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Calculating the difference between two dates

on 7/3/15, 6:08 AM 1,246 views


This is my first post here. I'm newbie with Odoo, but I'm trying to learn more about it.

I'm writing my first module. I put this piece of code into my class:

        def _get_days(self,cr,uid,ids,field_name, arg ,context=None):
res = {},
fmt = '%d-%m-%Y',
for obj in self.browse(cr, uid, ids, context=context):
#res[obj.id] = {'diff_days':0, }, #valore di default
from_date = obj.data_inizio,
to_date = obj.data_fine,
d1 = datetime.strptime(from_date, fmt),
d2 = datetime.strptime(to_date, fmt),
daysDiff = str((d2-d1).days),
res[obj.id]['diff_days'] = daysDiff,
return res

I've declared 'data_inizio', 'data_fine' and 'diff_days' in this way:

        _columns = {

'data_inizio': fields.date('Data Inizio', required=True),
            'data_fine': fields.date('Data Fine', required=True),
            'diff_days': fields.function(_get_days, string='Diff days', multi='sums', store=True),


I've followed the instructions of this post: https://www.odoo.com/fr_FR/forum/help-1/question/how-to-calculate-difference-bitween-two-dates-31486

When I try to create a new input, I get this error:


Odoo Server Error

Traceback (most recent call last):
File "/home/Odoo/openerp/openerp/http.py", line 530, in _handle_exception
return super(JsonRequest, self)._handle_exception(exception)
File "/home/Odoo/openerp/openerp/http.py", line 567, in dispatch
result = self._call_function(**self.params)
File "/home/Odoo/openerp/openerp/http.py", line 303, in _call_function
return checked_call(self.db, *args, **kwargs)
File "/home/Odoo/openerp/openerp/service/model.py", line 113, in wrapper
return f(dbname, *args, **kwargs)
File "/home/Odoo/openerp/openerp/http.py", line 300, in checked_call
return self.endpoint(*a, **kw)
File "/home/Odoo/openerp/openerp/http.py", line 796, in __call__
return self.method(*args, **kw)
File "/home/Odoo/openerp/openerp/http.py", line 396, in response_wrap
response = f(*args, **kw)
File "/home/Odoo/openerp/openerp/addons/web/controllers/main.py", line 949, in call_kw
return self._call_kw(model, method, args, kwargs)
File "/home/Odoo/openerp/openerp/addons/web/controllers/main.py", line 941, in _call_kw
return getattr(request.registry.get(model), method)(request.cr, request.uid, *args, **kwargs)
File "/home/Odoo/openerp/openerp/api.py", line 241, in wrapper
return old_api(self, *args, **kwargs)
File "/home/Odoo/openerp/openerp/api.py", line 336, in old_api
result = method(recs, *args, **kwargs)
File "/home/Odoo/openerp/openerp/models.py", line 4025, in create
record = self.browse(self._create(old_vals))
File "/home/Odoo/openerp/openerp/api.py", line 239, in wrapper
return new_api(self, *args, **kwargs)
File "/home/Odoo/openerp/openerp/api.py", line 462, in new_api
result = method(self._model, cr, uid, *args, **kwargs)
File "/home/Odoo/openerp/openerp/models.py", line 4226, in _create
self.pool[model_name]._store_set_values(cr, user, ids, fields2, context)
File "/home/Odoo/openerp/openerp/api.py", line 241, in wrapper
return old_api(self, *args, **kwargs)
File "/home/Odoo/openerp/openerp/models.py", line 4335, in _store_set_values
result = self._columns[val[0]].get(cr, self, ids, val, SUPERUSER_ID, context=context)
File "/home/Odoo/openerp/openerp/osv/fields.py", line 1361, in get
result = self._fnct(obj, cr, uid, ids, name, self._arg, context)
File "/home/Odoo/openerp/openerp/addons/mymodule/mymodule.py", line 28, in _get_days
d1 = datetime.strptime(from_date, fmt),
TypeError: must be string, not tuple

Could anyone hel me?

Thanks in advance.

Uilino, Strange error! The date will always be the type string. Would you please debug and try to print the type(from_date) before the errorneous statement? Thanks.

Serpent Consulting Services Pvt. Ltd.
on 7/3/15, 6:43 AM

Emipro Technologies Pvt. Ltd.

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On 7/3/15, 7:39 AM


Please make your code as like below. It will resolve your entire problem.

def _get_days(self,cr,uid,ids,field_name, arg ,context=None):

res = {}

fmt = '%d-%m-%Y'

for obj in self.browse(cr, uid, ids, context=context):

#res[obj.id] = {'diff_days':0, }, #valore di default

from_date = obj.data_inizio

to_date = obj.data_fine

d1 = datetime.strptime(from_date, fmt)

d2 = datetime.strptime(to_date, fmt)

daysDiff = str((d2-d1).days)

res[obj.id]['diff_days'] = daysDiff

return res

I have just removed "," from end of every line.

When you have given from_date = obj.data_inizio,  at that time python assign tuple inside "from_date" variable. That's why you got an error that :

File "/home/Odoo/openerp/openerp/addons/mymodule/mymodule.py", line 28, in _get_days

d1 = datetime.strptime(from_date, fmt),

TypeError: must be string, not tuple

I am "sure" your issue will resolve.

On 7/3/15, 9:02 AM

It works!

Thank you very much.

I also have uncommented this line:

#res[obj.id] = {'diff_days':0, }, 

without ",".

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Asked: 7/3/15, 6:08 AM
Seen: 1246 times
Last updated: 7/3/15, 9:02 AM