how to modify fields of hr.attendance via a modification request automatically - python-3.x

Question

i'm using odoo 11. i have create a custom module for attendance modification request which be approuved by the manager of attendance . My goal is to limit the acces to the modification of attendance and when the manager press approuve "hr.attendance" will be modified automatically whith the new values of check_in and check_out (if it's the same employee and same date between "hr.attendance" and my request modification). The problem is when i press approuve there is no error but in the same time there is no modification.
Here is my code. Any idea for help please ?
modification_request.xml
<record model="ir.ui.view" id="view_attendance_modification_request_form">
<field name="name">attendance.modification.request.form</field>
<field name="model">attendance.modification.request</field>
<field name="arch" type="xml">
<form string="Attendance modification Request">
<header>
<field name="state" statusbar_visible="draft,waiting,approved,cancel" widget="statusbar" />
<button name="submit_modification" string="Submit for manager" type="object" class="btn-primary"
attrs="{'invisible': [('state','not in','draft')]}"/>
<button name="modification_approval" type="object" string="Approve" class="oe_highlight"
groups="hr_attendance.group_hr_attendance_manager"
attrs="{'invisible': [('state','not in','waiting')]}"/>
<button name="modification_rejection" type="object" string="Cancel" class="oe_highlight"
groups="hr_attendance.group_hr_attendance_manager"
attrs="{'invisible': [('state','not in','waiting')]}"/>
</header>
<sheet>
<h2>
<group>
<field name="employee_id"/>
</group>
</h2>
<group col="4" colspan="4">
<field name="time_check_in_1"/>
<field name="time_check_out_1"/>
</group>
<label for="note"/>
<field name="note"/>
</sheet>
<field name="message_follower_ids" widget="mail_followers" groups="base.group_user"/>
<field name="activity_ids" widget="mail_activity"/>
<field name="message_ids" widget="mail_thread"/>
</form>
</field>
</record>
modification_request.py
class AttendanceModificationRequest(models.Model):
_name = 'attendance.modification.request'
_description = 'Attendance modification Request'
_inherit = ['mail.thread', 'mail.activity.mixin']
def _get_employee_id(self):
employee_rec = self.env['hr.employee'].search([('user_id', '=', self.env.uid)], limit=1)
return employee_rec.id
employee_id = fields.Many2one('hr.employee',"Employee", readonly=True,default=_get_employee_id, required=True)
user_id = fields.Many2one('res.users', string='User', track_visibility='onchange', readonly=True,
states={'draft': [('readonly', False)]}, default=lambda self: self.env.user)
state = fields.Selection([
('draft', 'Pending'),
('waiting', 'Waiting for approval'),
('approved', 'Approved'),
('cancel', 'Cancelled')], readonly=True,
help="Gives the state of the attendance request modification .",
default='draft')
modification_date = fields.Date("Date")
time_check_in_1 = fields.Datetime("Check in")
time_check_out_1 = fields.Datetime("Check out")
note = fields.Text("Note")
attendance_id = fields.Many2one('hr.attendance', string='Attendance')
#api.multi
def modification_approval(self):
attend_signin_ids = self.env['hr.attendance']
check_in_date = datetime.strptime(self.time_check_in_1, "%Y-%m-%d %H:%M:%S").date()
check_out_date = datetime.strptime(self.time_check_out_1, "%Y-%m-%d %H:%M:%S").date()
for record in self:
attendance_check_in_date = datetime.strptime(record.attendance_id.check_in, "%Y-%m-%d %H:%M:%S").date()
attendance_check_out_date = datetime.strptime(record.attendance_id.check_out, "%Y-%m-%d %H:%M:%S").date()
if (record.attendance_id.employee_id == self.employee_id) and (check_in_date == attendance_check_in_date):
record.attendance_id.check_in = self.time_check_in_1
record.attendance_id.check_out = self.time_check_out_1
return self.write({
'state': 'approved'
})

Answer 1

since attendance_ids is a group of people. attendance_id = fields.Many2one('hr.attendance', string='Attendance') is an issue.
Because m2o can't refer to a group of people.
attendance_id = fields.One2many('hr.attendance','keyfield_in_hr_attendance' ,string='Attendance') is correct.
And keyfield_in_hr_attendance is a many2one field refer to attendance.modification.request model.