odoo-survey-addons/survey_input_attachment/models/survey_question.py

# -*- coding: utf-8 -*-
from odoo import models, fields, api, _
from werkzeug.datastructures import FileStorage

TYPES = [
    ('free_text', _('Multiple Lines Text Box')),
    ('textbox', _('Single Line Text Box')),
    ('numerical_box', _('Numerical Value')),
    ('date', _('Date')),
    ('upload_file', _('Attachment')),
    ('simple_choice', _('Multiple choice: only one answer')),
    ('multiple_choice', _('Multiple choice: multiple answers allowed')),
    ('matrix', _('Matrix')),
]


class SurveyQuestion(models.Model):
    _inherit = 'survey.question'

    # question_attachment = fields.Binary(string="Joined attachment")
    type = fields.Selection(selection=TYPES)

    @api.multi
    def validate_upload_file(self, post, answer_tag):
        self.ensure_one()
        errors = {}
        # Empty answer to mandatory question
        if self.constr_mandatory and not isinstance(post[answer_tag], FileStorage):
            errors.update({answer_tag: self.constr_error_msg})
        # Bad file type
        if isinstance(post[answer_tag], FileStorage) and post[answer_tag].content_type != 'application/pdf' and 'image/' not in post[answer_tag].content_type:
            errors.update({answer_tag: _("The file you joined is not an image nor a PDF file.")})
        return errors