moviewyrm/bookwyrm/models/book.py
2021-09-22 16:08:25 -07:00

389 lines
13 KiB
Python

""" database schema for books and shelves """
import re
from django.contrib.postgres.search import SearchVectorField
from django.contrib.postgres.indexes import GinIndex
from django.db import models, transaction
from django.db.models import Prefetch
from django.dispatch import receiver
from model_utils import FieldTracker
from model_utils.managers import InheritanceManager
from imagekit.models import ImageSpecField
from bookwyrm import activitypub
from bookwyrm.preview_images import generate_edition_preview_image_task
from bookwyrm.settings import (
DOMAIN,
DEFAULT_LANGUAGE,
ENABLE_PREVIEW_IMAGES,
ENABLE_THUMBNAIL_GENERATION,
)
from .activitypub_mixin import OrderedCollectionPageMixin, ObjectMixin
from .base_model import BookWyrmModel
from . import fields
class BookDataModel(ObjectMixin, BookWyrmModel):
"""fields shared between editable book data (books, works, authors)"""
origin_id = models.CharField(max_length=255, null=True, blank=True)
openlibrary_key = fields.CharField(
max_length=255, blank=True, null=True, deduplication_field=True
)
inventaire_id = fields.CharField(
max_length=255, blank=True, null=True, deduplication_field=True
)
librarything_key = fields.CharField(
max_length=255, blank=True, null=True, deduplication_field=True
)
goodreads_key = fields.CharField(
max_length=255, blank=True, null=True, deduplication_field=True
)
bnf_id = fields.CharField( # Bibliothèque nationale de France
max_length=255, blank=True, null=True, deduplication_field=True
)
search_vector = SearchVectorField(null=True)
last_edited_by = fields.ForeignKey(
"User",
on_delete=models.PROTECT,
null=True,
)
class Meta:
"""can't initialize this model, that wouldn't make sense"""
abstract = True
def save(self, *args, **kwargs):
"""ensure that the remote_id is within this instance"""
if self.id:
self.remote_id = self.get_remote_id()
else:
self.origin_id = self.remote_id
self.remote_id = None
return super().save(*args, **kwargs)
def broadcast(self, activity, sender, software="bookwyrm"):
"""only send book data updates to other bookwyrm instances"""
super().broadcast(activity, sender, software=software)
class Book(BookDataModel):
"""a generic book, which can mean either an edition or a work"""
connector = models.ForeignKey("Connector", on_delete=models.PROTECT, null=True)
# book/work metadata
title = fields.TextField(max_length=255)
sort_title = fields.CharField(max_length=255, blank=True, null=True)
subtitle = fields.TextField(max_length=255, blank=True, null=True)
description = fields.HtmlField(blank=True, null=True)
languages = fields.ArrayField(
models.CharField(max_length=255), blank=True, default=list
)
series = fields.TextField(max_length=255, blank=True, null=True)
series_number = fields.CharField(max_length=255, blank=True, null=True)
subjects = fields.ArrayField(
models.CharField(max_length=255), blank=True, null=True, default=list
)
subject_places = fields.ArrayField(
models.CharField(max_length=255), blank=True, null=True, default=list
)
authors = fields.ManyToManyField("Author")
cover = fields.ImageField(
upload_to="covers/", blank=True, null=True, alt_field="alt_text"
)
preview_image = models.ImageField(
upload_to="previews/covers/", blank=True, null=True
)
first_published_date = fields.DateTimeField(blank=True, null=True)
published_date = fields.DateTimeField(blank=True, null=True)
objects = InheritanceManager()
field_tracker = FieldTracker(fields=["authors", "title", "subtitle", "cover"])
if ENABLE_THUMBNAIL_GENERATION:
cover_bw_book_xsmall_webp = ImageSpecField(
source="cover", id="bw:book:xsmall:webp"
)
cover_bw_book_xsmall_jpg = ImageSpecField(
source="cover", id="bw:book:xsmall:jpg"
)
cover_bw_book_small_webp = ImageSpecField(
source="cover", id="bw:book:small:webp"
)
cover_bw_book_small_jpg = ImageSpecField(source="cover", id="bw:book:small:jpg")
cover_bw_book_medium_webp = ImageSpecField(
source="cover", id="bw:book:medium:webp"
)
cover_bw_book_medium_jpg = ImageSpecField(
source="cover", id="bw:book:medium:jpg"
