如何使用 python ISBNLIB 元方法捕获错误并继续

Question

我有一个使用 FLASK 和 ISBNLIB 库的简单应用程序，该应用程序获取条形码和 isbn 编号，搜索 ISBN 并将信息插入数据库。

isbnlib 元方法搜索 ISBN，然后将其插入到我的 sqlite 数据库中。

我遇到的问题是当找不到那本书时我收到一条错误消息：

isbnlib.dev._exceptions.NoDataForSelectorError

我想要实现的是让应用程序捕获此错误并仍然将我的条形码和 isbn 插入数据库并在其他字段中输入空值。

我不确定如何解决这个问题。

如有任何建议，我们将不胜感激。

代码如下：

else:
    # Assign meta dictionary to book_lib for value calling.
    book_lib = (isbnlib.meta(isbn, service='goob', cache='default'))

    # Display meta data to user.
    flash(isbnlib.meta(isbn, service='goob', cache='default'))

    # Assign meta dictionary values to variables for insertion to DB.
    author = str(book_lib['Authors'])
    lang = book_lib['Language']
    publisher = book_lib['Publisher']
    title = book_lib['Title']
    publYear = book_lib['Year']

    db.execute(
        'INSERT INTO new_book (barcode, isbn, invoice, author_id, author, lang, publisher, title, publYear)'
        ' VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?)',
        (barcode, isbn, invoice, g.user['id'], author, lang, publisher, title, publYear)
    )
    db.commit()
    return redirect(url_for('book.newbook'))

Answer 1

与此类似的内容应该适合您：

from isbnlib.dev._exceptions import NoDataForSelectorError


else:
    # Assign meta dictionary to book_lib for value calling.
    author = None
    lang = None
    publisher = None
    title = None
    publYear = None

    try:
        book_lib = isbnlib.meta(isbn, service='goob', cache='default')
        # Display meta data to user.
        flash(book_lib)

        # Assign meta dictionary values to variables for insertion to DB.
        author = str(book_lib['Authors'])
        lang = book_lib['Language']
        publisher = book_lib['Publisher']
        title = book_lib['Title']
        publYear = book_lib['Year']

    except NoDataForSelectorError:
        pass

    db.execute(
        'INSERT INTO new_book (barcode, isbn, invoice, author_id, author, lang, publisher, title, publYear)'
        ' VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?)',
        (barcode, isbn, invoice, g.user['id'], author, lang, publisher, title, publYear)
    )
    db.commit()
    return redirect(url_for('book.newbook'))

Answer 2

这可行（目前）但不可取，因为它使用了不受支持的 api!

改为使用 catch-all isbnlib 异常

from isbnlib import ISBNLibException

或特定的

from isbnlib.dev import NoDataForSelectorError

如何使用 python ISBNLIB 元方法捕获错误并继续

how to catch an error using the python ISBNLIB meta method and continue

python

sqlite

error-handling

flask

isbnlib