A Django command to automatically add translations to po files

potranslate.py

import json
import requests
from django.core.management.base import BaseCommand
from os.path import exists
import polib


class Command(BaseCommand):
    """
    Complete missing and fuzzy translations of po files
    """

    def add_arguments(self, parser):
        parser.add_argument("file", type=str)
        parser.add_argument("from_language", type=str)
        parser.add_argument("to_language", type=str)

    def handle(self, *args, **kwargs):
        po_file = kwargs.get("file")
        from_lang = kwargs.get("from_language")
        to_lang = kwargs.get("to_language")

        if not exists(po_file):
            self.stdout.write("PO file does not exist: " + po_file)
            return

        po = polib.pofile(po_file)
        self.stdout.write("Percentage of translations: " + str(po.percent_translated()))

        if po.percent_translated() == 100:
            self.stdout.write("DONE!")
            return

        lines = self.get_file_lines_as_list(po_file)

        for entry in po.untranslated_entries() + po.fuzzy_entries():
            translation = self.translate(entry.msgid, to_lang, from_lang)
            if translation:
                self.set_value_of_msgid(entry.msgid, translation, lines)
                self.stdout.write(
                    "[Translated] " + entry.msgid + "  ->  " + translation
                )
            else:
                self.stdout.write("[Skipping] " + entry.msgid)

        self.stdout.write("Finished translating. Updating po file ...")

        with open(po_file, "w") as fp:
            for line in lines:
                # write each item on a new line
                if line not in [
                    "#, fuzzy",
                ] and not line.startswith("#|"):
                    fp.write("%s\n" % line)
            self.stdout.write("Finished updating po file")

        self.stdout.write("Done :) please check the PO file since this script can also break things :-s")

    def get_file_lines_as_list(self, filename):
        with open(filename) as file:
            lines_ = file.readlines()
            lines_ = [line_.rstrip() for line_ in lines_]
            return lines_

    def find_index_of_message(self, msgid_, lines_):
        for i in range(0, len(lines_)):
            line_: str = lines_[i]
            if line_.startswith('msgid "' + msgid_):
                return i
        return -1

    def set_value_of_msgid(self, msgid_, value_, lines_):
        i_ = self.find_index_of_message(msgid_, lines_)
        if i_ == -1:
            return
        lines_[i_ + 1] = 'msgstr "{value}"'.format(value=value_)

    def translate(self, text_, to_lang_, from_lang_="en"):
        api = "https://api.mymemory.translated.net/get?q={text}!&langpair={from_}|{to_}".format(
            text=text_, from_=from_lang_, to_=to_lang_
        )
        response_ = requests.get(api)
        response_json = json.loads(response_.text)
        if (
            "responseData" in response_json
            and "translatedText" in response_json["responseData"]
        ):
            return response_json["responseData"]["translatedText"]
        return None

You have to install it as django management command. So under a relative application of your Django project, create a directory called management and place this script there. You can later run it with:

python manage.py potranslate {PATH_TO_PO_FILE} {LANGUAGE FROM} {LANGUAGE TO}

Example:

./manage.py potranslate ./locale/de/LC_MESSAGES/django.po en de

This is awesome. Thanks a lot.