)
cover_bw_book_large_webp = ImageSpecField(
source="cover", id="bw:book:large:webp"
)
cover_bw_book_large_jpg = ImageSpecField(source="cover", id="bw:book:large:jpg")
cover_bw_book_xlarge_webp = ImageSpecField(
source="cover", id="bw:book:xlarge:webp"
)
cover_bw_book_xlarge_jpg = ImageSpecField(
source="cover", id="bw:book:xlarge:jpg"
)
cover_bw_book_xxlarge_webp = ImageSpecField(
source="cover", id="bw:book:xxlarge:webp"
)
cover_bw_book_xxlarge_jpg = ImageSpecField(
source="cover", id="bw:book:xxlarge:jpg"
)
@property
def author_text(self):
"""format a list of authors"""
return ", ".join(a.name for a in self.authors.all())
@property
def latest_readthrough(self):
"""most recent readthrough activity"""
return self.readthrough_set.order_by("-updated_date").first()
@property
def edition_info(self):
"""properties of this edition, as a string"""
items = [
self.physical_format if hasattr(self, "physical_format") else None,
self.languages[0] + " language"
if self.languages and self.languages[0] != "English"
else None,
str(self.published_date.year) if self.published_date else None,
", ".join(self.publishers) if hasattr(self, "publishers") else None,
]
return ", ".join(i for i in items if i)
@property
def alt_text(self):
"""image alt test"""
text = self.title
if self.edition_info:
text += f" ({self.edition_info})"
return text
def save(self, *args, **kwargs):
"""can't be abstract for query reasons, but you shouldn't USE it"""
if not isinstance(self, Edition) and not isinstance(self, Work):
raise ValueError("Books should be added as Editions or Works")
return super().save(*args, **kwargs)
def get_remote_id(self):
"""editions and works both use "book" instead of model_name"""
return f"https://{DOMAIN}/book/{self.id}"
def __repr__(self):
# pylint: disable=consider-using-f-string
return "<{} key={!r} title={!r}>".format(
self.__class__,
self.openlibrary_key,
self.title,
)
class Meta:
"""sets up postgres GIN index field"""
indexes = (GinIndex(fields=["search_vector"]),)
class Work(OrderedCollectionPageMixin, Book):
"""a work (an abstract concept of a book that manifests in an edition)"""
# library of congress catalog control number
lccn = fields.CharField(
max_length=255, blank=True, null=True, deduplication_field=True
)
def save(self, *args, **kwargs):
"""set some fields on the edition object"""
# set rank
for edition in self.editions.all():
edition.save()
return super().save(*args, **kwargs)
@property
def default_edition(self):
"""in case the default edition is not set"""
return self.editions.order_by("-edition_rank").first()
def to_edition_list(self, **kwargs):
"""an ordered collection of editions"""
return self.to_ordered_collection(
self.editions.order_by("-edition_rank").all(),
remote_id=f"{self.remote_id}/editions",
**kwargs,
)
activity_serializer = activitypub.Work
serialize_reverse_fields = [("editions", "editions", "-edition_rank")]
deserialize_reverse_fields = [("editions", "editions")]
class Edition(Book):
"""an edition of a book"""
# these identifiers only apply to editions, not works
isbn_10 = fields.CharField(
max_length=255, blank=True, null=True, deduplication_field=True
)
isbn_13 = fields.CharField(
max_length=255, blank=True, null=True, deduplication_field=True
)
oclc_number = fields.CharField(
max_length=255, blank=True, null=True, deduplication_field=True
)
asin = fields.CharField(
max_length=255, blank=True, null=True, deduplication_field=True
)
pages = fields.IntegerField(blank=True, null=True)
physical_format = fields.CharField(max_length=255, blank=True, null=True)
publishers = fields.ArrayField(
models.CharField(max_length=255), blank=True, default=list
)
shelves = models.ManyToManyField(
"Shelf",
symmetrical=False,
through="ShelfBook",
through_fields=("book", "shelf"),
)
parent_work = fields.ForeignKey(
"Work",
on_delete=models.PROTECT,
null=True,
related_name="editions",
activitypub_field="work",
)
edition_rank = fields.IntegerField(default=0)
activity_serializer = activitypub.Edition
name_field = "title"
def get_rank(self):
"""calculate how complete the data is on this edition"""
