novel_epub_parser.py

import json
import multiprocessing
import pathlib

import ebooklib
import typer
from ebooklib import epub
from markdownify import markdownify as md
from transformers import LlamaTokenizer
from nltk import tokenize

pretrained_model_path = '/home/models/NousResearch_Llama-2-13b-hf'
tokenizer = LlamaTokenizer.from_pretrained(pretrained_model_name_or_path=pretrained_model_path)


def queue_worker(q, iolock, max_tokens, min_tokens):
    while True:
        try:
            book, export_folder, error_folder = q.get()
            if book is None:
                break
            book_processor(book, export_folder, error_folder, max_tokens=max_tokens, min_tokens=min_tokens, print_lock=iolock)
        except:
            continue


def add_splits(token_count, max_tokens, text, list, min_tokens):
    if token_count >= min_tokens and token_count <= max_tokens:
        list.append({
            "text": text
        })
    elif token_count > max_tokens:
        sentences = tokenize.sent_tokenize(text)
        if len(sentences) == 1:
            string2 = text[:len(text)//2]
            string1 = text[len(text)//2 if len(text) % 2 == 0
                           else (((len(text)//2))+1):]
        else:
            half_length = len(sentences) // 2
            string2 = "".join(sentences[:half_length])
            string1 = "".join(sentences[half_length:])
        add_splits(len(tokenizer(string2)["input_ids"]),
                   max_tokens, string2, list, min_tokens)
        add_splits(len(tokenizer(string1)["input_ids"]),
                   max_tokens, string1, list, min_tokens)


def book_processor(
    epub_file: pathlib.Path, export_folder: pathlib.Path, error_folder: pathlib.Path, max_tokens: int, min_tokens: int, print_lock=None
):
    if not epub_file.suffix.lower().endswith("epub"):
        return
    try:
        book = epub.read_epub(str(epub_file), options={"ignore_ncx": False})
    except KeyError:
        print("ERROR", epub_file.name, "KeyError & reading_epub")
        epub_file.rename(error_folder / epub_file.name)
        return
    except epub.EpubException as e:
        if "bad zip file" in str(e).lower():
            print("ERROR", epub_file.name, "epub.EpubException, bad zip")
            epub_file.rename(error_folder / epub_file.name)
            return
        print("ERROR", epub_file.name, "epub.EpubException")
        epub_file.rename(error_folder / epub_file.name)
        return
    except Exception as e:
        print("ERROR", epub_file.name, "? Error loading from epub")
        epub_file.rename(error_folder / epub_file.name)
        return
    book_data = {"pages": []}

    epub_pages = []

    for document in book.get_items_of_type(ebooklib.ITEM_DOCUMENT):
        page = md(document.content.decode(encoding="utf-8"))
        epub_pages.append(page)

    epub_pages.pop(0)

    book_data = {"pages": []}

    for page in epub_pages:
        token_count = len(tokenizer(page)["input_ids"])
        if token_count >= min_tokens and token_count <= max_tokens:
            book_data["pages"].append({
            "text": page
        })
        elif token_count > max_tokens:
            add_splits(token_count, max_tokens, page,
                       book_data["pages"], min_tokens)

    empty = 0
    for k in book_data["pages"]:
        if not k:
            empty += 1
    empty = empty/len(book_data["pages"])
    if print_lock:
        with print_lock:
            print("PAGES", epub_file.name, len(book_data["pages"]), "pages")

    with open(export_folder / epub_file.with_suffix(epub_file.suffix + ".jsonl").name, "w") as f:
        f.write('\n'.join([json.dumps(l) for l in [page for page in book_data["pages"]]]))

    if print_lock:
        with print_lock:
            print("FINISHED", epub_file.name)


app = typer.Typer()


@app.command()
def process_books(folder: pathlib.Path, export_folder: pathlib.Path, max_tokens: int, min_tokens: int, error_folder: pathlib.Path = pathlib.Path("errors"), process: int = 64):
    if not error_folder.is_dir():
        error_folder.mkdir(exist_ok=True)
    queue = multiprocessing.Queue(maxsize=process)
    iolock = multiprocessing.Lock()
    pool = multiprocessing.Pool(
        process, initializer=queue_worker, initargs=(
            queue, iolock, max_tokens, min_tokens)
    )
    # iolock = multiprocessing.Lock()
    for i in folder.glob("*.epub"):
        queue.put((i, export_folder, error_folder))
    for _ in range(process):
        queue.put(None)
    pool.close()
    pool.join()


if __name__ == "__main__":
    app()