lib.itmens/books/models.py

import uuid
import django.contrib.postgres.fields as postgres
from django.utils.translation import ugettext_lazy as _
from django.db import models
from django.core.serializers.json import DjangoJSONEncoder
from django.shortcuts import reverse
from common.models import Entity, Mark, Review, Tag
from common.utils import GenerateDateUUIDMediaFilePath
from boofilsic.settings import BOOK_MEDIA_PATH_ROOT, DEFAULT_BOOK_IMAGE
from django.utils import timezone


def book_cover_path(instance, filename):
    return GenerateDateUUIDMediaFilePath(instance, filename, BOOK_MEDIA_PATH_ROOT)


class Book(Entity):
    # widely recognized name, usually in Chinese
    title = models.CharField(_("title"), max_length=200)
    subtitle = models.CharField(_("subtitle"), blank=True, default='', max_length=200)
    # original name, for books in foreign language
    orig_title = models.CharField(_("original title"), blank=True, default='', max_length=200)

    author = postgres.ArrayField(
        models.CharField(_("author"), blank=True, default='', max_length=100),
        null=True,
        blank=True,
        default=list,
    )
    translator = postgres.ArrayField(
        models.CharField(_("translator"), blank=True, default='', max_length=100),
        null=True,
        blank=True,
        default=list,
    )
    language = models.CharField(_("language"), blank=True, default='', max_length=10)
    pub_house = models.CharField(_("publishing house"), blank=True, default='', max_length=200)
    pub_year = models.IntegerField(_("published year"), null=True, blank=True)
    pub_month = models.IntegerField(_("published month"), null=True, blank=True)
    binding = models.CharField(_("binding"), blank=True, default='', max_length=50)
    # since data origin is not formatted and might be CNY USD or other currency, use char instead
    price = models.CharField(_("pricing"), blank=True, default='', max_length=50)
    pages = models.PositiveIntegerField(_("pages"), null=True, blank=True)
    isbn = models.CharField(_("ISBN"), blank=True, null=False, max_length=20, db_index=True, default='')
    # to store previously scrapped data 
    cover = models.ImageField(_("cover picture"), upload_to=book_cover_path, default=DEFAULT_BOOK_IMAGE, blank=True)
    contents = models.TextField(blank=True, default="")

    class Meta:
        # more info: https://docs.djangoproject.com/en/2.2/ref/models/options/
        # set managed=False if the model represents an existing table or
        # a database view that has been created by some other means.
        # check the link above for further info
        # managed = True
        # db_table = 'book'
        constraints = [
            models.CheckConstraint(check=models.Q(pub_year__gte=0), name='pub_year_lowerbound'),
            models.CheckConstraint(check=models.Q(pub_month__lte=12), name='pub_month_upperbound'),
            models.CheckConstraint(check=models.Q(pub_month__gte=1), name='pub_month_lowerbound'),
        ]

    def __str__(self):
        return self.title
    
    def get_absolute_url(self):
        return reverse("books:retrieve", args=[self.id])

    def get_tags_manager(self):
        return self.book_tags

    @property
    def verbose_category_name(self):
        return _("书籍")


class BookMark(Mark):
    book = models.ForeignKey(Book, on_delete=models.CASCADE, related_name='book_marks', null=True)
    class Meta:
        constraints = [
            models.UniqueConstraint(fields=['owner', 'book'], name="unique_book_mark")
        ]


class BookReview(Review):
    book = models.ForeignKey(Book, on_delete=models.CASCADE, related_name='book_reviews', null=True)
    class Meta:
        constraints = [
            models.UniqueConstraint(fields=['owner', 'book'], name="unique_book_review")
        ]    


class BookTag(Tag):
    book = models.ForeignKey(Book, on_delete=models.CASCADE, related_name='book_tags', null=True)
    mark = models.ForeignKey(BookMark, on_delete=models.CASCADE, related_name='bookmark_tags', null=True)
    class Meta:
        constraints = [
            models.UniqueConstraint(fields=['content', 'mark'], name="unique_bookmark_tag")
        ]