Why my One2Many field does not save more than one record?

Question

I have two models. One model has an One2Many field pointing to the other one. When I save the main record, it only saves one record of the One2many relation. I need it to save 'n' records. Maybe the problem is the structure of the data I planned.

Here is the code. I'm sorry for the Spanish names of the variables.

Thanks in advance.

This is the first class it calls the second class with One2Many relation.

class EmpleadosProductos(models.Model): _name = "employee.as.product"

    #the One2Many relation of the trouble
    employee_line = fields.One2many(
        'employee.line', 
        'id', 
        string='Employee Lines',
        store=True
        )

    companyias = fields.Many2one('res.partner', 'Compañia', domain=[('is_company', '=', True)])
    amount_total = fields.Monetary(string='Total', store=True, readonly=True, compute='_calcularTotal')
    journal_entry = fields.Many2one('account.move')
    currency_id = fields.Many2one('res.currency', 'Currency', required=True, default=lambda self: self.env.user.company_id.currency_id.id)
    fecha = fields.Date('Fecha')
    referencia = fields.Char(string='Ref', required=True) 
    _sql_constraints = [
        ('refererecia_constraint', 'unique(referencia)', 'La referencia debe de ser única!'),
    ]
    @api.one
    @api.depends('employee_line.total')
        def _calcularTotal(self):
            for empleado_obra in self:
                acumulador = 0.0
                for linea in empleado_obra.employee_line:
                    acumulador += linea.total
                empleado_obra.update({
                    'amount_total': acumulador
                })

This is the second class called in the One2Many relation.

class EmployeLine(models.Model):
    _name = 'employee.line'
    descripcion = fields.Text(string='Descripción', required=False)
    employee_id = fields.Many2one(
        'hr.employee', 
        string="Empleado",
        requiered=True,
        change_default=True
        )

    currency_id = fields.Many2one('res.currency', 'Currency', required=True, default=lambda self: self.env.user.company_id.currency_id.id)
    apodo = fields.Char('apodo', readonly=False)
    precio_por_hora = fields.Float('Sueldo/hora', store=True)
    numero_de_horas =  fields.Integer('Número de horas', store=True)

    total = fields.Monetary(string='Total', store=True, readonly=True, compute='_calcularTotalLine')
    _rec_name = 'apodo'

    @api.one
    @api.depends('numero_de_horas', 'precio_por_hora')
        def _calcularTotalLine(self):
             self.update({
                    'total': (self.precio_por_hora * self.numero_de_horas)
                })

    @api.onchange('employee_id')
        def onchange_employee_id(self):
            addr = {}
            if not self.employee_id.display_name:
                return addr
            if not self.employee_id.apodo:
                self.apodo = "no apodo"
            else:
                self.apodo = self.employee_id.apodo
                self.precio_por_hora = self.employee_id.precio_por_hora
            return addr

Answer 1

This is your One2many (I'm adding param names to explain the situation clearer):

# The One2Many relation of the trouble
employee_line = fields.One2many(
    comodel_name='employee.line', 
    inverse_name='id', 
    string='Employee Lines',
    store=True,
)

With that code you are telling Odoo that there is a Many2one field named id in employee.line model which points to employee.as.product model. Of course, there is an id field in employee.line model, but it is not an ID of employee.as.product at all. It is the key of each record, created by default in every model (in this case employee.line), so you cannot set it as the inverse_name of the One2many.

What you want is this:

Create a Many2one field in employee.line model:

employee_as_product_id = fields.Many2one(
    comodel_name='employee.as.product',
    string='Empleado/Producto',
)

Correct your One2many field in employee.as.product model this way:

employee_line = fields.One2many(
    comodel_name='employee.line', 
    inverse_name='employee_as_product_id', 
    string='Employee Lines',
    store=True,
)

And the One2many field will work as expected.