moviewyrm/bookwyrm/connectors/abstract_connector.py
2021-12-05 13:38:15 -08:00

336 lines
11 KiB
Python

""" functionality outline for a book data connector """
from abc import ABC, abstractmethod
import logging
from django.db import transaction
import requests
from requests.exceptions import RequestException
from bookwyrm import activitypub, models, settings
from .connector_manager import load_more_data, ConnectorException
from .format_mappings import format_mappings
logger = logging.getLogger(__name__)
class AbstractMinimalConnector(ABC):
"""just the bare bones, for other bookwyrm instances"""
def __init__(self, identifier):
# load connector settings
info = models.Connector.objects.get(identifier=identifier)
self.connector = info
# the things in the connector model to copy over
self_fields = [
"base_url",
"books_url",
"covers_url",
"search_url",
"isbn_search_url",
"name",
"identifier",
]
for field in self_fields:
setattr(self, field, getattr(info, field))
def search(self, query, min_confidence=None, timeout=5):
"""free text search"""
params = {}
if min_confidence:
params["min_confidence"] = min_confidence
data = self.get_search_data(
f"{self.search_url}{query}",
params=params,
timeout=timeout,
)
results = []
for doc in self.parse_search_data(data)[:10]:
results.append(self.format_search_result(doc))
return results
def isbn_search(self, query):
"""isbn search"""
params = {}
data = self.get_search_data(
f"{self.isbn_search_url}{query}",
params=params,
)
results = []
# this shouldn't be returning mutliple results, but just in case
for doc in self.parse_isbn_search_data(data)[:10]:
results.append(self.format_isbn_search_result(doc))
return results
def get_search_data(self, remote_id, **kwargs): # pylint: disable=no-self-use
"""this allows connectors to override the default behavior"""
return get_data(remote_id, **kwargs)
@abstractmethod
def get_or_create_book(self, remote_id):
"""pull up a book record by whatever means possible"""
@abstractmethod
def parse_search_data(self, data):
"""turn the result json from a search into a list"""
@abstractmethod
def format_search_result(self, search_result):
"""create a SearchResult obj from json"""
@abstractmethod
def parse_isbn_search_data(self, data):
"""turn the result json from a search into a list"""
@abstractmethod
def format_isbn_search_result(self, search_result):
"""create a SearchResult obj from json"""
class AbstractConnector(AbstractMinimalConnector):
"""generic book data connector"""
def __init__(self, identifier):
super().__init__(identifier)
# fields we want to look for in book data to copy over
# title we handle separately.
self.book_mappings = []
def get_or_create_book(self, remote_id):
"""translate arbitrary json into an Activitypub dataclass"""
# first, check if we have the origin_id saved
existing = models.Edition.find_existing_by_remote_id(
remote_id
) or models.Work.find_existing_by_remote_id(remote_id)
if existing:
if hasattr(existing, "default_edition"):
return existing.default_edition
return existing
# load the json data from the remote data source
data = self.get_book_data(remote_id)
if self.is_work_data(data):
try:
edition_data = self.get_edition_from_work_data(data)
except (KeyError, ConnectorException):
# hack: re-use the work data as the edition data
# this is why remote ids aren't necessarily unique
edition_data = data
work_data = data
else:
edition_data = data
try:
work_data = self.get_work_from_edition_data(data)
except (KeyError, ConnectorException) as err:
logger.exception(err)
work_data = data
if not work_data or not edition_data:
raise ConnectorException(f"Unable to load book data: {remote_id}")
with transaction.atomic():
# create activitypub object
work_activity = activitypub.Work(
**dict_from_mappings(work_data, self.book_mappings)
)
# this will dedupe automatically
work = work_activity.to_model(model=models.Work, overwrite=False)
for author in self.get_authors_from_data(work_data):
work.authors.add(author)
edition = self.create_edition_from_data(work, edition_data)
load_more_data.delay(self.connector.id, work.id)
return edition
def get_book_data(self, remote_id): # pylint: disable=no-self-use
"""this allows connectors to override the default behavior"""
return get_data(remote_id)
def create_edition_from_data(self, work, edition_data, instance=None):
"""if we already have the work, we're ready"""
mapped_data = dict_from_mappings(edition_data, self.book_mappings)
mapped_data["work"] = work.remote_id
edition_activity = activitypub.Edition(**mapped_data)
edition = edition_activity.to_model(
model=models.Edition, overwrite=False, instance=instance
