library/library_app/models/library_book.py

from odoo import api, fields, models
from odoo.exceptions import Warning
from odoo.exceptions import ValidationError

class Book(models.Model):
    _name = 'library.book'
    _description = 'Book'
    _order = 'name, date_published desc' 

    # 字符字段
    name = fields.Char('Title', required=True)
    isbn = fields.Char('ISBN')
    book_type = fields.Selection(
        [('paper', 'Paperback'),
        ('hard', 'Hardcover'),
        ('electronic', 'Electronic'),
        ('other', 'Other')],
        'Type')
    notes = fields.Text('Internal Notes')
    descr = fields.Html('Description')
 
    # 数字字段
    copies = fields.Integer(default=1)
    avg_rating = fields.Float('Average Rating', (3,2))
    price = fields.Monetary('Price', 'currency_id')
    currency_id = fields.Many2one('res.currency') # price helper
 
    # 日期、时间字段
    date_published = fields.Date()
    last_borrow_date = fields.Datetime(
        'Last Borrowed On',
        default=lambda self: fields.Datetime.now())
 
    # 其他字段
    active = fields.Boolean('Active?', default=True)
    image = fields.Binary('Cover')
 
    # 关系字段
    author_ids = fields.Many2many(
        'res.partner', string='Authors')
    publisher_id = fields.Many2one(
        'res.partner', string='Publisher')

    # 计算字段
    publisher_country_id = fields.Many2one(
        'res.country', string='Publisher Country',
        compute='_compute_publisher_country',
        # store = False, # 默认不在数据库中存储
        inverse='_inverse_publisher_country',
        search='_search_publisher_country',
    )
 
    @api.depends('publisher_id.country_id')
    def _compute_publisher_country(self):
        for book in self:
            book.publisher_country_id = book.publisher_id.country_id

    # 计算字段执行写入
    def _inverse_publisher_country(self):
        for book in self:
            book.publisher_id.country_id = book.publisher_country_id

    # 计算字段搜索 域表达式使用publisher_id.country_id字段
    def _search_publisher_country(self, operator, value):
        return [('publisher_id.country_id', operator, value)]

    # python 模型约束
    @api.constrains('isbn')
    def _constrain_isbn_valid(self):
        for book in self:
            if book.isbn and not book._check_isbn():
                raise ValidationError('%s is an invalid ISBN' % book.isbn)

    def _check_isbn(self):
        self.ensure_one() 
        isbn = self.isbn.replace('-', '') # 为保持兼容性 Alan 自行添加
        digits = [int(x) for x in isbn if x.isdigit()]
        if len(digits) == 13:
            ponderations = [1, 3] * 6
            terms = [a * b for a,b in zip(digits[:13], ponderations)]
            remain = sum(terms) % 10
            check = 10 - remain if remain !=0 else 0
            return digits[-1] == check

    def button_check_isbn(self):
        for book in self:
            if not book.isbn:
                raise Warning('Please provide an ISBN for %s' % book.name)
            if book.isbn and not book._check_isbn():
                raise Warning('%s is an invalid ISBN' % book.isbn)
        return True

    # 数据库约束
    _sql_constraints = [
        ('library_book_name_date_uq', # 约束唯一标识符
        'UNIQUE (name, date_published)', # 约束 SQL 语法
        'Book title and publication date must be unique'), # 消息
        ('library_book_check_date',
        'CHECK (date_published <= current_date)',
        'Publication date must not be in the future.'),
    ]