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BookConverter/src/epub_converter/epub_converter.py
2022-10-21 17:07:08 +03:00

606 lines
27 KiB
Python

import re
import ebooklib
from os import path
from pathlib import Path
from ebooklib import epub
from ebooklib.epub import Link, Section
from itertools import chain
from collections import defaultdict
from typing import List, Tuple, Dict, Union
from bs4 import BeautifulSoup, Tag, NavigableString
from src.util.helpers import BookLogger
from src.livecarta_config import LiveCartaConfig
from src.data_objects import ChapterItem, NavPoint
from src.style_reader import StyleReader
from src.epub_converter.html_epub_processor import HtmlEpubProcessor
from src.epub_converter.image_processing import update_images_src_links
from src.epub_converter.footnotes_processing import preprocess_footnotes
from src.inline_style_processor import modify_html_soup_with_css_styles
class EpubConverter:
def __init__(self, book_path, access=None, logger: BookLogger = None,
style_processor: StyleReader = None, html_processor: HtmlEpubProcessor = None):
self.book_path = book_path
self.access = access
self.logger: BookLogger = logger
self.ebooklib_book = epub.read_epub(book_path)
self.style_processor = style_processor
self.html_processor = html_processor
# main container for all epub .xhtml files
self.html_href2html_body_soup: Dict[str, BeautifulSoup] = {}
# enumerate all subchapter id for each file
self.html_href2subchapters_ids = defaultdict(list)
self.hrefs_added_to_toc = set() # enumerate all file paths that where added to TOC
# toc tree structure stored as adj.list (NavPoint to list of NavPoints)
# key = -1 for top level NavPoints
self.adjacency_list: Dict[Union[NavPoint, -1],
Union[List[NavPoint], None]] = {}
# list to offset Chapter_i on 1st level
self.offset_sub_nodes = []
# container for all chapters soup objects
# here soup object is only part of the .xhtml file
self.href_chapter_id2soup_html: Dict[tuple, BeautifulSoup] = {}
self.internal_anchors = set()
# flag to be updated while ebooklib.toc is parsed
self.id_anchor_exist_in_nav_points = False
self.img_href2img_bytes = {} # file path to bytes
# file path from <a> to generated aws path
self.book_image_src_path2aws_path = {}
self.footnotes_contents: List[str] = [] # to be sent on server as is
self.noterefs: List[Tag] = [] # start of the footnote
self.footnotes: List[Tag] = [] # end of the footnote
self.logger.log("HTML files reading.")
self.html_href2html_body_soup: Dict[str,
BeautifulSoup] = self.build_href2soup_content()
self.logger.log("CSS inline style processing.")
[self.style_processor.process_inline_styles_in_html_soup(
self.html_href2html_body_soup[html_href]) for html_href in self.html_href2html_body_soup]
self.logger.log("CSS files processing.")
self.html_href2css_href, self.css_href2css_content = self.build_html_and_css_relations()
self.logger.log("CSS styles fusion(inline+file).")
self.add_css_styles_to_html_soup()
self.logger.log("Image processing.")
for x in chain(self.ebooklib_book.get_items_of_type(ebooklib.ITEM_IMAGE),
self.ebooklib_book.get_items_of_type(ebooklib.ITEM_COVER)):
file_name = x.file_name
content = x.content
self.img_href2img_bytes[file_name] = content
self.logger.log("Footnotes processing.")
for href in self.html_href2html_body_soup:
self.footnotes_contents, self.noterefs, self.footnotes =\
preprocess_footnotes(
self.html_href2html_body_soup[href], self.html_href2html_body_soup)
self.logger.log(f"Added {len(self.footnotes_contents)} footnotes.")
self.logger.log("TOC processing.")
self.build_adjacency_list_from_toc(self.ebooklib_book.toc)
# build simple toc from spine if needed
if self.is_toc_empty():
self.build_adjacency_list_from_spine()
not_added = [
x for x in self.html_href2html_body_soup if x not in self.hrefs_added_to_toc]
self.logger.log(f"Html documents not added to TOC: {not_added}.")
self.logger.log(f"Add documents not added to TOC.")
self.add_not_added_files_to_adjacency_list(not_added)
self.logger.log(f"Label subchapters with converter tag.")
self.label_subchapters_with_lc_tag()
self.logger.log(f"Process html internal links.")
self.process_internal_links()
self.logger.log(
f"Check if converter-chapter-marks are on the same level.")
self.chapter_marks_are_same_level()
self.logger.log(f"Define chapters content.")
self.define_chapters_with_content()
self.logger.log(f"Converting html_nodes to LiveCarta chapter items.")
