doti18n 0.9.2

Python library for loading localizations with dot access and pluralization.

Modern, type-safe i18n / l10n library for Python.
The alternative to standart i18n libraries with dot-notation, ICU Message Format, and IDE autocompletion.

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Overview

doti18n allows you to replace string-based dictionary lookups with intuitive object navigation. Instead of locales['en']['messages']['error'], just write locales["en"].messages.error.

It focuses on Developer Experience (DX) by providing a CLI tool to generate .pyi stubs. This enables IDE autocompletion and allows static type checkers (mypy, pyright) to catch missing keys at build time.

Key Features

• Dot-Notation: Access nested keys via attributes (data.key) and lists via indices (items[0]).
• Type Safety: Generate stubs to get full IDE support and catch typos instantly.
• Advanced ICUMF: Full support for ICU Message Format including nested select, plural, and custom formatters.
• Pluralization: Robust support powered by Babel.
• Format Agnostic: Supports YAML, JSON, XML, TOML out of the box.
• Safety Modes:
  • Strict: Raises exceptions for missing keys (good for dev/test).
  • Non-strict: Returns a safe wrapper and logs warnings (good for production).
• Fallback: Automatically falls back to the default locale if a key is missing.
• Macros: Define reusable snippets for common patterns (e.g., reusable gender-select ICU snippets).
• Powerful CLI: Generate stubs, lint for missing keys, and run a web-based translation studio.

Installation

Requires Python 3.11+

pip install doti18n

If you use YAML files:

pip install doti18n[yaml]

Usage

1. Create a localization file (locales/en.yaml):

__macros__: # Define a section with macros
    gender: {gender, select, male {He} female {She} other {They}}

greeting: "Hello {}!"
farewell: "Goodbye $name!"

# Using macros
user_action: "@gender uploaded a new photo."
user_status: "@gender is currently online."

items:
    - name: "Item 1"
    - name: "Item 2"

# Basic key-based pluralization
notifications:
    one: "You have {count} new notification."
    other: "You have {count} new notifications."

# Complex ICU Message Format (Nesting + Select + Plural)
loot_msg: |
  {hero} found {type, select,
      weapon {{count, plural, one {a legendary sword} other {# rusty swords}}}
      potion {{count, plural, one {a healing potion} other {# healing potions}}}
      other {{count} items}
  } in the chest.

2. Access it in Python:

from doti18n import LocaleData

# Initialize (loads and caches data)
i18n = LocaleData("locales")
en = i18n["en"]

# 1. Standard formatting (Python-style)
print(en.greeting("John"))              # Output: Hello John!

# 2. Variable formatting (Shell-style)
print(en.farewell(name="Alice"))        # Output: Goodbye Alice!

# 3. Raw strings and graceful handling
print(en.farewell)                      # Output: Goodbye $name! (Raw string)
print(en.farewell())                    # Output: Goodbye ! (Missing var handled)

# 4. Using strings with macros
print(en.user_action(gender="male"))    # Output: He uploaded a new photo.
print(en.user_status(gender="female"))  # Output: She is currently online.

# 5. List access
print(en.items[0].name)                 # Output: Item 1

# 6. Basic Pluralization
print(en.notifications(1))              # Output: You have 1 new notification.

# 7. Advanced ICUMF Logic
# "weapon" branch -> "one" sub-branch
print(en.loot_msg(hero="Arthur", type="weapon", count=1))
# Output: Arthur found a legendary sword in the chest.

# "potion" branch -> "other" sub-branch
print(en.loot_msg(hero="Merlin", type="potion", count=5))
# Output: Merlin found 5 healing potions in the chest.

CLI

Stub Generation / Type Safety

doti18n comes with a CLI to generate type stubs (.pyi).

Why use it?

1. Autocompletion: Your IDE will suggest available keys as you type.
2. Validation: Static analysis tools will flag errors if you try to access a key that doesn't exist.
3. Deep ICUMF Introspection: The generator parses complex ICUMF strings (like the loot_msg example above) and creates precise function signatures.
   • Example: For loot_msg, it generates: def loot_msg(self, *, hero: str, type: str, count: int) -> str.
   • Your IDE will tell you exactly which arguments are required, even for deeply nested logic.

Commands:

# Generate stubs for all files in 'locales/' (default lang: en)
python -m doti18n stub locales/

# Generate stubs with a specific default language
python -m doti18n stub locales/ -lang fr

# Clean up generated stubs
python -m doti18n stub --clean

Note: Run this inside your virtual environment to ensure stubs are generated for the installed package.

Lint

Scan your translation files for missing keys, type mismatches, and structural issues across locales.

# Lint all locales against the default language (en)
doti18n lint locales/

# Lint against a specific source language
doti18n lint locales/ -lang fr

Studio

A web-based translation editor that runs locally. It lets you browse, edit, and save translations in real time from the browser. Multiple users can work simultaneously — edits are synced via WebSocket.

Studio requires extra dependencies:

pip install doti18n[studio]

First, create a user:

doti18n studio add-user admin mypassword

Then start the server:

doti18n studio run locales/

Open http://127.0.0.1:5000, log in, and you'll see all your locales and keys ready to edit.

Project Status

Alpha Stage: The API is stable but may evolve before the 1.0.0 release. Feedback and feature requests are highly appreciated!

Documentation

Documentation is available at darkj3suss.github.io/doti18n.

License

MIT License. See LICENSE for details.

Contact

• Issues: GitHub Issues
• Direct: Telegram