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:pyOleFileIO Module

The :pyOleFileIO module reads Microsoft OLE2 files (also called Structured Storage or Microsoft Compound Document File Format), such as Microsoft Office documents, Image Composer and FlashPix files, and Outlook messages.

This module is the OleFileIO\_PL project by Philippe Lagadec, v0.30, merged back into Pillow.

How to use this module

For more information, see also the file PIL/OleFileIO.py, sample code at the end of the module itself, and docstrings within the code.

About the structure of OLE files

An OLE file can be seen as a mini file system or a Zip archive: It contains streams of data that look like files embedded within the OLE file. Each stream has a name. For example, the main stream of a MS Word document containing its text is named "WordDocument".

An OLE file can also contain storages. A storage is a folder that contains streams or other storages. For example, a MS Word document with VBA macros has a storage called "Macros".

Special streams can contain properties. A property is a specific value that can be used to store information such as the metadata of a document (title, author, creation date, etc). Property stream names usually start with the character '05'.

For example, a typical MS Word document may look like this:

\x05DocumentSummaryInformation (stream)
\x05SummaryInformation (stream)
WordDocument (stream)
Macros (storage)
    PROJECT (stream)
    PROJECTwm (stream)
    VBA (storage)
        Module1 (stream)
        ThisDocument (stream)
        _VBA_PROJECT (stream)
        dir (stream)
ObjectPool (storage)

Test if a file is an OLE container

Use isOleFile to check if the first bytes of the file contain the Magic for OLE files, before opening it. isOleFile returns True if it is an OLE file, False otherwise.

assert OleFileIO.isOleFile('myfile.doc')

Open an OLE file from disk

Create an OleFileIO object with the file path as parameter:

ole = OleFileIO.OleFileIO('myfile.doc')

Open an OLE file from a file-like object

This is useful if the file is not on disk, e.g. already stored in a string or as a file-like object.

ole = OleFileIO.OleFileIO(f)

For example the code below reads a file into a string, then uses BytesIO to turn it into a file-like object.

data = open('myfile.doc', 'rb').read()
f = io.BytesIO(data) # or StringIO.StringIO for Python 2.x
ole = OleFileIO.OleFileIO(f)

How to handle malformed OLE files

By default, the parser is configured to be as robust and permissive as possible, allowing to parse most malformed OLE files. Only fatal errors will raise an exception. It is possible to tell the parser to be more strict in order to raise exceptions for files that do not fully conform to the OLE specifications, using the raise_defect option:

ole = OleFileIO.OleFileIO('myfile.doc', raise_defects=DEFECT_INCORRECT)

When the parsing is done, the list of non-fatal issues detected is available as a list in the parsing_issues attribute of the OleFileIO object:

print('Non-fatal issues raised during parsing:')
if ole.parsing_issues:
    for exctype, msg in ole.parsing_issues:
        print('- %s: %s' % (exctype.__name__, msg))
else:
    print('None')

Syntax for stream and storage path

Two different syntaxes are allowed for methods that need or return the path of streams and storages:

  1. Either a list of strings including all the storages from the root up to the stream/storage name. For example a stream called "WordDocument" at the root will have ['WordDocument'] as full path. A stream called "ThisDocument" located in the storage "Macros/VBA" will be ['Macros', 'VBA', 'ThisDocument']. This is the original syntax from PIL. While hard to read and not very convenient, this syntax works in all cases.
  2. Or a single string with slashes to separate storage and stream names (similar to the Unix path syntax). The previous examples would be 'WordDocument' and 'Macros/VBA/ThisDocument'. This syntax is easier, but may fail if a stream or storage name contains a slash.

Both are case-insensitive.

Switching between the two is easy:

slash_path = '/'.join(list_path)
list_path  = slash_path.split('/')

Get the list of streams

listdir() returns a list of all the streams contained in the OLE file, including those stored in storages. Each stream is listed itself as a list, as described above.

print(ole.listdir())

Sample result:

[['\x01CompObj'], ['\x05DocumentSummaryInformation'], ['\x05SummaryInformation']
, ['1Table'], ['Macros', 'PROJECT'], ['Macros', 'PROJECTwm'], ['Macros', 'VBA',
'Module1'], ['Macros', 'VBA', 'ThisDocument'], ['Macros', 'VBA', '_VBA_PROJECT']
, ['Macros', 'VBA', 'dir'], ['ObjectPool'], ['WordDocument']]

As an option it is possible to choose if storages should also be listed, with or without streams:

ole.listdir (streams=False, storages=True)

Test if known streams/storages exist:

exists(path) checks if a given stream or storage exists in the OLE file.

if ole.exists('worddocument'):
    print("This is a Word document.")
    if ole.exists('macros/vba'):
         print("This document seems to contain VBA macros.")

