bookwyrm/bookwyrm/book_search.py
Mouse Reeve eb61033626 Simplify identifier searches
This commit removes code that deduplicated search results for identifier
searches. If it was the case that multiple books have the same
identifier, in theory this would produce better search results, but in
practice this doesn't happen very much, is probably worth seeing when
it does, and worsens the performance of identifier search overall.
2022-11-15 19:42:40 -08:00

143 lines
4.6 KiB
Python

""" using a bookwyrm instance as a source of book data """
from dataclasses import asdict, dataclass
from functools import reduce
import operator
from django.contrib.postgres.search import SearchRank, SearchQuery
from django.db.models import F, Q
from bookwyrm import models
from bookwyrm import connectors
from bookwyrm.settings import MEDIA_FULL_URL
# pylint: disable=arguments-differ
def search(query, min_confidence=0, filters=None, return_first=False):
"""search your local database"""
filters = filters or []
if not query:
return []
results = None
# first, try searching unqiue identifiers
# unique identifiers never have spaces, title/author usually do
if not " " in query:
results = search_identifiers(query, *filters, return_first=return_first)
# if there were no identifier results...
if not results:
# then try searching title/author
results = search_title_author(
query, min_confidence, *filters, return_first=return_first
)
return results
def isbn_search(query):
"""search your local database"""
if not query:
return []
# Up-case the ISBN string to ensure any 'X' check-digit is correct
# If the ISBN has only 9 characters, prepend missing zero
query = query.strip().upper().rjust(10, "0")
filters = [{f: query} for f in ["isbn_10", "isbn_13"]]
return models.Edition.objects.filter(
reduce(operator.or_, (Q(**f) for f in filters))
).distinct()
def format_search_result(search_result):
"""convert a book object into a search result object"""
cover = None
if search_result.cover:
cover = f"{MEDIA_FULL_URL}{search_result.cover}"
return SearchResult(
title=search_result.title,
key=search_result.remote_id,
author=search_result.author_text,
year=search_result.published_date.year
if search_result.published_date
else None,
cover=cover,
confidence=search_result.rank if hasattr(search_result, "rank") else 1,
connector="",
).json()
def search_identifiers(query, *filters, return_first=False):
"""tries remote_id, isbn; defined as dedupe fields on the model"""
if connectors.maybe_isbn(query):
# Oh did you think the 'S' in ISBN stood for 'standard'?
normalized_isbn = query.strip().upper().rjust(10, "0")
query = normalized_isbn
# pylint: disable=W0212
or_filters = [
{f.name: query}
for f in models.Edition._meta.get_fields()
if hasattr(f, "deduplication_field") and f.deduplication_field
]
results = models.Edition.objects.filter(
*filters, reduce(operator.or_, (Q(**f) for f in or_filters))
).distinct()
if return_first:
return results.first()
return results
def search_title_author(query, min_confidence, *filters, return_first=False):
"""searches for title and author"""
query = SearchQuery(query, config="simple") | SearchQuery(query, config="english")
results = (
models.Edition.objects.filter(*filters, search_vector=query)
.annotate(rank=SearchRank(F("search_vector"), query))
.filter(rank__gt=min_confidence)
.order_by("-rank")
)
# when there are multiple editions of the same work, pick the closest
editions_of_work = results.values("parent_work__id").values_list("parent_work__id")
# filter out multiple editions of the same work
list_results = []
for work_id in set(editions_of_work):
editions = results.filter(parent_work=work_id)
default = editions.order_by("-edition_rank").first()
default_rank = default.rank if default else 0
# if mutliple books have the top rank, pick the default edition
if default_rank == editions.first().rank:
result = default
else:
result = editions.first()
if return_first:
return result
list_results.append(result)
return list_results
@dataclass
class SearchResult:
"""standardized search result object"""
title: str
key: str
connector: object
view_link: str = None
author: str = None
year: str = None
cover: str = None
confidence: int = 1
def __repr__(self):
# pylint: disable=consider-using-f-string
return "<SearchResult key={!r} title={!r} author={!r} confidence={!r}>".format(
self.key, self.title, self.author, self.confidence
)
def json(self):
"""serialize a connector for json response"""
serialized = asdict(self)
del serialized["connector"]
return serialized