)
# if we're updating an existing instance, we don't need to load authors
if instance:
return edition
if not edition.connector:
edition.connector = self.connector
edition.save(broadcast=False, update_fields=["connector"])
for author in self.get_authors_from_data(edition_data):
edition.authors.add(author)
# use the authors from the work if none are found for the edition
if not edition.authors.exists() and work.authors.exists():
edition.authors.set(work.authors.all())
return edition
def get_or_create_author(self, remote_id, instance=None):
"""load that author"""
if not instance:
existing = models.Author.find_existing_by_remote_id(remote_id)
if existing:
return existing
data = self.get_book_data(remote_id)
mapped_data = dict_from_mappings(data, self.author_mappings)
try:
activity = activitypub.Author(**mapped_data)
except activitypub.ActivitySerializerError:
return None
# this will dedupe
return activity.to_model(
model=models.Author, overwrite=False, instance=instance
)
def get_remote_id_from_model(self, obj):
"""given the data stored, how can we look this up"""
return getattr(obj, getattr(self, "generated_remote_link_field"))
def update_author_from_remote(self, obj):
"""load the remote data from this connector and add it to an existing author"""
remote_id = self.get_remote_id_from_model(obj)
return self.get_or_create_author(remote_id, instance=obj)
def update_book_from_remote(self, obj):
"""load the remote data from this connector and add it to an existing book"""
remote_id = self.get_remote_id_from_model(obj)
data = self.get_book_data(remote_id)
return self.create_edition_from_data(obj.parent_work, data, instance=obj)
@abstractmethod
def is_work_data(self, data):
"""differentiate works and editions"""
@abstractmethod
def get_edition_from_work_data(self, data):
"""every work needs at least one edition"""
@abstractmethod
def get_work_from_edition_data(self, data):
"""every edition needs a work"""
@abstractmethod
def get_authors_from_data(self, data):
"""load author data"""
@abstractmethod
def expand_book_data(self, book):
"""get more info on a book"""
def dict_from_mappings(data, mappings):
"""create a dict in Activitypub format, using mappings supplies by
the subclass"""
result = {}
for mapping in mappings:
# sometimes there are multiple mappings for one field, don't
# overwrite earlier writes in that case
if mapping.local_field in result and result[mapping.local_field]:
continue
result[mapping.local_field] = mapping.get_value(data)
return result
def get_data(url, params=None, timeout=10):
"""wrapper for request.get"""
# check if the url is blocked
if models.FederatedServer.is_blocked(url):
raise ConnectorException(f"Attempting to load data from blocked url: {url}")
try:
resp = requests.get(
url,
params=params,
headers={
"Accept": "application/json; charset=utf-8",
"User-Agent": settings.USER_AGENT,
},
timeout=timeout,
)
except RequestException as err:
logger.exception(err)
raise ConnectorException()
if not resp.ok:
raise ConnectorException()
try:
data = resp.json()
except ValueError as err:
logger.exception(err)
raise ConnectorException()
return data
def get_image(url, timeout=10):
"""wrapper for requesting an image"""
try:
resp = requests.get(
url,
headers={
"User-Agent": settings.USER_AGENT,
},
timeout=timeout,
)
except RequestException as err:
logger.exception(err)
return None
if not resp.ok:
return None
return resp
class Mapping:
"""associate a local database field with a field in an external dataset"""
def __init__(self, local_field, remote_field=None, formatter=None):
noop = lambda x: x
self.local_field = local_field
self.remote_field = remote_field or local_field
self.formatter = formatter or noop
def get_value(self, data):
"""pull a field from incoming json and return the formatted version"""
value = data.get(self.remote_field)
if not value:
return None
try:
return self.formatter(value)
except: # pylint: disable=bare-except
return None
def infer_physical_format(format_text):
"""try to figure out what the standardized format is from the free value"""
format_text = format_text.lower()
if format_text in format_mappings:
# try a direct match
return format_mappings[format_text]
# failing that, try substring
matches = [v for k, v in format_mappings.items() if k in format_text]
if not matches:
return None
return matches[0]
def unique_physical_format(format_text):
"""only store the format if it isn't diretly in the format mappings"""
format_text = format_text.lower()
if format_text in format_mappings:
# try a direct match, so saving this would be redundant
return None
return format_text