def build_href2soup_content(self) -> Dict[str, BeautifulSoup]:
# using EpubElements
# for now just for HTML objects, as it is the simplest chapter
nodes = dict()
for item in self.ebooklib_book.get_items_of_type(ebooklib.ITEM_DOCUMENT):
html_body_text = item.get_body_content()
# html.parser closes tags if needed
soup = BeautifulSoup(html_body_text, features="html.parser")
nodes[item.file_name] = soup
return nodes
def build_html_and_css_relations(self) -> Tuple[Dict[str, List[str]], Dict[str, str]]:
"""
Function is designed to get 2 dictionaries:
The first is html_href2css_href. It is created to connect href of html to css files(hrefs of them
) which are used on this html
The second is css_href2css_content. It is created to connect href of css to content of css
...2... = key2value
Returns
----------
html_href2css_href, css_href2css_content: tuple[dict, dict]
dictionary: href of html to related css files, dictionary: css files to related css content
"""
# dictionary: href of html to related css files
html_href2css_href: Dict[str, List[str]] = defaultdict(list)
css_href2css_content: Dict[str, str] = {}
for item in self.ebooklib_book.get_items_of_type(ebooklib.ITEM_DOCUMENT):
html_content = item.content
html_href = item.file_name
soup_html_content = BeautifulSoup(html_content, features="lxml")
# check if file links to css file
for tag in soup_html_content.find_all("link", attrs={"type": "text/css"}):
# alternate page of original page (e.g. another language)
if tag.attrs.get("rel") and ("alternate" in tag.attrs["rel"]):
continue
css_href = tag.attrs.get("href")
html_href2css_href[html_href].append(css_href)
if css_href not in css_href2css_content:
# css_href not in css_href2css_content, add to this dict
css_href2css_content[css_href] = self.style_processor.build_css_file_content(
self.style_processor.get_css_content(css_href, html_href, self.ebooklib_book))
for i, tag in enumerate(soup_html_content.find_all("style")):
css_content = tag.string
html_href2css_href[html_href].append(f"href{i}")
css_href2css_content[f"href{i}"] = self.style_processor.build_css_file_content(
css_content)
return html_href2css_href, css_href2css_content
def add_css_styles_to_html_soup(self):
"""
This function is designed to update html_href2html_body_soup
- add to html_inline_style css_style_content
Returns
-------
None
updated soups with styles from css
"""
for html_href in self.html_href2html_body_soup:
if self.html_href2css_href.get(html_href):
css = ""
for css_href in self.html_href2css_href[html_href]:
css += self.css_href2css_content[css_href]
html_content: BeautifulSoup = self.html_href2html_body_soup[html_href]
html_content = modify_html_soup_with_css_styles(
html_content, css)
self.html_href2html_body_soup[html_href] = html_content
def build_adjacency_list_from_toc(self,
element: Union[Link, Tuple[Section, List], List[Union[Link, Tuple]]],
lvl: int = 0) -> NavPoint:
"""
Function
self.adjacency_list builds based on TOC nested structure, got from self.ebooklib.toc
key = -1 if root(top chapters),
value = None if leaf(the least chapters)
Parameters
----------
element: [Link, tuple, list]
element that appears in TOC(usually parsed from nav.ncx)
lvl: int
level of node
Returns
----------
None
built adjacency list
"""
if isinstance(element, Link):
nav_point = NavPoint(element)
if nav_point.id:
self.id_anchor_exist_in_nav_points = True
self.html_href2subchapters_ids[nav_point.href].append(
nav_point.id)
self.adjacency_list[nav_point] = None
self.hrefs_added_to_toc.add(nav_point.href)
return nav_point
elif isinstance(element, tuple):
first, second = element
assert isinstance(first, Section)
nav_point = NavPoint(first)
if nav_point.id:
self.id_anchor_exist_in_nav_points = True
self.html_href2subchapters_ids[nav_point.href].append(
nav_point.id)
sub_nodes = []
for elem in second:
if (bool(re.search("^section$|^part$", first.title.lower()))) and lvl == 1:
self.offset_sub_nodes.append(
self.build_adjacency_list_from_toc(elem, lvl))
else:
sub_nodes.append(
self.build_adjacency_list_from_toc(elem, lvl + 1))
