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A library to manipulate gettext files (po and mo files).

Project description



polib allows you to manipulate, create, modify gettext files (pot, po and mo files). You can load existing files, iterate through it’s entries, add, modify entries, comments or metadata, etc… or create new po files from scratch.

polib is pretty stable now and is used by many opensource projects.


Note: chances are that polib is already packaged for your linux/bsd system, if so, we recommend you use your OS package system, if not then choose a method below:

Installing latest polib version from source tarball

Download latest version

$ tar xzfv polib-x.y.z.tar.gz
$ cd polib-x.y.z
$ python setup build
$ sudo python install

Installing the polib development version

Note: this is not recommended in a production environment.

$ hg clone
$ cd polib
$ python setup build
$ sudo python install

Basic usage example

>>> import polib
>>> # load an existing po file
>>> po = polib.pofile('tests/test_utf8.po')
>>> for entry in po: print entry.msgid, entry.msgstr
>>> # add an entry
>>> entry = polib.POEntry(msgid='Welcome', msgstr='Bienvenue')
>>> entry.occurences = [('', '12'), ('', '34')]
>>> po.append(entry)
>>> # save our modified po file
>>> # compile mo file
>>> po.save_as_mofile('tests/')


A tutorial is available and you can also browse the complete api documentation.


Bugtracker, wiki and mercurial repository can be found at the project’s page. New releases are also published at the cheeseshop.


Version 0.5.4 (2010/10/02)

  • fixed an issue with detect_encoding(), in some cases it could return an invalid charset.

Version 0.5.3 (2010/08/29)

  • correctly unescape lines containing both \n and \n (thanks to Martin Geisler),
  • fixed issue #6: __str__() methods are returning unicode instead of str,
  • fixed issue #8: POFile.merge error when an entry is obsolete in a .po, that this entry reappears in the .pot and that we merge the two,
  • added support to instanciate POFile objects using data instead of file path (thanks to Diego Búrigo Zacarão),
  • fixed issue #9: POFile.merge drop fuzzy attributes from translations (thanks to Tim Gerundt),
  • fixed issue #10: Finding entries with the same msgid and different context (msgctxt).

Version 0.5.2 (2010/06/09)

  • fixed issue #1: untranslated_entries() also show fuzzy message,
  • write back the fuzzy header if present in the pofile,
  • added support for previous msgctxt, previous msgid and previous msgid_plural comments (fixes issue #5),
  • better handling of lines wrapping.

Version 0.5.1 (2009/12/14)

  • fixed issue #0025: requires CHANGELOG but it’s not present in polib-0.5.0-tar.gz

Version 0.5.0 (2009/12/13)

  • fixed issue #0017: UnicodeDecodeError while writing a mo-file,
  • fixed issue #0018: implemented support for msgctxt,
  • fixed bug when compiling plural msgids/strs,
  • API docs are no longer included, hopefully next release will ship with sphinx documentation,
  • parse msg plural entries correctly when reading mo files,
  • fixed issue #0020 and #0021: added ability to check for duplicate when adding entries to po/mo files, this is optional and not enabled by default because it slows down considerably the library,
  • fixed issue #0022: unescaping code is insufficient,
  • fixed issue #0023: encoding error when saving mo file as po file (thanks to sebastien.sable for the patch !).

Version 0.4.2 (2009/06/05)

  • fixed issue #0007: use the codecs module to open files,
  • fixed issue #0014: plural forms are not saved correctly in the mo file (thanks lorenzo.gil.sanchez for the patch),
  • fixed issue #0015: no LICENSE file included in tarball,
  • removed Version/Date from README,
  • added test pot files to,
  • performance improvment in find() method (thanks Thomas !).

Version 0.4.1 (2009/03/04)

  • fixed issue #0006: plural msgstrs were saved unsorted,
  • fixed issue #0008: long comment lines broke ‘save()’ method,
  • removed performance shortcuts: they were in fact inefficient, I was misleaded by the python profile module, kudos to Thomas for making me realise that,
  • fixed issue #0010: wrong polib version number,
  • fixed issue #0011: occurrences parsing is now more robust and can handle weird references formats (like in eToys OLPC po files),
  • fixed issue #0012: improved merge() method.

Version 0.4.0 (2008/11/26)

  • fixed bug #0005: percent_translated divide by 0 on empty po files,
  • fixed bug #0004: occurences that have hiphens are wrapped when they should not,
  • changes in how encoding is handled,
  • remove deprecation warnings for typo “occurences”,
  • added POEntry.__cmp__() method to sort entries like gettext does,
  • fixed POEntry.transalated(),
  • added a merge() method to POFile class, that behaves like the gettext msgmerge utility,
  • obsolete entries are now written at the end of the file and with only msgid/msgstr like gettext does,
  • fixed some bugs in mo files parsing,
  • renamed quote/unquote functions to escape/unescape,
  • various cosmetic changes.

Version 0.3.1 (2007/12/13)

  • fixed bug #0002: typo: “occurences” instead of “occurrences”,
  • fixed bug #0003: mismatch in exception instance names,
  • removed deprecation warnings,
  • removed unused charset() method in POFile/MOFile objects,
  • fixed bug in multibytes string length (added regression tests),
  • fixed a bug in detect_encoding(),
  • added a find() method to _BaseFile class,
  • proper handling of quoting and unquoting,
  • proper handling of multiline strings in metadata

Version 0.3.0 (2007/10/17)

  • speed improvements,
  • polib can now compile mo files,
  • unicode support,
  • fixed bug #0001: global name ‘sorted’ is not defined” on python 2.3.

Version 0.1.0 (2006-08-08)

Initial release

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