[Shohreh]

It works, but www.isbn.nu is missing a lot of non-English books. I'll have to find a better source (Amazon probably).

#pip install beautifulsoup4
#pip install lxml
from bs4 import BeautifulSoup
import requests
import sqlite3
import re

"""
First, scan ISBN with barcode scanner into plain text file

sqlite3.exe books.sqlite
CREATE TEMP TABLE temp_books(isbn TEXT);
.import input.txt temp_books
CREATE TABLE IF NOT EXISTS books(isbn TEXT,title TEXT, year TEXT);
INSERT INTO books(isbn) SELECT isbn FROM temp_books;
CREATE TABLE IF NOT EXISTS authors(isbn TEXT,author TEXT);
DROP TABLE temp_books;
.quit
"""

pattern_year = re.compile('(\d{4})')

db = sqlite3.connect('books.sqlite')
cursor = db.cursor()
cursor.execute('BEGIN')
with open('input.txt') as reader:
	for line in reader:
		isbn = line.strip()
		print(f"Handling {isbn}")

		url = f"https://isbn.nu/{isbn}"
		page = requests.get(url)
		soup = BeautifulSoup(page.content, 'html.parser')
		#title
		title=soup.title.string
		if title == "No Title Found":
			title = None
		print("Title=",title)
		#Year published
		for col in soup.find_all("div", {"class": "bi_row"}):
			if col.find("span", {"class": "bi_col_title"}).text == "Publication date":
				date = col.find("span", {"class": "bi_col_value"}).text 
				#Extract year
				m = pattern_year.search(date)
				if m:
					year = m.group(0) #Not (1)?
					print("Date=", year)
				else:
					print("Date not found")
				break
		cursor.execute("UPDATE books SET title= ? , year=? WHERE isbn=?", (title,year,isbn))
		
		#author(s)
		authors = soup.select("a[href*=authorx]")
		for author in authors:
			name=author.string
			author = author.string
			cursor.execute("UPDATE authors SET author= ?  WHERE isbn=?", (author,isbn))
			
cursor.execute('END')
db.commit()
db.close()

print("Done.")