sl10n 0.1.0.1

Static localization system that reduces a headache of working with localization

sl10n

sl10n is a library that takes a unique approach to dealing with localization by using statically typed translation keys.

Features

• Type-safe: we use statically typed translation keys, so you don't have to worry about making a typo or using a wrong key.
• Explicit: you get the exact result that you expect.
• Versatile: you can use it in any project.
• Self-sufficient, no other tools required.
• Written purely on Python.
• Easy to use.
• Small.

Why?

Imagine you have a lang folder containing all our translation files and a parser that reads these files and stores them in mapping.

{
    "my_key_1": "My text",
    "my_key_2": "Wrong text"
}

import parser  # your handwritten parser

locales = parser.parse('/lang')
locale = locales.get('en')

print(locale.get('my_key_1'))  # My text

You may probably think "Sounds pretty simple" and you'd be right. This approach is pretty common (e.g., Minecraft mods use it).

But it's really error-prone. You can easily make a typo or refer to a different key with similar name.

print(locale.get('my_key_I'))  # my_key_I
print(locale.get('my_key_2'))  # Wrong text

This becomes a real trouble once you change the schema of your translation files and even IDEs won't help you.

So?

sl10n fixes this by introducing locale containers.

In short, a locale container is a spec of your translation files that contains all possible keys. At parsing, all your localization gets collected into locale containers, so you can access them freely.

sl10n defines a base class for your locale container (SLocale) and a parsing system (SL10n).

from sl10n import SL10n, SLocale


class MyLocale(SLocale):  # your locale container, it MUST inherit from SLocale
    my_key_1: str
    my_key_2: str


l10n = SL10n(MyLocale, 'lang')  # creating a reference for system

l10n.init()  # execute parser

The key difference is that now you can access your translated strings as class attributes.

locale: MyLocale = l10n.locale('en')  # returns default one if this language wasn't found

print(locale.my_key_1)  # My text

That way, your IDE can suggest what keys you can use and also tell you if you made a typo.

print(locale.my_key_I)  # Unresolved attribute reference 'my_key_I for class 'MyLocale' 

You can still access your locale container dynamically if you want (e.g. when the key is known only at runtime).

key = f()  # returned 'my_key_1'

print(locale.get(key))  # My text

Other features?

• If your translation files don't follow the spec - SL10n will notify you and also try to fix it:

  • add all undefined keys
  • move all unexpected keys to the bottom of the file

• You can also create new translation files:

  from sl10n import SL10n, SLocale
  
  
  class MyLocale(SLocale):
      my_key_1: str
      my_key_2: str
  
  
  l10n = SL10n(MyLocale, 'lang')
  
  l10n.create_lang_file('de')  # copy the contents of default language file ('en') to a new file
  

• Define what filenames should be ignored:

  l10n = SL10n(MyLocale, 'lang', ignore_filenames=['config', 'tags'])
  

• Choose a different JSON parsing implementation (one of supported):

  import ujson
  
  l10n = SL10n(MyLocale, 'lang', json_impl=ujson)
  

• Apply some modifiers to your file (todo: make a docs explaining modifiers):

  {
      "my_key_1": "My text",
      "my_key_2": "Wrong text",
      "$redump": true  // redumps the file anyway
  }
  

  {
      "my_key_1": "My text",
      "my_key_2": "<not finished>",
      "$exclude": true  // excludes the file from parsing
  }
  

json_impl supports:

• json (builtin)
• simplejson (loads faster, dumps slower)
• ujson (loads and dumps much faster)

json_impl not supports (different interface):

• ijson
• orjson