self.adjacency_list[nav_point] = sub_nodes
self.hrefs_added_to_toc.add(nav_point.href)
return nav_point
elif isinstance(element, list) and (lvl == 0):
nodes = []
# add through every element
for elem in element:
nodes.append(
self.build_adjacency_list_from_toc(elem, lvl + 1))
# set chapter_i after Section & add through every offset sub element
for offset_sub_node in self.offset_sub_nodes:
nodes.append(offset_sub_node)
self.offset_sub_nodes = []
self.adjacency_list[-1] = nodes
else:
assert 0, f"Error. Element is not tuple/Link/list instance: {type(element)}"
def is_toc_empty(self) -> bool:
"""Function checks is toc empty"""
# there is no toc in ebook or no top chapters
if (self.ebooklib_book.toc is None) or (self.adjacency_list.get(-1) is None):
return True
return False
def build_adjacency_list_from_spine(self):
def build_manifest_id2html_href() -> Dict[int, str]:
links = dict()
for item in self.ebooklib_book.get_items_of_type(ebooklib.ITEM_DOCUMENT):
links[item.id] = item.file_name
return links
manifest_id2html_href = build_manifest_id2html_href()
self.adjacency_list = {
-1: []
}
for id_, _ in self.ebooklib_book.spine:
nav_point = NavPoint(
Section(manifest_id2html_href[id_], manifest_id2html_href[id_]))
self.adjacency_list[-1].append(nav_point)
self.hrefs_added_to_toc.add(nav_point.href)
def add_not_added_files_to_adjacency_list(self, not_added: List[str]):
"""Function add files that not added to adjacency list"""
for i, file in enumerate(not_added):
nav_point = NavPoint(
Section(f"To check #{i}, filename: {file}", file))
self.adjacency_list[-1].append(nav_point)
self.hrefs_added_to_toc.add(file)
def label_subchapters_with_lc_tag(self):
for html_href in self.html_href2html_body_soup:
ids, soup = self.html_href2subchapters_ids[html_href], \
self.html_href2html_body_soup[html_href]
for i in ids:
tag = soup.find(id=i)
tmp_tag = soup.new_tag("lc_tmp")
tmp_tag.attrs["class"] = "converter-chapter-mark"
tmp_tag.attrs["id"] = i
tag.insert_before(tmp_tag)
def chapter_marks_are_same_level(self):
"""
Function checks that marks for pointing a start of a chapter are placed on one level in html tree.
Mark is tag with "class": "converter-chapter-mark". Added while TOC was parsed.
This tag must have a chapter_tag as a parent.
Otherwise, it is wrapped with some tags. Like:
<p> <span id="123", class="converter-chapter-mark"> </span> </p>
"""
for html_href in self.html_href2html_body_soup:
chapter_tag = self.html_href2html_body_soup[html_href]
# check marks for chapter starting are on the same level - 1st
marks = chapter_tag.find_all(
attrs={"class": "converter-chapter-mark"})
# fix marks to be on 1 level
for mark in marks:
while mark.parent != chapter_tag:
# todo warning! could reflect on formatting/internal links in some cases
mark.parent.unwrap()
@staticmethod
def create_unique_id(href: str, id_: str) -> str:
return "id" + re.sub(r'[\W_]+', "", href) + re.sub(r'[\W_]+', "0", id_)
def match_href_to_path_from_toc(self,
cur_file_path: str,
href_in_link: str,
internal_link_tag: Tag) -> Union[None, str]:
"""
Function used to find full path to file that is parsed from tag link
TOC: a/b/c.xhtml
b/c.xhtml -> a/b/c.xhtml
c.xhtml -> a/b/c.xhtml
Parameters
----------
cur_file_path: str
path to current file with tag link
href_in_link: str
filename got from tag link, like file1.xhtml
internal_link_tag: Tag
object that is parsed now
Returns
-------
full_path[0]: str
prepared content
"""
dir_name = path.dirname(cur_file_path)
normed_path = path.normpath(path.join(
dir_name, href_in_link)).replace("\\", "/")
full_path = [
path for path in self.hrefs_added_to_toc if normed_path in path]
if not full_path:
self.logger.log(f"Error in {cur_file_path} file. No {normed_path} file found in added to TOC documents. "
f"While processing href in {internal_link_tag}.")
internal_link_tag.attrs["converter-mark"] = "bad-link"
return None
if len(full_path) > 1:
self.logger.log(f"Warning in {cur_file_path}. Multiple paths found {full_path} for file {href_in_link}"
f" while {internal_link_tag} processing. The first one will be chosen.")
