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calibre-web/vendor/PyPDF2/merger.py

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2016-08-07 20:12:32 +00:00
# vim: sw=4:expandtab:foldmethod=marker
#
# Copyright (c) 2006, Mathieu Fenniak
# All rights reserved.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions are
# met:
#
# * Redistributions of source code must retain the above copyright notice,
# this list of conditions and the following disclaimer.
# * Redistributions in binary form must reproduce the above copyright notice,
# this list of conditions and the following disclaimer in the documentation
# and/or other materials provided with the distribution.
# * The name of the author may not be used to endorse or promote products
# derived from this software without specific prior written permission.
#
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
# ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
# LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
# CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
# SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
# INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
# CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
# ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
# POSSIBILITY OF SUCH DAMAGE.
from .generic import *
from .utils import isString, str_
from .pdf import PdfFileReader, PdfFileWriter
from .pagerange import PageRange
from sys import version_info
if version_info < ( 3, 0 ):
from cStringIO import StringIO
StreamIO = StringIO
else:
from io import BytesIO
from io import FileIO as file
StreamIO = BytesIO
class _MergedPage(object):
"""
_MergedPage is used internally by PdfFileMerger to collect necessary
information on each page that is being merged.
"""
def __init__(self, pagedata, src, id):
self.src = src
self.pagedata = pagedata
self.out_pagedata = None
self.id = id
class PdfFileMerger(object):
"""
Initializes a PdfFileMerger object. PdfFileMerger merges multiple PDFs
into a single PDF. It can concatenate, slice, insert, or any combination
of the above.
See the functions :meth:`merge()<merge>` (or :meth:`append()<append>`)
and :meth:`write()<write>` for usage information.
:param bool strict: Determines whether user should be warned of all
problems and also causes some correctable problems to be fatal.
Defaults to ``True``.
"""
def __init__(self, strict=True):
self.inputs = []
self.pages = []
self.output = PdfFileWriter()
self.bookmarks = []
self.named_dests = []
self.id_count = 0
self.strict = strict
def merge(self, position, fileobj, bookmark=None, pages=None, import_bookmarks=True):
"""
Merges the pages from the given file into the output file at the
specified page number.
:param int position: The *page number* to insert this file. File will
be inserted after the given number.
:param fileobj: A File Object or an object that supports the standard read
and seek methods similar to a File Object. Could also be a
string representing a path to a PDF file.
:param str bookmark: Optionally, you may specify a bookmark to be applied at
the beginning of the included file by supplying the text of the bookmark.
:param pages: can be a :ref:`Page Range <page-range>` or a ``(start, stop[, step])`` tuple
to merge only the specified range of pages from the source
document into the output document.
:param bool import_bookmarks: You may prevent the source document's bookmarks
from being imported by specifying this as ``False``.
"""
# This parameter is passed to self.inputs.append and means
# that the stream used was created in this method.
my_file = False
# If the fileobj parameter is a string, assume it is a path
# and create a file object at that location. If it is a file,
# copy the file's contents into a BytesIO (or StreamIO) stream object; if
# it is a PdfFileReader, copy that reader's stream into a
# BytesIO (or StreamIO) stream.
# If fileobj is none of the above types, it is not modified
decryption_key = None
if isString(fileobj):
fileobj = file(fileobj, 'rb')
my_file = True
elif isinstance(fileobj, file):
fileobj.seek(0)
filecontent = fileobj.read()
fileobj = StreamIO(filecontent)
my_file = True
elif isinstance(fileobj, PdfFileReader):
orig_tell = fileobj.stream.tell()
fileobj.stream.seek(0)
filecontent = StreamIO(fileobj.stream.read())
fileobj.stream.seek(orig_tell) # reset the stream to its original location
fileobj = filecontent
if hasattr(fileobj, '_decryption_key'):
decryption_key = fileobj._decryption_key
my_file = True
# Create a new PdfFileReader instance using the stream
# (either file or BytesIO or StringIO) created above
pdfr = PdfFileReader(fileobj, strict=self.strict)
if decryption_key is not None:
