parser.py

from __future__ import unicode_literals
import os
import re
import HTMLParser

from markdown.treeprocessors import Treeprocessor
from markdown.util import etree

from babel.messages.catalog import Catalog
from babel.messages import pofile, mofile
from babel.support import Translations
from six import binary_type

TRANSLATE_TAGS_RE = re.compile('^(li|p|h[1-6]|th|td)$')


class I18NTreeProcessor(Treeprocessor):

    def __init__(self, md, extension):
        self.extension = extension
        super(I18NTreeProcessor, self).__init__(md)
        self.parser = HTMLParser.HTMLParser()

    def translate(self, catalog, translations, root):
        children = root.getchildren()
        for idx, child in enumerate(children):
            if re.match(TRANSLATE_TAGS_RE, child.tag):
                translatable = child.text or ''
                translatable += '\n'.join([
                    etree.tostring(c) for c in
                        child.getchildren()
                ])
                if translatable:
                    translatable = self.parser.unescape(translatable)
                    catalog.add(translatable)
                    attrs = ' '.join((
                        '{}="{}"'.format(k, v) for k, v in child.attrib.items()
                    ))
                    translated = translations.gettext(translatable)

                    if isinstance(translated, binary_type):
                        translated = translated.decode('utf-8')

                    content = '<{0} {2}>{1}</{0}>'.format(
                        child.tag, translated, attrs
                    )
                    try:
                        new_node = etree.fromstring(content.encode('utf-8'))
                        root.remove(child)
                        root.insert(idx, new_node)
                    except etree.ParseError:
                        pass
            else:
                self.translate(catalog, translations, child)

    def run(self, root):

        i18n_dir = self.extension.getConfig('i18n_dir')
        pot_path = os.path.join(i18n_dir, 'messages.pot')

        if os.path.exists(pot_path):
            with open(pot_path, 'r') as f:
                catalog = pofile.read_po(f)
        else:
            catalog = Catalog()

        lang = self.extension.getConfig('i18n_lang')
        mo_path = os.path.join(i18n_dir, lang, 'LC_MESSAGES', 'messages.mo')
        po_path = os.path.join(i18n_dir, lang, 'LC_MESSAGES', 'messages.po')

        if os.path.exists(po_path):
            with open(po_path, 'r') as f:
                lang_catalog = pofile.read_po(f)
            with open(mo_path, 'w') as mo:
                mofile.write_mo(mo, lang_catalog)

        translations = Translations.load(i18n_dir, locales=[lang])
        self.translate(catalog, translations, root)

        with open(pot_path, 'w') as pot_file:
            pofile.write_po(pot_file, catalog)