checked by secureattr are 'attrread','attredit','attrcreate'. """ logger.log_depmsg("obj.set_attribute() is deprecated. Use obj.db.attr=value or obj.attributes.add().") _GA(self, "attributes").add(attribute_name, new_value, lockstring=lockstring) def get_attribute_obj(self, attribute_name, default=None): """ Get the actual attribute object named attribute_name """ logger.log_depmsg("obj.get_attribute_obj() is deprecated. Use obj.attributes.get(..., return_obj=True)") return _GA(self, "attributes").get(attribute_name, default=default, return_obj=True) def get_attribute(self, attribute_name, default=None, raise_exception=False): """ Returns the value of an attribute on an object. You may need to type cast the returned value from this function since the attribute can be of any type. Returns default if no match is found. attribute_name: (str) The attribute's name. default: What to return if no attribute is found raise_exception (bool) - raise an exception if no object exists instead of returning default. """ logger.log_depmsg("obj.get_attribute() is deprecated. Use obj.db.attr or obj.attributes.get().") return _GA(self, "attributes").get(attribute_name, default=default, raise_exception=raise_exception) def del_attribute(self, attribute_name, raise_exception=False): """ Removes an attribute entirely. attribute_name: (str) The attribute's name. raise_exception (bool) - raise exception if attribute to delete could not be found """ logger.log_depmsg("obj.del_attribute() is deprecated. Use del obj.db.attr or obj.attributes.remove().") _GA(self, "attributes").remove(attribute_name, raise_exception=raise_exception) def get_all_attributes(self): """ Returns all attributes defined on the object. """ logger.log_depmsg("obj.get_all_attributes() is deprecated. Use obj.db.all() or obj.attributes.all().") return _GA(self, "attributes").all() def attr(self, attribute_name=None, value=None, delete=False): """ This is a convenient wrapper for get_attribute, set_attribute, del_attribute and get_all_attributes. If value is None, attr will act like a getter, otherwise as a setter. set delete=True to delete the named attribute. Note that you cannot set the attribute value to None using this method. Use set_attribute. """ logger.log_depmsg("obj.attr() is deprecated. Use handlers obj.db or obj.attributes.") if attribute_name == None: # act as a list method return _GA(self, "attributes").all() elif delete == True: _GA(self, "attributes").remove(attribute_name) elif value == None: # act as a getter. return _GA(self, "attributes").get(attribute_name) else: # act as a setter self._GA(self, "attributes").add(attribute_name, value) def secure_attr(self, accessing_object, attribute_name=None, value=None, delete=False, default_access_read=True, default_access_edit=True, default_access_create=True): """ This is a version of attr that requires the accessing object as input and will use that to check eventual access locks on the Attribute before allowing any changes or reads. In the cases when this method wouldn't return, it will return True for a successful operation, None otherwise. locktypes checked on the Attribute itself: attrread - control access to reading the attribute value attredit - control edit/delete access locktype checked on the object on which the Attribute is/will be stored: attrcreate - control attribute create access (this is checked *on the object* not on the Attribute!) default_access_* defines which access is assumed if no suitable lock is defined on the Atttribute. """ logger.log_depmsg("obj.secure_attr() is deprecated. Use obj.attributes methods, giving accessing_obj keyword.") if attribute_name == None: return _GA(self, "attributes").all(accessing_obj=accessing_object, default_access=default_access_read) elif delete == True: # act as deleter _GA(self, "attributes").remove(attribute_name, accessing_obj=accessing_object, default_access=default_access_edit) elif value == None: # act as getter return _GA(self, "attributes").get(attribute_name, accessing_obj=accessing_object, default_access=default_access_read) else: # act as setter attr = _GA(self, "attributes").get(attribute_name, return_obj=True) if attr: # attribute already exists _GA(self, "attributes").add(attribute_name, value, accessing_obj=accessing_object, default_access=default_access_edit) else: # creating a new attribute - check access on storing object! _GA(self, "attributes").add(attribute_name, value, accessing_obj=accessing_object, default_access=default_access_create) #@property def __db_get(self): """ A second convenience wrapper for the the attribute methods. It allows for the syntax obj.db.attrname = value and value = obj.db.attrname and del obj.db.attrname and all_attr = obj.db.all (unless there is no attribute named 'all', in which case that will be returned instead). """ try: return self._db_holder except AttributeError: class DbHolder(object): "Holder for allowing property access of attributes" def __init__(self, obj): _SA(self, 'obj', obj) _SA(self, "attrhandler", _GA(_GA(self, "obj"), "attributes")) def __getattribute__(self, attrname): if attrname == 'all': # we allow to overload our default .all attr = _GA(self, "attrhandler").get("all") if attr: return attr return _GA(self, 'all') return _GA(self, "attrhandler").get(attrname) def __setattr__(self, attrname, value): _GA(self, "attrhandler").add(attrname, value) def __delattr__(self, attrname): _GA(self, "attrhandler").remove(attrname) def get_all(self): return _GA(self, "attrhandler").all() all = property(get_all) self._db_holder = DbHolder(self) return self._db_holder #@db.setter def __db_set(self, value): "Stop accidentally replacing the db object" string = "Cannot assign directly to db object! " string += "Use db.attr=value instead." raise Exception(string) #@db.deleter def __db_del(self): "Stop accidental deletion." raise Exception("Cannot delete the db object!") db = property(__db_get, __db_set, __db_del) # connect to attribute cache signal m2m_changed.connect(post_attr_update, sender=TypedObject.db_attributes.through)