pdfr._decryption_key = decryption_key
# Find the range of pages to merge.
if pages == None:
pages = (0, pdfr.getNumPages())
elif isinstance(pages, PageRange):
pages = pages.indices(pdfr.getNumPages())
elif not isinstance(pages, tuple):
raise TypeError('"pages" must be a tuple of (start, stop[, step])')
srcpages = []
if bookmark:
bookmark = Bookmark(TextStringObject(bookmark), NumberObject(self.id_count), NameObject('/Fit'))
outline = []
if import_bookmarks:
outline = pdfr.getOutlines()
outline = self._trim_outline(pdfr, outline, pages)
if bookmark:
self.bookmarks += [bookmark, outline]
else:
self.bookmarks += outline
dests = pdfr.namedDestinations
dests = self._trim_dests(pdfr, dests, pages)
self.named_dests += dests
# Gather all the pages that are going to be merged
for i in range(*pages):
pg = pdfr.getPage(i)
id = self.id_count
self.id_count += 1
mp = _MergedPage(pg, pdfr, id)
srcpages.append(mp)
self._associate_dests_to_pages(srcpages)
self._associate_bookmarks_to_pages(srcpages)
# Slice to insert the pages at the specified position
self.pages[position:position] = srcpages
# Keep track of our input files so we can close them later
self.inputs.append((fileobj, pdfr, my_file))
def append(self, fileobj, bookmark=None, pages=None, import_bookmarks=True):
"""
Identical to the :meth:`merge()<merge>` method, but assumes you want to concatenate
all pages onto the end of the file instead of specifying a position.
:param fileobj: A File Object or an object that supports the standard read
and seek methods similar to a File Object. Could also be a
string representing a path to a PDF file.
:param str bookmark: Optionally, you may specify a bookmark to be applied at
the beginning of the included file by supplying the text of the bookmark.
:param pages: can be a :ref:`Page Range <page-range>` or a ``(start, stop[, step])`` tuple
to merge only the specified range of pages from the source
document into the output document.
:param bool import_bookmarks: You may prevent the source document's bookmarks
from being imported by specifying this as ``False``.
"""
self.merge(len(self.pages), fileobj, bookmark, pages, import_bookmarks)
def write(self, fileobj):
"""
Writes all data that has been merged to the given output file.
:param fileobj: Output file. Can be a filename or any kind of
file-like object.
"""
my_file = False
if isString(fileobj):
fileobj = file(fileobj, 'wb')
my_file = True
# Add pages to the PdfFileWriter
# The commented out line below was replaced with the two lines below it to allow PdfFileMerger to work with PyPdf 1.13
for page in self.pages:
self.output.addPage(page.pagedata)
page.out_pagedata = self.output.getReference(self.output._pages.getObject()["/Kids"][-1].getObject())
#idnum = self.output._objects.index(self.output._pages.getObject()["/Kids"][-1].getObject()) + 1
#page.out_pagedata = IndirectObject(idnum, 0, self.output)
# Once all pages are added, create bookmarks to point at those pages
self._write_dests()
self._write_bookmarks()
# Write the output to the file
self.output.write(fileobj)
if my_file:
fileobj.close()
def close(self):
"""
Shuts all file descriptors (input and output) and clears all memory
usage.
"""
self.pages = []
for fo, pdfr, mine in self.inputs:
if mine:
fo.close()
self.inputs = []
self.output = None
def addMetadata(self, infos):
"""
Add custom metadata to the output.
:param dict infos: a Python dictionary where each key is a field
and each value is your new metadata.
Example: ``{u'/Title': u'My title'}``
"""
self.output.addMetadata(infos)
def setPageLayout(self, layout):
"""
Set the page layout
:param str layout: The page layout to be used
Valid layouts are:
/NoLayout Layout explicitly not specified
/SinglePage Show one page at a time
/OneColumn Show one column at a time
/TwoColumnLeft Show pages in two columns, odd-numbered pages on the left
/TwoColumnRight Show pages in two columns, odd-numbered pages on the right
/TwoPageLeft Show two pages at a time, odd-numbered pages on the left
/TwoPageRight Show two pages at a time, odd-numbered pages on the right
"""
self.output.setPageLayout(layout)
def setPageMode(self, mode):
"""
Set the page mode.