rank = 0
# big ups for havinga cover
rank += int(bool(self.cover)) * 3
# is it in the instance's preferred language?
rank += int(bool(DEFAULT_LANGUAGE in self.languages))
# prefer print editions
if self.physical_format:
rank += int(
bool(self.physical_format.lower() in ["paperback", "hardcover"])
)
# does it have metadata?
rank += int(bool(self.isbn_13))
rank += int(bool(self.isbn_10))
rank += int(bool(self.oclc_number))
rank += int(bool(self.pages))
rank += int(bool(self.physical_format))
rank += int(bool(self.description))
# max rank is 9
return rank
def save(self, *args, **kwargs):
"""set some fields on the edition object"""
# calculate isbn 10/13
if self.isbn_13 and self.isbn_13[:3] == "978" and not self.isbn_10:
self.isbn_10 = isbn_13_to_10(self.isbn_13)
if self.isbn_10 and not self.isbn_13:
self.isbn_13 = isbn_10_to_13(self.isbn_10)
# normalize isbn format
if self.isbn_10:
self.isbn_10 = re.sub(r"[^0-9X]", "", self.isbn_10)
if self.isbn_13:
self.isbn_13 = re.sub(r"[^0-9X]", "", self.isbn_13)
# set rank
self.edition_rank = self.get_rank()
return super().save(*args, **kwargs)
@classmethod
def viewer_aware_objects(cls, viewer):
"""annotate a book query with metadata related to the user"""
queryset = cls.objects
if not viewer or not viewer.is_authenticated:
return queryset
queryset = queryset.prefetch_related(
Prefetch(
"shelfbook_set",
queryset=viewer.shelfbook_set.all(),
to_attr="current_shelves",
),
Prefetch(
"readthrough_set",
queryset=viewer.readthrough_set.filter(is_active=True).all(),
to_attr="active_readthroughs",
),
)
return queryset
def isbn_10_to_13(isbn_10):
"""convert an isbn 10 into an isbn 13"""
isbn_10 = re.sub(r"[^0-9X]", "", isbn_10)
# drop the last character of the isbn 10 number (the original checkdigit)
converted = isbn_10[:9]
# add "978" to the front
converted = "978" + converted
# add a check digit to the end
# multiply the odd digits by 1 and the even digits by 3 and sum them
try:
checksum = sum(int(i) for i in converted[::2]) + sum(
int(i) * 3 for i in converted[1::2]
)
except ValueError:
return None
# add the checksum mod 10 to the end
checkdigit = checksum % 10
if checkdigit != 0:
checkdigit = 10 - checkdigit
return converted + str(checkdigit)
def isbn_13_to_10(isbn_13):
"""convert isbn 13 to 10, if possible"""
if isbn_13[:3] != "978":
return None
isbn_13 = re.sub(r"[^0-9X]", "", isbn_13)
# remove '978' and old checkdigit
converted = isbn_13[3:-1]
# calculate checkdigit
# multiple each digit by 10,9,8.. successively and sum them
try:
checksum = sum(int(d) * (10 - idx) for (idx, d) in enumerate(converted))
except ValueError:
return None
checkdigit = checksum % 11
checkdigit = 11 - checkdigit
if checkdigit == 10:
checkdigit = "X"
return converted + str(checkdigit)
# pylint: disable=unused-argument
@receiver(models.signals.post_save, sender=Edition)
def preview_image(instance, *args, **kwargs):
"""create preview image on book create"""
if not ENABLE_PREVIEW_IMAGES:
return
changed_fields = {}
if instance.field_tracker:
changed_fields = instance.field_tracker.changed()
if len(changed_fields) > 0:
transaction.on_commit(
lambda: generate_edition_preview_image_task.delay(instance.id)
)