i18n-tasks

i18n-tasks [![Build Status][badge-ci]][ci]

i18n-tasks helps you find and manage missing and unused translations.

This gem analyses code statically for key usages, such as I18n.t('some.key'), in order to:

• Report keys that are missing or unused.
• Pre-fill missing keys, optionally from Google Translate or DeepL (Pro or Free).
• Remove unused keys.

Thus addressing the two main problems of [i18n gem][i18n-gem] design:

• Missing keys only blow up at runtime.
• Keys no longer in use may accumulate and introduce overhead, without you knowing it.

Table of Contents

• Quick Start
• Commands
  • Check health
  • Find usages
  • Add missing keys
  • Translate missing keys
  • Remove unused keys
  • Prune
  • Normalize
  • Move / rename / merge keys
  • Delete keys
  • Compose tasks
• Configuration
  • Locales
  • Storage & locale files
    • Pattern router
    • Conservative router
    • Isolating router
    • Key pattern syntax
    • Custom adapters
    • Rails credentials
  • Usage search
    • Prism-based scanner
  • Fine-tuning
  • Environment variables & dotenv
• Translation backends
  • Google Translate
  • DeepL
  • Yandex
  • OpenAI
  • watsonx
• Features & limitations
  • Relative keys
  • Plural keys
  • Reference keys
  • Dynamic keys
  • I18n.localize
  • t() keyword arguments
  • Unexpected normalization
• Advanced
  • Interactive console
  • CSV import / export
  • Add custom tasks
• Development

Quick Start

i18n-tasks can be used with any project using the ruby [i18n gem][i18n-gem] (default in Rails).

1. Add to your Gemfile:

   gem 'i18n-tasks', '~> 1.1.2', group: :development
   

2. Copy the default configuration file:

   $ cp $(bundle exec i18n-tasks gem-path)/templates/config/i18n-tasks.yml config/
   

3. Run your first health check:

   $ bundle exec i18n-tasks health
   

That's it. See Commands for the full list of tasks, or Configuration to tailor the setup to your project.

Optional: copy a test that checks for missing/unused translations on every CI run:

# RSpec
$ cp $(bundle exec i18n-tasks gem-path)/templates/rspec/i18n_spec.rb spec/

# Minitest
$ cp $(bundle exec i18n-tasks gem-path)/templates/minitest/i18n_test.rb test/

Commands

Run bundle exec i18n-tasks to get the list of all the tasks with short descriptions.

Check health

bundle exec i18n-tasks health checks if any keys are missing or not used, that interpolation variables are consistent across locales, and that all the locale files are normalized (auto-formatted):

$ bundle exec i18n-tasks health

Find usages

See where the keys are used with bundle exec i18n-tasks find:

$ bundle exec i18n-tasks find common.help
$ bundle exec i18n-tasks find 'auth.*'
$ bundle exec i18n-tasks find '{number,currency}.format.*'

Add missing keys

Add missing keys with placeholders (base value or humanized key):

$ bundle exec i18n-tasks add-missing

This and other tasks accept arguments:

$ bundle exec i18n-tasks add-missing -v 'TRME %{value}' fr

Pass --help for more information:

$ bundle exec i18n-tasks add-missing --help
Usage: i18n-tasks add-missing [options] [locale ...]
    -l, --locales  Comma-separated list of locale(s) to process. Default: all. Special: base.
    -f, --format   Output format: terminal-table, yaml, json, keys, inspect. Default: terminal-table.
    -v, --value    Value. Interpolates: %{value}, %{human_key}, %{value_or_human_key}, %{key}. Default: %{value_or_human_key}.
    -h, --help     Display this help message.

Translate missing keys

Translate missing keys using a backend service of your choice.

$ bundle exec i18n-tasks translate-missing

# accepts backend, from and locales options
$ bundle exec i18n-tasks translate-missing --from=base es fr --backend=google

Available backends:

• google – Google Translate
• deepl – DeepL
• yandex – Yandex
• openai – OpenAI
• watsonx – watsonx

Remove unused keys

$ bundle exec i18n-tasks unused
$ bundle exec i18n-tasks remove-unused

These tasks can infer dynamic keys such as t("category.\#{category.name}") if you set search.strict to false, or pass --no-strict on the command line.

If you want to keep the ordering from the original language file when using remove-unused, pass -k or --keep-order.

Prune keys not in base locale

Remove keys from non-base locales that are absent in the base locale:

$ i18n-tasks prune

Pass -k or --keep-order to preserve the original key ordering in the locale files.

Normalize

Sort the keys:

$ bundle exec i18n-tasks normalize

Sort the keys, and move them to the respective files as defined by config.write:

$ bundle exec i18n-tasks normalize -p

Move / rename / merge keys

bundle exec i18n-tasks mv <pattern> <target> is a versatile task to move or delete keys matching the given pattern.

All nodes (leafs or subtrees) matching <pattern> are merged together and moved to <target>.

