dnl.re dnl.re - 18 days ago 14
Python Question

overriding write() method in odoo 8 results in RuntimeError: maximum recursion depth exceeded

This seems to be a significant simple problem, but somehow I cant find a solution.

As I press the save button the write method will be executed. I want to change a value (or call a function) of the current model every time the write method is called, so I have overridden the write() method of my model as

@api.multi
def write(self, vals):
self.flaeche = 37
return super(lager, self).write(vals)


(the model is
lager.py
and the field is
flaeche = fields.Float(string=u"Fläche (m²)")
)

The Error:
RuntimeError: maximum recursion depth exceeded


Traceback (most recent call last):
File "/home/tertia/workspace/odoo8/openerp/http.py", line 530, in _handle_exception
return super(JsonRequest, self)._handle_exception(exception)
File "/home/tertia/workspace/odoo8/openerp/http.py", line 567, in dispatch
result = self._call_function(**self.params)
File "/home/tertia/workspace/odoo8/openerp/http.py", line 303, in _call_function
return checked_call(self.db, *args, **kwargs)
File "/home/tertia/workspace/odoo8/openerp/service/model.py", line 113, in wrapper
return f(dbname, *args, **kwargs)
File "/home/tertia/workspace/odoo8/openerp/http.py", line 300, in checked_call
return self.endpoint(*a, **kw)
File "/home/tertia/workspace/odoo8/openerp/http.py", line 796, in __call__
return self.method(*args, **kw)
File "/home/tertia/workspace/odoo8/openerp/http.py", line 396, in response_wrap
response = f(*args, **kw)
File "/home/tertia/workspace/odoo8/openerp/addons/web/controllers/main.py", line 936, in call_kw
return self._call_kw(model, method, args, kwargs)
File "/home/tertia/workspace/odoo8/openerp/addons/web/controllers/main.py", line 928, in _call_kw
return getattr(request.registry.get(model), method)(request.cr, request.uid, *args, **kwargs)
File "/home/tertia/workspace/odoo8/openerp/api.py", line 241, in wrapper
return old_api(self, *args, **kwargs)
File "/home/tertia/workspace/odoo8/openerp/api.py", line 363, in old_api
result = method(recs, *args, **kwargs)
File "/home/tertia/workspace/odoo8/custom_modules/g4e_config/lager.py", line 225, in write
self.flaeche = 37
File "/home/tertia/workspace/odoo8/openerp/fields.py", line 853, in __set__
record.write({self.name: self.convert_to_write(value)})
File "/home/tertia/workspace/odoo8/openerp/api.py", line 239, in wrapper
return new_api(self, *args, **kwargs)
File "/home/tertia/workspace/odoo8/custom_modules/g4e_config/lager.py", line 225, in write
self.flaeche = 37
File "/home/tertia/workspace/odoo8/openerp/fields.py", line 853, in __set__
record.write({self.name: self.convert_to_write(value)})
File "/home/tertia/workspace/odoo8/openerp/api.py", line 239, in wrapper
return new_api(self, *args, **kwargs)

.....

