Plugins¶
Plugins can be used to automate some of the workflow. For instance ebooklib.plugins.tidyhtml
plugins automatically cleans HTML
output for you. FootnotePlugin for instance rewrites custom footnotes into EPUB3 kind of footnotes. Without these plugins you would
need to do wanted transformations before setting or getting content from your chapters.
There is a ebooklib.plugins.base.BasePlugin
class which you need to extend. These are the methods you can override.
Method | Arguments | Description |
---|---|---|
before_write | book | Processing before book save |
after_write | book | Processing after book save |
before_read | book | Processing before book read |
after_read | book | Processing after book read |
item_after_read | book, item | Process general item after read |
item_before_write | book, item | Process general item before write |
html_after_read | book, chapter | Processing HTML before read |
html_before_write | book, chapter | Processing HTML before save |
Custom plugin¶
This is our use case. We have online WYSIWYG editing system for editing content of our books. In the editor to link to our other page we use this syntax <a href=”../page/”>Our page</a> but in the EPUB book we would need to link to page.xhtml file for instance.
We could do the transformations manually or we could write a plugin which does all of the work for us. We override html_before_write method. We parse the content of our chapter, find all links, replace them with new href and finally set new content to the chapter.
try:
from urlparse import urlparse, urljoin
except ImportError:
from urllib.parse import urlparse, urljoin
from lxml import etree
from ebooklib.plugins.base import BasePlugin
from ebooklib.utils import parse_html_string
class MyeLinks(BasePlugin):
NAME = 'My Links'
def html_before_write(self, book, chapter):
try:
tree = parse_html_string(chapter.content)
except:
return
root = tree.getroottree()
if len(root.find('body')) != 0:
body = tree.find('body')
for _link in body.xpath('//a'):
_u = urlparse(_link.get('href', ''))
# Let us care only for internal links at the moment
if _u.scheme == '':
if _u.path != '':
_link.set('href', '%s.xhtml' % _u.path)
if _u.fragment != '':
_link.set('href', urljoin(_link.get('href'), '#%s' % _u.fragment))
if _link.get('name') != None:
_link.set('id', _link.get('name'))
etree.strip_attributes(_link, 'name')
chapter.content = etree.tostring(tree, pretty_print=True, encoding='utf-8')
When you want to use it just pass the list of plugins you want to use as extra option to the write_epub method (also to read_epub method). Plugins will be executed in the order they are defined in the list.
epub.write_epub('test.epub', book, {"plugins": [MyLinks()]})