Read data from a stream

openstream(path) opens a stream as a file-like object.

The following example extracts the "Pictures" stream from a PPT file:

pics = ole.openstream('Pictures')
data = pics.read()

Get information about a stream/storage

Several methods can provide the size, type and timestamps of a given stream/storage:

get_size(path) returns the size of a stream in bytes:

s = ole.get_size('WordDocument')

get_type(path) returns the type of a stream/storage, as one of the following constants: STGTY_STREAM for a stream, STGTY_STORAGE for a storage, STGTY_ROOT for the root entry, and False for a non existing path.

t = ole.get_type('WordDocument')

get_ctime(path) and get_mtime(path) return the creation and modification timestamps of a stream/storage, as a Python datetime object with UTC timezone. Please note that these timestamps are only present if the application that created the OLE file explicitly stored them, which is rarely the case. When not present, these methods return None.

c = ole.get_ctime('WordDocument')
m = ole.get_mtime('WordDocument')

The root storage is a special case: You can get its creation and modification timestamps using the OleFileIO.root attribute:

c = ole.root.getctime()
m = ole.root.getmtime()

Extract metadata

get_metadata() will check if standard property streams exist, parse all the properties they contain, and return an OleMetadata object with the found properties as attributes.

meta = ole.get_metadata()
print('Author:', meta.author)
print('Title:', meta.title)
print('Creation date:', meta.create_time)
# print all metadata:
meta.dump()

Available attributes include:

codepage, title, subject, author, keywords, comments, template,
last_saved_by, revision_number, total_edit_time, last_printed, create_time,
last_saved_time, num_pages, num_words, num_chars, thumbnail,
creating_application, security, codepage_doc, category, presentation_target,
bytes, lines, paragraphs, slides, notes, hidden_slides, mm_clips,
scale_crop, heading_pairs, titles_of_parts, manager, company, links_dirty,
chars_with_spaces, unused, shared_doc, link_base, hlinks, hlinks_changed,
version, dig_sig, content_type, content_status, language, doc_version

See the source code of the OleMetadata class for more information.

Parse a property stream

get_properties(path) can be used to parse any property stream that is not handled by get_metadata. It returns a dictionary indexed by integers. Each integer is the index of the property, pointing to its value. For example in the standard property stream '05SummaryInformation', the document title is property #2, and the subject is #3.

p = ole.getproperties('specialprops')

By default as in the original PIL version, timestamp properties are converted into a number of seconds since Jan 1,1601. With the option convert_time, you can obtain more convenient Python datetime objects (UTC timezone). If some time properties should not be converted (such as total editing time in '05SummaryInformation'), the list of indexes can be passed as no_conversion:

p = ole.getproperties('specialprops', convert_time=True, no_conversion=[10])

Close the OLE file

Unless your application is a simple script that terminates after processing an OLE file, do not forget to close each OleFileIO object after parsing to close the file on disk.

ole.close()

Use OleFileIO as a script

OleFileIO can also be used as a script from the command-line to display the structure of an OLE file and its metadata, for example:

PIL/OleFileIO.py myfile.doc

You can use the option -c to check that all streams can be read fully, and -d to generate very verbose debugging information.

How to contribute

The code is available in a Mercurial repository on bitbucket. You may use it to submit enhancements or to report any issue.

If you would like to help us improve this module, or simply provide feedback, please contact me. You can help in many ways:

  • test this module on different platforms / Python versions
  • find and report bugs
  • improve documentation, code samples, docstrings
  • write unittest test cases
  • provide tricky malformed files

How to report bugs

To report a bug, for example a normal file which is not parsed correctly, please use the issue reporting page, or if you prefer to do it privately, use this contact form. Please provide all the information about the context and how to reproduce the bug.

If possible please join the debugging output of OleFileIO. For this, launch the following command :

PIL/OleFileIO.py -d -c file >debug.txt

Classes and Methods

PIL.OleFileIO