bookwyrm/bookwyrm/connectors/connector_manager.py

""" interface with whatever connectors the app has """
import importlib
import re
from urllib.parse import urlparse

from requests import HTTPError

from bookwyrm import models
from bookwyrm.tasks import app


class ConnectorException(HTTPError):
    """ when the connector can't do what was asked """


def search(query, min_confidence=0.1):
    """ find books based on arbitary keywords """
    results = []

    # Have we got a ISBN ?
    isbn = re.sub("[\W_]", "", query)
    maybe_isbn = len(isbn) in [10, 13]  # ISBN10 or ISBN13

    dedup_slug = lambda r: "%s/%s/%s" % (r.title, r.author, r.year)
    result_index = set()
    for connector in get_connectors():
        result_set = None
        if maybe_isbn:
            # Search on ISBN
            if not connector.isbn_search_url or connector.isbn_search_url == "":
                result_set = []
            else:
                try:
                    result_set = connector.isbn_search(isbn)
                except (HTTPError, ConnectorException):
                    pass

        # if no isbn search or results, we fallback to generic search
        if result_set == None or result_set == []:
            try:
                result_set = connector.search(query, min_confidence=min_confidence)
            except (HTTPError, ConnectorException):
                continue

        result_set = [r for r in result_set if dedup_slug(r) not in result_index]
        # `|=` concats two sets. WE ARE GETTING FANCY HERE
        result_index |= set(dedup_slug(r) for r in result_set)
        results.append(
            {
                "connector": connector,
                "results": result_set,
            }
        )

    return results


def local_search(query, min_confidence=0.1, raw=False):
    """ only look at local search results """
    connector = load_connector(models.Connector.objects.get(local=True))
    return connector.search(query, min_confidence=min_confidence, raw=raw)


def isbn_local_search(query, raw=False):
    """ only look at local search results """
    connector = load_connector(models.Connector.objects.get(local=True))
    return connector.isbn_search(query, raw=raw)


def first_search_result(query, min_confidence=0.1):
    """ search until you find a result that fits """
    for connector in get_connectors():
        result = connector.search(query, min_confidence=min_confidence)
        if result:
            return result[0]
    return None


def get_connectors():
    """ load all connectors """
    for info in models.Connector.objects.order_by("priority").all():
        yield load_connector(info)


def get_or_create_connector(remote_id):
    """ get the connector related to the author's server """
    url = urlparse(remote_id)
    identifier = url.netloc
    if not identifier:
        raise ValueError("Invalid remote id")

    try:
        connector_info = models.Connector.objects.get(identifier=identifier)
    except models.Connector.DoesNotExist:
        connector_info = models.Connector.objects.create(
            identifier=identifier,
            connector_file="bookwyrm_connector",
            base_url="https://%s" % identifier,
            books_url="https://%s/book" % identifier,
            covers_url="https://%s/images/covers" % identifier,
            search_url="https://%s/search?q=" % identifier,
            priority=2,
        )

    return load_connector(connector_info)


@app.task
def load_more_data(connector_id, book_id):
    """ background the work of getting all 10,000 editions of LoTR """
    connector_info = models.Connector.objects.get(id=connector_id)
    connector = load_connector(connector_info)
    book = models.Book.objects.select_subclasses().get(id=book_id)
    connector.expand_book_data(book)


def load_connector(connector_info):
    """ instantiate the connector class """
    connector = importlib.import_module(
        "bookwyrm.connectors.%s" % connector_info.connector_file
    )
    return connector.Connector(connector_info.identifier)