json.decoder.JSONDecodeError: Expecting value: line 1 column 1 (char 0). answer rendring only for 10 characters

Question

@app.route('/api/<string:isbn>', methods = ['GET'])
def isbn(isbn):
#import api from Goodreads (stats)

    book_data = db.execute("SELECT * FROM books WHERE isbn=:isbn",{'isbn':isbn}).fetchone()
    title = book_data['title']
    author = book_data['author']
    year = book_data['year'] 


    res = requests.get("https://www.goodreads.com/book/review_counts.json", params={"key": "4RbGuzka0IUcJWWk1mivqg", "isbns":isbn }).json()

    reviews_count = float(res['books'][0]['reviews_count'])
    avg_score = float(res['books'][0]['average_rating'])
    dic = {"title": title, "author":author, "year": year,"isbn":isbn,"reviews_count":reviews_count,"avg_score":avg_score}
    print(dic)
    return jsonify(dic)

can somebody please tell me what is wrong with this code, when i am specifying 10 characters isbn number it is giving me the right api. when the isbn number i specify is less than 10 characters i am getting internal server error as:

 line 355, in raw_decode
raise JSONDecodeError("Expecting value", s, err.value) from None
json.decoder.JSONDecodeError: Expecting value: line 1 column 1 (char 0)

Answer 1

import requests
isbn = '1590388127'
result = requests.get("https://www.goodreads.com/book/review_counts.json",
                   params={"key": "4RbGuzka0IUcJWWk1mivqg", "isbns": isbn})

if result.status_code == 200:
    res = result.json()
else:  # print reason
    print(result.text)

The upper version works. However with e.g. '756403146' you get the response "'No books match those ISBNs.'" (in result.text). Hence, the isbn is not in the database. If you try to .json() the result of those responses you get the error message you posted.

Answer 2

Googling on the ISBN numbers you could not get to work which were posted in a comment reveals that they seem to have incorrectly had their leading zero dropped. (Many ISBN codes look like numbers, but the last character is often an alphabetic symbol, so you should not be able to handle them as integer values.)

Try padding with leading zeros so the code is always exactly 10 or 13 characters long; any other length is not a valid ISBN.

Probably fix this in the actual database, or even better, in whichever source provided the information in your database; you don't want to have to grapple with corrupted data like this going forward.