:param str mode: The page mode to use.
Valid modes are:
/UseNone Do not show outlines or thumbnails panels
/UseOutlines Show outlines (aka bookmarks) panel
/UseThumbs Show page thumbnails panel
/FullScreen Fullscreen view
/UseOC Show Optional Content Group (OCG) panel
/UseAttachments Show attachments panel
"""
self.output.setPageMode(mode)
def _trim_dests(self, pdf, dests, pages):
"""
Removes any named destinations that are not a part of the specified
page set.
"""
new_dests = []
prev_header_added = True
for k, o in list(dests.items()):
for j in range(*pages):
if pdf.getPage(j).getObject() == o['/Page'].getObject():
o[NameObject('/Page')] = o['/Page'].getObject()
assert str_(k) == str_(o['/Title'])
new_dests.append(o)
break
return new_dests
def _trim_outline(self, pdf, outline, pages):
"""
Removes any outline/bookmark entries that are not a part of the
specified page set.
"""
new_outline = []
prev_header_added = True
for i, o in enumerate(outline):
if isinstance(o, list):
sub = self._trim_outline(pdf, o, pages)
if sub:
if not prev_header_added:
new_outline.append(outline[i-1])
new_outline.append(sub)
else:
prev_header_added = False
for j in range(*pages):
if pdf.getPage(j).getObject() == o['/Page'].getObject():
o[NameObject('/Page')] = o['/Page'].getObject()
new_outline.append(o)
prev_header_added = True
break
return new_outline
def _write_dests(self):
dests = self.named_dests
for v in dests:
pageno = None
pdf = None
if '/Page' in v:
for i, p in enumerate(self.pages):
if p.id == v['/Page']:
v[NameObject('/Page')] = p.out_pagedata
pageno = i
pdf = p.src
break
if pageno != None:
self.output.addNamedDestinationObject(v)
def _write_bookmarks(self, bookmarks=None, parent=None):
if bookmarks == None:
bookmarks = self.bookmarks
last_added = None
for b in bookmarks:
if isinstance(b, list):
self._write_bookmarks(b, last_added)
continue
pageno = None
pdf = None
if '/Page' in b:
for i, p in enumerate(self.pages):
if p.id == b['/Page']:
#b[NameObject('/Page')] = p.out_pagedata
args = [NumberObject(p.id), NameObject(b['/Type'])]
#nothing more to add
#if b['/Type'] == '/Fit' or b['/Type'] == '/FitB'
if b['/Type'] == '/FitH' or b['/Type'] == '/FitBH':
if '/Top' in b and not isinstance(b['/Top'], NullObject):
args.append(FloatObject(b['/Top']))
else:
args.append(FloatObject(0))
del b['/Top']
elif b['/Type'] == '/FitV' or b['/Type'] == '/FitBV':
if '/Left' in b and not isinstance(b['/Left'], NullObject):
args.append(FloatObject(b['/Left']))
else:
args.append(FloatObject(0))
del b['/Left']
elif b['/Type'] == '/XYZ':
if '/Left' in b and not isinstance(b['/Left'], NullObject):
args.append(FloatObject(b['/Left']))
else:
args.append(FloatObject(0))
if '/Top' in b and not isinstance(b['/Top'], NullObject):
args.append(FloatObject(b['/Top']))
else:
args.append(FloatObject(0))
if '/Zoom' in b and not isinstance(b['/Zoom'], NullObject):
args.append(FloatObject(b['/Zoom']))
else:
args.append(FloatObject(0))
del b['/Top'], b['/Zoom'], b['/Left']
elif b['/Type'] == '/FitR':
if '/Left' in b and not isinstance(b['/Left'], NullObject):
args.append(FloatObject(b['/Left']))
else:
args.append(FloatObject(0))
if '/Bottom' in b and not isinstance(b['/Bottom'], NullObject):
args.append(FloatObject(b['/Bottom']))
else:
args.append(FloatObject(0))
if '/Right' in b and not isinstance(b['/Right'], NullObject):
args.append(FloatObject(b['/Right']))
else:
args.append(FloatObject(0))
if '/Top' in b and not isinstance(b['/Top'], NullObject):