Rename a node (leaf or subtree):

$ bundle exec i18n-tasks mv user account

Move a node:

$ bundle exec i18n-tasks mv user_alerts user.alerts

Move the children one level up:

$ bundle exec i18n-tasks mv 'alerts.{:}' '\1'

Merge-move multiple nodes:

$ bundle exec i18n-tasks mv '{user,profile}' account

Merge (non-leaf) nodes into parent:

$ bundle exec i18n-tasks mv '{pages}.{a,b}' '\1'

Delete keys

Delete the keys by using the rm task:

$ bundle exec i18n-tasks rm 'user.{old_profile,old_title}' another_key

Compose tasks

i18n-tasks also provides composable tasks for reading, writing and manipulating locale data. Examples below.

add-missing implemented with missing, tree-set-value and data-merge:

$ bundle exec i18n-tasks missing -f yaml fr | bundle exec i18n-tasks tree-set-value 'TRME %{value}' | bundle exec i18n-tasks data-merge

remove-unused implemented with unused and data-remove (sans the confirmation):

$ bundle exec i18n-tasks unused -f yaml | bundle exec i18n-tasks data-remove

Remove all keys from fr that do not exist in en. Do not change en:

$ bundle exec i18n-tasks missing -t diff -f yaml en | bundle exec i18n-tasks tree-mv en fr | bundle exec i18n-tasks data-remove

See the full list of tasks with bundle exec i18n-tasks --help.

Configuration

Configuration is read from config/i18n-tasks.yml or config/i18n-tasks.yml.erb. Inspect the configuration with bundle exec i18n-tasks config.

Install the [default config file][config] with:

$ cp $(bundle exec i18n-tasks gem-path)/templates/config/i18n-tasks.yml config/

Settings are compatible with Rails by default.

Locales

By default, base_locale is set to en and locales are inferred from the paths to data files. You can override these in the [config][config].

Storage & locale files

The default data adapter supports YAML and JSON files.

i18n-tasks can manage multiple translation files and read translations from other gems. To find out more see the data options in the [config][config]. NB: By default, only %{locale}.yml files are read, not namespace.%{locale}.yml. Make sure to check the config.

For writing to locale files i18n-tasks provides three routers.

Pattern router

Pattern router organizes keys based on a list of key patterns, as in the example below:

data:
  router: pattern_router
  # a list of {key pattern => file} routes, matched top to bottom
  write:
    # write models.* and views.* keys to the respective files
    - ["{models,views}.*", 'config/locales/\1.%{locale}.yml']
    # or, write every top-level key namespace to its own file
    - ["{:}.*", 'config/locales/\1.%{locale}.yml']
    # default, sugar for ['*', path]
    - "config/locales/%{locale}.yml"

Conservative router

Conservative router keeps the keys where they are found, or infers the path from base locale. If the key is completely new, conservative router will fall back to pattern router behaviour. Conservative router is the default router.

data:
  router: conservative_router
  write:
    - ["devise.*", "config/locales/devise.%{locale}.yml"]
    - "config/locales/%{locale}.yml"

If you want to have i18n-tasks reorganize your existing keys using data.write, either set the router to pattern_router as above, or run bundle exec i18n-tasks normalize -p (forcing the use of the pattern router for that run).

Isolating router

Isolating router assumes each YAML file is independent and can contain similar keys.

As a result, the translations are written to an alternate target file for each source file (only the %{locale} part is changed to match target locale). Thus, it is not necessary to specify any write configuration (in fact, it would be completely ignored).

This can be useful for example when using ViewComponent sidecars (ViewComponent assigns an implicit scope to each sidecar YAML file but i18n-tasks is not aware of that logic, resulting in collisions):

• app/components/movies_component.en.yml:

  en:
    title: Movies
  

• app/components/games_component.en.yml

  en:
    title: Games
  

This router has a limitation, though: it does not support detecting missing keys from code usage (since it is not aware of the implicit scope logic).

Key pattern syntax

A special syntax similar to file glob patterns is used throughout i18n-tasks to match translation keys:

syntax	description
*	matches everything
:	matches a single key
*:	matches part of a single key
{a, b.c}	match any in set, can use : and *, match is captured

Example of usage:

$ bundle exec i18n-tasks mv "{:}.contents.{*}_body" "\1.attributes.\2.body"

car.contents.name_body ⮕ car.attributes.name.body
car.contents.description_body ⮕ car.attributes.description.body
truck.contents.name_body ⮕ truck.attributes.name.body
truck.contents.description_body ⮕ truck.attributes.description.body

Custom adapters

If you store data somewhere but in the filesystem, e.g. in the database or mongodb, you can implement a custom adapter. If you have implemented a custom adapter please share it on [the wiki][wiki].

Rails credentials

If you use Rails credentials and want to load e.g. credentials for translation backends, convert your i18n-tasks.yml to i18n-tasks.yml.erb and add a `req