def __getattr__(self, key):
if is_instrumented(self, key):
return get_attribute(self, key)
else:
try:
return self._goofy_dict[key]
except KeyError:
raise AttributeError(key)
def __getattr__(self, key):
if is_instrumented(self, key):
return get_attribute(self, key)
else:
try:
return self._goofy_dict[key]
except KeyError:
raise AttributeError(key)
def update_by_ma(self, schema, instance, commit=True):
"""根据marshmallow以及SQLa实例更新
:param schema: Schema Schema类或实例
:param instance: object Model对象
:param commit: bool 是否commit
此方法用以更新Sqla实例的字段，基于一个marshmallow类或实例，
根据marshmallow类的load字段加载。由于需要一个临时变量的
instance，对于需要同时处理复杂relationship的子关系需要增
加指定active_history=True来跟踪变化以维持正确的加载。
形如：
>>> class Remote(Model):
id = Column(Integer(), primary_key=True)
name = Column(String(80))
>>> class Local(Model):
id = Column(Integer(), primary_key=True)
remote_id = Column(Integer())
remote = relationship("Remote", active_history=True,
backref=backref('local', active_history=True)
)
在这里需要修改Remote中name以及关系时。
"""
from sqlalchemy.orm.attributes import (
get_attribute,
del_attribute,
set_attribute,
)
from marshmallow import Schema
if not isinstance(schema, Schema):
schema = schema()
db.session.add(instance)
loadable_fields = [
k for k, v in schema.fields.items() if not v.dump_only
]
with db.session.no_autoflush:
for field in loadable_fields:
set_attribute(self, field, get_attribute(instance, field))
del_attribute(instance, field)
db.session.expunge(instance)
self.save(commit)
def before_insert(self, mapper, connection, instance):
fields = [get_attribute(instance, f) for f in self.generate_from]
table = mapper.columns[self.slugfield].table
column = table.c[self.slugfield]
assert isinstance(column.type, (db.Unicode, db.String))
max_length = column.type.length
# filter out fields with no value as we cannot join them they are
# not relevant for slug generation.
fields = ifilter(None, fields)
slug = self.separator.join(imap(gen_ascii_slug, fields))
# strip the string if max_length is applied
slug = slug[:max_length-4] if max_length is not None else slug
set_attribute(instance, self.slugfield,
find_next_increment(getattr(instance.__class__, self.slugfield),
slug, max_length))
return orm.EXT_CONTINUE
def before_insert(self, mapper, connection, instance):
fields = [get_attribute(instance, f) for f in self.generate_from]
table = mapper.columns[self.slugfield].table
column = table.c[self.slugfield]
assert isinstance(column.type, (db.Unicode, db.String))
max_length = column.type.length
# filter out fields with no value as we cannot join them they are
# not relevant for slug generation.
fields = ifilter(None, fields)
slug = self.separator.join(imap(gen_ascii_slug, fields))
# strip the string if max_length is applied
slug = slug[:max_length - 4] if max_length is not None else slug
set_attribute(
instance, self.slugfield,
find_next_increment(getattr(instance.__class__, self.slugfield),
slug, max_length))
return orm.EXT_CONTINUE
def create_version(obj, session, before_flush=False, deleted=False, new=False):
obj_mapper = object_mapper(obj)
history_mapper = obj.__history_mapper__
history_cls = history_mapper.class_
obj_state = attributes.instance_state(obj)
attr = {}
obj_changed = False
for om, hm in zip(obj_mapper.iterate_to_root(), history_mapper.iterate_to_root()):
if hm.single:
continue
for hist_col in hm.local_table.c:
if hist_col.key in ["version", "created"]:
continue
obj_col = om.local_table.c[hist_col.key]
# get the value of the
# attribute based on the MapperProperty related to the
# mapped column. this will allow usage of MapperProperties
# that have a different keyname than that of the mapped column.
try:
prop = obj_mapper.get_property_by_column(obj_col)
except UnmappedColumnError:
# in the case of single table inheritance, there may be
# columns on the mapped table intended for the subclass only.
# the "unmapped" status of the subclass column on the
# base class is a feature of the declarative module as of sqla 0.5.2.
continue
# expired object attributes and also deferred cols might not be in the
# dict. force it to load no matter what by using getattr().
if prop.key not in obj_state.dict:
getattr(obj, prop.key)
a, u, d = attributes.get_history(obj, prop.key)
c = attributes.get_attribute(obj, prop.key)
if d:
attr[hist_col.key] = c
obj_changed = True
elif u:
attr[hist_col.key] = c
else:
# if the attribute had no value.
attr[hist_col.key] = c
obj_changed = True
if not obj_changed:
# not changed, but we have relationships. OK
# check those too
for prop in obj_mapper.iterate_properties:
if isinstance(prop, RelationshipProperty) and attributes.get_history(obj, prop.key).has_changes():
obj_changed = True
break
if not obj_changed and not deleted and not new:
return
if before_flush:
obj.version += 1
return
attr["version"] = obj.version
hist = history_cls()
for key, value in attr.iteritems():
setattr(hist, key, value)
if deleted:
action = "delete"
elif new:
action = "create"
else:
action = "update"
from humusha.apps.words.models import Change
change = Change(
row_id=obj.id, word_id=obj.dependant_word_id, version=obj.version, model=obj.__class__.__name__, action=action
)
session.add(change)
# if new:
# hist.version = 0
session.add(hist)
obj.version += 1
session.add(obj)
def _setattr_from_instance(self, fields: List[str], instance: db.Model):
with db.session.no_autoflush:
for field in fields:
set_attribute(self, field, get_attribute(instance, field))
del_attribute(instance, field)
def _setattr_from_instance(self, fields: List[str], instance: _M) -> None:
with self.session().no_autoflush:
for field in fields:
set_attribute(self.instance(), field, get_attribute(instance, field))
del_attribute(instance, field)
