# class constants:

subjectTag = 'dc:subject'

image_exts = [ ".jpg", ".jpeg", ".gif", ".png", ".svg", ".pdf" ]

def __init__(self, filename=None):

self.zip = None

self.dom = None

self.contentfile = None

if filename:

self.open(filename)

else:

self.filename = None

def open(self, filename):

'''Open an epub file and set up handles to the zip archive

if not zipfile.is_zipfile(filename):

raise RuntimeError(filename + " isn't an epub file (not zipped)")

self.filename = filename

self.zip = zipfile.ZipFile(filename)

self.replace_files = {}

def namelist(self):

return self.zip.namelist()

def parse_contents(self):

# Parse the OPF file into self.dom.

if not self.zip:

raise RuntimeError('Epub book not opened')

for f in self.zip.namelist():

if os.path.basename(f).endswith('.opf'):

if self.contentfile:

raise RuntimeError("Multiple opf files in %s"

% self.filename)

self.contentfile = f

content = self.zip.open(f)

break

if not content:

raise RuntimeError('No .opf file in %s' % self.filename)

return

# Now content is a file handle on the content.opf XML file

try:

self.dom = xml.dom.minidom.parse(content)

except IOError as e:

raise IOError(self.filename + ': ' + str(e))

except xml.parsers.expat.ExpatError as e:

print("Can't parse %s: Expat error, %s" % (self.filename, str(e)),

file=sys.stderr)

content.close()

def close(self):

self.zip.close()

self.filename = None

self.zip = None

self.dom = None

def get_matches(self, elname, delete_tags=False):

'''Find matching tags in the OPF DOM.

if not self.dom:

self.parse_contents()

elements = self.dom.getElementsByTagName(elname)

parent = None

matches = []

for el in elements:

# Obviously there should be more error checking here

if not parent:

parent = el.parentNode

else:

assert parent == el.parentNode

if delete_tags:

if el.childNodes:

print("Deleting:", el.childNodes[0].wholeText)

else:

print("Deleting empty", elname, "tag")

el.parentNode.removeChild(el)

elif el.childNodes:

# el.childNodes[0].wholeText is the unicode.

# Turn it into UTF-8 before returning.

# Uncomment the next line and run on micromegas.epub

# to test a weird thing: it happens if you run

# epubtag.py micromegas.epub | cat

# but not if you just run

# epubtag.py micromegas.epub

# See http://stackoverflow.com/questions/492483/setting-the-correct-encoding-when-piping-stdout-in-python

# matches.append(el.childNodes[0].wholeText)

matches.append(el.childNodes[0].wholeText.encode('utf-8',

'backslashreplace'))

else:

print("Empty", elname, "tag")

return matches, elements, parent

def get_titles(self):

'''Get the title for this work. Returns a list since it's

titles, elements, parent = self.get_matches('dc:title')

return titles

def get_title(self):

'''Get the first (perhaps only) title.

return self.get_titles()[0]

def set_title(self, newtitle):

titles, elements, parent = self.get_matches('dc:title')

for el in elements:

if el.firstChild.nodeType == el.TEXT_NODE:

el.firstChild.replaceWholeText(newtitle)

else:

print("Error: dc:title contains something other than text")

def get_authors(self):

'''Get the list of authors (perhaps only one of them).

authors, elements, parent = self.get_matches('dc:creator')

return authors

def get_tags(self):

'''Get all tags in this epub book.

# Tags are inside <metadata> and look like this:

# <metadata>

# <dc:subject>Presidents -- United States -- Biography</dc:subject>

# Author (dc:creator) and Title (dc:title) are stored similarly.

tags, elements, parent = self.get_matches(self.subjectTag)

return tags

def info_string(self, brief=False):

'''Return an info string describing this book, suitable for printing.

outstr = self.filename + '\n'

# grab the title and author

titles = self.get_titles()

if brief:

outstr += ', '.join(titles) + " | "

else:

for t in titles:

outstr += "Title: " + t + "\n"

authors = self.get_authors()

if brief:

outstr += ', '.join(authors) + ' | '

else:

if len(authors) > 1:

outstr += "Authors: "

else:

outstr += "Author: "

outstr += ', '.join(authors) + "\n"

tags = self.get_tags()

if brief:

outstr += ', '.join(tags)

else:

if tags:

outstr += "Tags: "

for tag in tags:

outstr += '\n ' + tag

return outstr

def delete_tags(self):

'''Delete all tags in the book.

tags, elements, parent = self.get_matches(self.subjectTag, True)

def add_tags(self, new_tag_list):

'''Add the given tags to any tags the epub already has.

tags, elements, parent = self.get_matches(self.subjectTag)

lowertags = [ s.lower() for s in tags ]

# If we didn't see a dc:subject, we still need a parent,

# the <metadata> tag.

if not parent:

print("Warning: didn't see any subject tags previously")

parent = self.dom.getElementsByTagName("metadata")[0]

# If there's no metadata tag, maybe we should add one,

# but it might be better to throw an error.

if not parent:

raise RuntimeError("No metadata tag! Bailing.")