return full_path[0]
@staticmethod
def create_new_anchor_span(soup: BeautifulSoup, id_: str) -> Tag:
new_anchor_span = soup.new_tag("span")
new_anchor_span.attrs["id"] = id_
new_anchor_span.attrs["class"] = "link-anchor"
new_anchor_span.string = "\xa0"
return new_anchor_span
def process_internal_links(self):
"""
Function
- processing internal links in a book
- make ids unique
Steps
----------
1. rebuild ids to be unique in all documents
2a. process anchor which is a whole htm|html|xhtml file
2b. process anchor which is an element in htm|html|xhtml file
Returns
-------
None
process links in html
"""
def make_ids_unique():
for toc_href in self.hrefs_added_to_toc:
for tag in self.html_href2html_body_soup[toc_href].find_all(attrs={"id": re.compile(r".+")}):
if tag.attrs.get("class") not in ["converter-chapter-mark", "footnote-element"]:
new_id = self.create_unique_id(
toc_href, tag.attrs["id"])
tag.attrs["id"] = new_id
def process_file_anchor():
for toc_href in self.hrefs_added_to_toc:
soup = self.html_href2html_body_soup[toc_href]
for internal_link_tag in soup.find_all("a",
{"href": re.compile(r"(^(?!https?://).+\.(htm|html|xhtml)$)")}):
a_tag_href = internal_link_tag.attrs["href"]
a_tag_href_matched_to_toc = self.match_href_to_path_from_toc(
toc_href, a_tag_href, internal_link_tag)
if a_tag_href_matched_to_toc:
new_id = self.create_unique_id(
a_tag_href_matched_to_toc, "")
internal_link_tag.attrs["placeholder"] = "{{tempStyleToAnchor-" + new_id + "}}"
if new_id not in self.internal_anchors:
anchor_soup = self.html_href2html_body_soup[a_tag_href_matched_to_toc]
new_anchor_span = self.create_new_anchor_span(
soup, new_id)
# insert a new span to the beginning of the file
anchor_soup.insert(0, new_anchor_span)
self.internal_anchors.add(new_id)
del internal_link_tag.attrs["href"]
def process_file_element_anchor():
for toc_href in self.hrefs_added_to_toc:
soup = self.html_href2html_body_soup[toc_href]
# process_file_element_anchor
for internal_link_tag in soup.find_all("a", {"href": re.compile(r"(^.+\.(htm|html|xhtml)#.+)|(^#.+)")}):
a_tag_href, a_tag_id = internal_link_tag.attrs["href"].split(
"#")
a_tag_href_matched_to_toc = self.match_href_to_path_from_toc(
toc_href, a_tag_href, internal_link_tag) if a_tag_href \
else path.normpath(toc_href).replace("\\", "/")
if a_tag_href_matched_to_toc:
new_id = self.create_unique_id(
a_tag_href_matched_to_toc, a_tag_id)
anchor_soup = self.html_href2html_body_soup[a_tag_href_matched_to_toc]
anchor_tags = anchor_soup.find_all(attrs={"id": new_id}) or \
anchor_soup.find_all(
attrs={"id": a_tag_id}) # if link is a footnote
if anchor_tags:
if len(anchor_tags) > 1:
self.logger.log(f"Warning in {toc_href}: multiple anchors:"
f"{len(anchor_tags)} found.\n"
f"{anchor_tags}\n"
f"While processing {internal_link_tag}")
anchor_tag = anchor_tags[0]
assert anchor_tag.attrs["id"] in [new_id, a_tag_id]
# if anchor is found we could add placeholder for link creation on server side.
internal_link_tag.attrs["placeholder"] = "{{tempStyleToAnchor-" + new_id + "}}"
# create span to have cyclic links, link has 1 type of class, anchor another
if anchor_tag.attrs["id"] not in self.internal_anchors:
new_anchor_span = self.create_new_anchor_span(
soup, new_id)
anchor_tag.insert_before(new_anchor_span)
self.internal_anchors.add(new_id)
del anchor_tag.attrs["id"]
del internal_link_tag.attrs["href"]
else:
internal_link_tag.attrs["converter-mark"] = "bad-link"
self.logger.log(f"Error in {toc_href}."
f" While processing {internal_link_tag} no anchor found."
f" Should be anchor with new id={new_id} in"
f" {a_tag_href_matched_to_toc} file."
