Why do I get this error?: Expected singleton: spray.action(1, 2) - odoo-10

Question

I have a button in a form that when clicked is supposed to update the current model mrl with data from the spray.action model. Then I do further processing but it raises the error
ValueError("Expected singleton: %s" % self) ValueError: Expected singleton: spray.action(1, 2)
#api.multi
def mrlCreateSprayRecords(self):
spray_ids = []
vals = []
spray_obj = self.env['spray.action'].search([])
print("spray_obj \n\n\n\t %s ", spray_obj)
for obj in spray_obj:
print("Spray Action Objects \n\n %s \n\t ", obj)
vals = {
'ref': obj.ref,
'farm': obj.farm.farm,
'block': obj.block.block,
'valves': obj.valves.valve,
}
print("Spray Action Data Browse , \n\n\t %s ", vals)
res = super(Mrl, self).create(vals)
res.update(vals)
print("object in mrlCreateSprayRecords \n\n\t %s", res)
return {
'name': 'Update Mrl Operations',
'type': 'ir.actions.act_window',
'view_type': 'form',
'view_mode': 'form',
'res_model': 'mrl',
'views': [(spray_obj.id, 'form')],
'view_id': spray_obj.id,
# 'target': 'new',
'res_id': self.id,
'context': self.env.context,
}

Answer 1

I think you are getting the error in the row 'view_id': spray_obj.id, you must write the view id there. The spray_obj recordset has many record, so you cannot use it like that (spray_obj.id). You can also remove the view_id parameter in order to user the default view.
#api.multi
def mrlCreateSprayRecords(self):
self.ensure_one()
spray_obj = self.env['spray.action'].search([]) # recordset of all records of the model????
for obj in spray_obj:
vals = {
'ref': obj.ref,
'farm': obj.farm.farm,
'block': obj.block.block,
'valves': obj.valves.valve,
}
self.create(vals)
view_id = self.env.ref('module.xml_view_id').id
return {
'name': 'Update Mrl Operations',
'type': 'ir.actions.act_window',
'view_type': 'form',
'view_mode': 'form',
'res_model': 'mrl',
'view_id': view_id,
'res_id': self.id,
'context': self.env.context,
}
I have added self.ensure_one() because res_id has to be only one id as well.
I have remove the res.update(vals) line because it does not make any sense to me haha
More things
Instead of print you should use the logger:
import logging
_logger = logging.getLogger(__name__)
_logger.info('Hello')
Instead the line res = super(Mrl, self).create(vals) I think you should use this one
res = self.create(vals) # if you are in the mrl model

Answer 2

In short you get this kind of error when you acces a field direclty of a recordSet that contains more than one record.
You performed a search on the spray.action that search returnd 2 record (1, 2)
So when you do spray_obj.id odoo will be confused what id he should return 1 or 2. And here odoo throw this error.
So dont access a field a search result, or a x2many fiels they may have more than one record inside.
#ChesuCR has improved your code and corrected it