# We'll want to add the new subject tags after the last one.

if elements:

last_tag_el = elements[-1]

else:

last_tag_el = None

for new_tag in new_tag_list:

# Don't add duplicate tags (case-insensitive).

new_tag_lower = new_tag.lower()

if new_tag_lower in lowertags:

print("Skipping duplicate tag", new_tag)

continue

# Make the new node:

#newnode = tag.cloneNode(False)

newnode = self.dom.createElement(self.subjectTag)

# Suddenly all the parsers insist on seeing this element

# in the new dc: tags, which didn't seem to be needed before.

newnode.setAttribute("xmlns:dc", "http://purl.org/dc/elements/1.1/")

# Make a text node inside it:

textnode = self.dom.createTextNode(new_tag)

newnode.appendChild(textnode)

# Also add a newline after each new node

textnode = self.dom.createTextNode('\n')

# Append newnode after the last tag node we saw:

if last_tag_el and last_tag_el.nextSibling:

parent.insertBefore(textnode, last_tag_el.nextSibling)

parent.insertBefore(newnode, textnode)

# If we didn't see a tag, or the tag was the last child

# of its parent, we have to do it this way:

else:

parent.appendChild(newnode)

parent.appendChild(textnode)

print("Adding:", new_tag)

def replace_file(self, oldfilename, newfile):

'''When we save_changes, replace the contents of oldfilename

self.replace_files[oldfilename] = newfile

def save_changes(self):

'''Overwrite the old file with any changes that have been

# Open a new zip file to write to, and copy everything

# but change the content.opf (or whatever.opf) to the new one:

new_epub_file = self.filename + '.tmp'

ozf = zipfile.ZipFile(new_epub_file, 'w')

for info in self.zip.infolist():

if info.filename in self.replace_files:

fp = open(self.replace_files[info.filename])

ozf.writestr(info, fp.read())

fp.close()

elif info.filename == "mimetype":

# The mimetype file must be written uncompressed.

ozf.writestr(info, self.zip.read(info.filename),

zipfile.ZIP_STORED)

elif info.filename.endswith('.opf'):

# dom.toprettyprintxml() returns unicode, which

# zipfile.writestr() can't write. If you pass in

# encoding= then it works ... but minidom gives us

# no way to find out the encoding of the XML file

# we just parsed! So the best we can do is force

# it to UTF-8, barring re-opening the file and

# parsing the first line manually. So crazy!

encoding = 'UTF-8'

ozf.writestr(info, self.dom.toxml(encoding=encoding))

# toprettyxml keeps the old whitespace and also adds

# additional new whitespace ... including trailing

# whitespace on every line. Not best.

# ozf.writestr(info, self.dom.toprettyxml(encoding=encoding,

# indent=" ",

# newl=''))

# This also works:

# ozf.writestr(info,

# self.dom.toprettyxml().encode(encoding,

# 'xmlcharrefreplace'))

else:

# For every other file, just copy directly.

ozf.writestr(info, self.zip.read(info.filename))

ozf.close()

# Now we have the new file in new_epub_file, old in filename.

# Rename appropriately:

bakfile = self.filename + ".bak"

os.rename(self.filename, bakfile)

os.rename(new_epub_file, self.filename)

print("Wrote", self.filename)

os.remove(bakfile)

def extract_cover_image(self, outdir=''):

'''Extract just an image named cover.*.

'''

coverimg = None

parent = self.dom.getElementsByTagName("manifest")[0]

for item in parent.getElementsByTagName("item"):

id = item.getAttribute("id").lower()

if id.startswith("cover"):

coverimg = item.getAttribute("href")

base, ext = os.path.splitext(coverimg)

if ext in self.image_exts:

break

# If it doesn't end with an image type, we can't use it

coverimg = None

# If we didn't find one in the manifest, try looking in guide:

if not coverimg:

guide = self.dom.getElementsByTagName("guide")

if guide:

parent = guide[0]

for item in parent.getElementsByTagName("reference"):

if item.getAttribute("type").lower() == "cover":

coverimg = item.getAttribute("href")

base, ext = os.path.splitext(coverimg)

if ext in self.image_exts:

break

# If it doesn't end with an image type, we can't use it

coverimg = None

# If all else fails, go back to the manifest and look for

# anything named cover.jpg. This is the only recourse for

# many Project Gutenberg books.

if not coverimg:

parent = self.dom.getElementsByTagName("manifest")[0]

for item in parent.getElementsByTagName("item"):

href = item.getAttribute("href")

base, ext = os.path.splitext(os.path.basename(href))

if base.lower() == "cover":

coverimg = href

if not coverimg:

return None, None

infp = None

base = os.path.basename(coverimg)

# If we get here, we think we have the name of the cover image file.

# Unfortunately, it's not necessarily a full path.

# We may need to search for it in the zip.

try:

infp = self.zip.open(coverimg)

except KeyError:

for f in self.zip.namelist():

if os.path.basename(f) == base:

infp = self.zip.open(f)

coverimg = f

if not infp:

print("Couldn't find", coverimg, "in zip archive")

return None, None

outfilename = os.path.join(outdir, base)

outfp = open(outfilename, 'w')

outfp.write(infp.read())

infp.close()

outfp.close()

return outfilename, coverimg

def extract_images(self, outdir=''):

'''Extract all images in the book.

print("Extracting images from", self.filename, end=' ')

if outdir:

print("to", outdir)

else:

print()

for f in self.zip.namelist():

ext = os.path.splitext(f)[-1].lower()

if ext in self.image_exts:

infp = self.zip.open(f)

outfilename = os.path.join(outdir, os.path.basename(f))

i = 1

while os.path.exists(outfilename):

print(os.path.basename(outfilename), "already exists")

se = os.path.splitext(outfilename)

outfilename = se[0] + '-' + str(i) + se[1]

outfp = open(outfilename, 'w')

outfp.write(infp.read())

print("Extracted", f, "to", outfilename)

infp.close()

progname = os.path.basename(sys.argv[0])

print("""Usage: %s file.epub [file.epub...] [-d] [-t tag1 [tag2...]]

-i [dir]: extract images into given directory (default .)""" \

% (progname, progname, progname))