f" Old id={a_tag_id}")
# 1. make ids to be unique in all documents
make_ids_unique()
# 2a. process anchor which is a whole htm|html|xhtml file
process_file_anchor()
# 2b. process anchor which is an element in htm|html|xhtml file
process_file_element_anchor()
@staticmethod
def get_tags_between_chapter_marks(first_id: str,
href: str,
html_soup: BeautifulSoup) -> List[Union[Tag, NavigableString]]:
"""
Get tags between LiveCarta chapter marks
Parameters
----------
first_id: str
Id that point where a chapter starts. A Tag with class: "converter-chapter-mark"
href: str
Name of current chapters file
html_soup: Tag
Soup object of current file
Returns
-------
tags: list [Tag, NavigableString]
Chapter's tags
"""
marked_tags = html_soup.find(
attrs={"id": first_id, "class": "converter-chapter-mark"})
if marked_tags:
next_tag = marked_tags.next_sibling
tags = []
while next_tag:
if not isinstance(next_tag, NavigableString) and \
(next_tag.attrs.get("class") == "converter-chapter-mark"):
break
tags.append(next_tag)
next_tag = next_tag.next_sibling
# remove tags between first_id and next found id
# save them in list for next steps
tags = [tag.extract() for tag in tags]
html_soup.smooth()
else:
assert 0, f"Warning: no match for {first_id, href}"
return tags
def detect_one_chapter(self, nav_point: NavPoint):
"""
Function updates self.href_chapter_id2soup_html (mapping from (href,id) to chapter content/html soup object)
3 cases:
id wraps all chapter content,
id wraps chapter"s content + subchapters" content
id points to the start of title of a chapter
In all cases we know where chapter starts. Therefore, chapter is all tags between chapter's id
and id of the next chapter/subchapter
Parameters
----------
nav_point: NavPoint
Returns
-------
None
built chapter
"""
if nav_point.id:
soup = self.html_href2html_body_soup[nav_point.href]
subchapter_tags = self.get_tags_between_chapter_marks(
first_id=nav_point.id, href=nav_point.href, html_soup=soup)
new_tree = BeautifulSoup("", "html.parser")
for subchapter_tag in subchapter_tags:
new_tree.append(subchapter_tag)
self.href_chapter_id2soup_html[(
nav_point.href, nav_point.id)] = new_tree
if self.adjacency_list.get(nav_point):
for sub_node in self.adjacency_list[nav_point]:
self.detect_one_chapter(sub_node)
def define_chapters_with_content(self):
"""Function build chapters content, starts from top level chapters"""
top_level_nav_points = self.adjacency_list[-1]
if self.id_anchor_exist_in_nav_points:
for tl_nav_point in top_level_nav_points:
self.detect_one_chapter(tl_nav_point)
def html_node_to_livecarta_chapter_item(self, nav_point: NavPoint, lvl: int = 1) -> ChapterItem:
"""
Function prepare style, tags to json structure
Parameters
----------
nav_point: NavPoint
lvl: int
level of chapter
Returns
-------
ChapterItem
built chapter
"""
title: str = nav_point.title
content: BeautifulSoup = self.href_chapter_id2soup_html[(nav_point.href, nav_point.id)] \
if nav_point.id else self.html_href2html_body_soup[nav_point.href]
indent: str = " " * lvl
self.logger.log(indent + f"Chapter: {title} is processing.")
is_chapter: bool = lvl <= LiveCartaConfig.SUPPORTED_LEVELS
self.logger.log(indent + "Process title.")
title_preprocessed: str = self.html_processor.prepare_title(title)
self.logger.log(indent + "Process content.")
content_preprocessed: Union[Tag, BeautifulSoup] = self.html_processor.prepare_content(
title_preprocessed, content, remove_title_from_chapter=is_chapter)
self.book_image_src_path2aws_path = update_images_src_links(content_preprocessed,
self.img_href2img_bytes,
path_to_html=nav_point.href,
access=self.access,
path2aws_path=self.book_image_src_path2aws_path,
book_id=Path(self.book_path).stem)
sub_nodes = []
# warning! not EpubHtmlItems won't be added to chapter
# if it doesn't have subchapters
if self.adjacency_list.get(nav_point):
for sub_node in self.adjacency_list[nav_point]:
sub_chapter_item = self.html_node_to_livecarta_chapter_item(
sub_node, lvl + 1)
sub_nodes.append(sub_chapter_item)
return ChapterItem(title_preprocessed, str(content_preprocessed), sub_nodes)
def convert_to_dict(self) -> Dict[str, List[Dict[str, Union[List, str]]]]:
"""Function which convert list of html nodes to appropriate json structure"""
top_level_nav_points = self.adjacency_list[-1]
top_level_chapters = []
# loop through to level chapters
for tl_nav_point in top_level_nav_points:
chapter = self.html_node_to_livecarta_chapter_item(tl_nav_point)
top_level_chapters.append(chapter)
top_level_dict_chapters = [x.to_dict() for x in top_level_chapters]
self.logger.log(f"Anchors found: {len(self.internal_anchors)}.")
self.logger.log("End conversion.")
return {
"content": top_level_dict_chapters,
"footnotes": self.footnotes_contents
}