File "/home/tertia/workspace/odoo8/custom_modules/g4e_config/lager.py", line 225, in write
self.flaeche = 37
File "/home/tertia/workspace/odoo8/openerp/fields.py", line 853, in __set__
record.write({self.name: self.convert_to_write(value)})
File "/home/tertia/workspace/odoo8/openerp/api.py", line 239, in wrapper
return new_api(self, *args, **kwargs)
File "/home/tertia/workspace/odoo8/custom_modules/g4e_config/lager.py", line 225, in write
self.flaeche = 37
File "/home/tertia/workspace/odoo8/openerp/fields.py", line 853, in __set__
record.write({self.name: self.convert_to_write(value)})
File "/home/tertia/workspace/odoo8/openerp/api.py", line 239, in wrapper
return new_api(self, *args, **kwargs)
File "/home/tertia/workspace/odoo8/custom_modules/g4e_config/lager.py", line 224, in write
super(lager, self).write(vals)
File "/home/tertia/workspace/odoo8/openerp/api.py", line 239, in wrapper
return new_api(self, *args, **kwargs)
File "/home/tertia/workspace/odoo8/openerp/api.py", line 546, in new_api
result = method(self._model, cr, uid, self.ids, *args, **kwargs)
File "/home/tertia/workspace/odoo8/openerp/addons/mail/mail_thread.py", line 435, in write
self.message_auto_subscribe(cr, uid, ids, values.keys(), context=context, values=values)
File "/home/tertia/workspace/odoo8/openerp/api.py", line 241, in wrapper
return old_api(self, *args, **kwargs)
File "/home/tertia/workspace/odoo8/openerp/addons/mail/mail_thread.py", line 1883, in message_auto_subscribe
header_subtype_ids = subtype_obj.search(cr, uid, ['|', ('res_model', '=', False), ('parent_id.res_model', '=', self._name)], context=context)
File "/home/tertia/workspace/odoo8/openerp/api.py", line 241, in wrapper
return old_api(self, *args, **kwargs)
File "/home/tertia/workspace/odoo8/openerp/models.py", line 1639, in search
return self._search(cr, user, args, offset=offset, limit=limit, order=order, context=context, count=count)
File "/home/tertia/workspace/odoo8/openerp/api.py", line 241, in wrapper
return old_api(self, *args, **kwargs)
File "/home/tertia/workspace/odoo8/openerp/models.py", line 4621, in _search
query = self._where_calc(cr, user, args, context=context)
File "/home/tertia/workspace/odoo8/openerp/api.py", line 241, in wrapper
return old_api(self, *args, **kwargs)
File "/home/tertia/workspace/odoo8/openerp/models.py", line 4444, in _where_calc
e = expression.expression(cr, user, domain, self, context)
File "/home/tertia/workspace/odoo8/openerp/osv/expression.py", line 646, in __init__
self.parse(cr, uid, context=context)
File "/home/tertia/workspace/odoo8/openerp/osv/expression.py", line 847, in parse
right_ids = comodel.search(cr, uid, [(path[1], operator, right)], context=context)
File "/home/tertia/workspace/odoo8/openerp/api.py", line 241, in wrapper
return old_api(self, *args, **kwargs)
File "/home/tertia/workspace/odoo8/openerp/models.py", line 1639, in search
return self._search(cr, user, args, offset=offset, limit=limit, order=order, context=context, count=count)
File "/home/tertia/workspace/odoo8/openerp/api.py", line 241, in wrapper
return old_api(self, *args, **kwargs)
File "/home/tertia/workspace/odoo8/openerp/models.py", line 4615, in _search
self.check_access_rights(cr, access_rights_uid or user, 'read')
File "/home/tertia/workspace/odoo8/openerp/api.py", line 241, in wrapper
return old_api(self, *args, **kwargs)
File "/home/tertia/workspace/odoo8/openerp/models.py", line 3477, in check_access_rights
return self.pool.get('ir.model.access').check(cr, uid, self._name, operation, raise_exception)
File "/home/tertia/workspace/odoo8/openerp/api.py", line 241, in wrapper
return old_api(self, *args, **kwargs)
File "<string>", line 2, in check
File "/home/tertia/workspace/odoo8/openerp/tools/cache.py", line 117, in lookup
r = d[key]
File "/home/tertia/workspace/odoo8/openerp/tools/func.py", line 66, in wrapper
return func(self, *args, **kwargs)
File "/home/tertia/workspace/odoo8/openerp/tools/lru.py", line 38, in __getitem__
self[a[0]] = a[1]
File "/home/tertia/workspace/odoo8/openerp/tools/func.py", line 66, in wrapper
return func(self, *args, **kwargs)
File "/home/tertia/workspace/odoo8/openerp/tools/lru.py", line 44, in __setitem__
del self[obj]


The same happens when I want to call a function of the
lager
model.
What am I doing wrong?

Answer

The problem is that by writing self.flaeche = 37 you are changing the record, which means implicitly calling the write() method on the model. When you call write() from write() you obviously end up with recursion.

You can do something similar to this instead:

@api.multi
def write(self, vals):
    vals['flaeche'] = 37
    return super(lager, self).write(vals)

This way there are no additional writes - you just change the values for a write that was about to happen anyway.

If you want to allow people to explicitly overwrite the value of 37 you can do this:

@api.multi
def write(self, vals):
    if 'flaeche' not in vals:
        vals['flaeche'] = 37
    return super(lager, self).write(vals)