args.append(FloatObject(b['/Top']))
else:
args.append(FloatObject(0))
del b['/Left'], b['/Right'], b['/Bottom'], b['/Top']
b[NameObject('/A')] = DictionaryObject({NameObject('/S'): NameObject('/GoTo'), NameObject('/D'): ArrayObject(args)})
pageno = i
pdf = p.src
break
if pageno != None:
del b['/Page'], b['/Type']
last_added = self.output.addBookmarkDict(b, parent)
def _associate_dests_to_pages(self, pages):
for nd in self.named_dests:
pageno = None
np = nd['/Page']
if isinstance(np, NumberObject):
continue
for p in pages:
if np.getObject() == p.pagedata.getObject():
pageno = p.id
if pageno != None:
nd[NameObject('/Page')] = NumberObject(pageno)
else:
raise ValueError("Unresolved named destination '%s'" % (nd['/Title'],))
def _associate_bookmarks_to_pages(self, pages, bookmarks=None):
if bookmarks == None:
bookmarks = self.bookmarks
for b in bookmarks:
if isinstance(b, list):
self._associate_bookmarks_to_pages(pages, b)
continue
pageno = None
bp = b['/Page']
if isinstance(bp, NumberObject):
continue
for p in pages:
if bp.getObject() == p.pagedata.getObject():
pageno = p.id
if pageno != None:
b[NameObject('/Page')] = NumberObject(pageno)
else:
raise ValueError("Unresolved bookmark '%s'" % (b['/Title'],))
def findBookmark(self, bookmark, root=None):
if root == None:
root = self.bookmarks
for i, b in enumerate(root):
if isinstance(b, list):
res = self.findBookmark(bookmark, b)
if res:
return [i] + res
elif b == bookmark or b['/Title'] == bookmark:
return [i]
return None
def addBookmark(self, title, pagenum, parent=None):
"""
Add a bookmark to this PDF file.
:param str title: Title to use for this bookmark.
:param int pagenum: Page number this bookmark will point to.
:param parent: A reference to a parent bookmark to create nested
bookmarks.
"""
if parent == None:
iloc = [len(self.bookmarks)-1]
elif isinstance(parent, list):
iloc = parent
else:
iloc = self.findBookmark(parent)
dest = Bookmark(TextStringObject(title), NumberObject(pagenum), NameObject('/FitH'), NumberObject(826))
if parent == None:
self.bookmarks.append(dest)
else:
bmparent = self.bookmarks
for i in iloc[:-1]:
bmparent = bmparent[i]
npos = iloc[-1]+1
if npos < len(bmparent) and isinstance(bmparent[npos], list):
bmparent[npos].append(dest)
else:
bmparent.insert(npos, [dest])
return dest
def addNamedDestination(self, title, pagenum):
"""
Add a destination to the output.
:param str title: Title to use
:param int pagenum: Page number this destination points at.
"""
dest = Destination(TextStringObject(title), NumberObject(pagenum), NameObject('/FitH'), NumberObject(826))
self.named_dests.append(dest)
class OutlinesObject(list):
def __init__(self, pdf, tree, parent=None):
list.__init__(self)
self.tree = tree
self.pdf = pdf
self.parent = parent
def remove(self, index):
obj = self[index]
del self[index]
self.tree.removeChild(obj)
def add(self, title, pagenum):
pageRef = self.pdf.getObject(self.pdf._pages)['/Kids'][pagenum]
action = DictionaryObject()
action.update({
NameObject('/D') : ArrayObject([pageRef, NameObject('/FitH'), NumberObject(826)]),
NameObject('/S') : NameObject('/GoTo')
})
actionRef = self.pdf._addObject(action)
bookmark = TreeObject()
bookmark.update({
NameObject('/A'): actionRef,
NameObject('/Title'): createStringObject(title),
})
self.pdf._addObject(bookmark)
self.tree.addChild(bookmark)
def removeAll(self):
for child in [x for x in self.tree.children()]:
self.tree.removeChild(child)
self.pop()