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

The default approach to locale data management with gems such as i18n is flawed. If you use a key that does not exist, this will only blow up at runtime. Keys left over from removed code accumulate in the resource files and introduce unnecessary overhead on the translators. Translation files can quickly turn to disarray.

i18n-tasks improves this by analysing code statically, without running it. It scans calls such as I18n.t('some.key') and provides reports on key usage, missing, and unused keys. It can also pre-fill missing keys, including from Google Translate, and it can remove unused keys as well.

i18n-tasks can be used with any project using i18n (default in Rails), or similar, even if it isn't ruby.

Add to Gemfile:

gem 'i18n-tasks', '~> 0.6.3'

Copy default config file (optional):

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

Copy rspec test (optional):

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

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

$ i18n-tasks
Usage: i18n-tasks [command] [options]
    -v, --version      Print the version
    -h, --help         Display this help message.

Available commands:

  missing             show missing translations
  unused              show unused translations
  eq-base             show translations equal to base value
  find                show where the keys are used in the code
  data                show locale data
  translate-missing   translate missing keys with Google Translate
  add-missing         add missing keys to the locales
  normalize           normalize translation data: sort and move to the right files
  remove-unused       remove unused keys
  config              display i18n-tasks configuration
  xlsx-report         save missing and unused translations to an Excel file
  irb                 REPL session within i18n-tasks context
  gem-path            show path to the gem

See `<command> --help` for more information on a specific command.

Show tasks accept a format option, and all but find accept locales as arguments, e.g:

$ i18n-tasks data --help
Usage: i18n-tasks data [options]
    -l, --locales      Filter by locale(s), comma-separated list (en,fr) or all (default), or pass arguments without -l
    -f, --format       Output format: terminal-table, yaml, json, keys, inspect. Default: terminal-table.
    -h, --help         Display this help message.
$ i18n-tasks data -fkeys en es fr

You can add missing values, generated from the key (for base locale) or copied from the base locale (for other locales). To add missing values to the base locale only:

# most task accept locales as first argument. `base` and `all` are special
i18n-tasks add-missing base
# add-missing accepts a placeholder argument, with optional base_value interpolation
i18n-tasks add-missing -p 'PLEASE-TRANSLATE %{base_value}' fr

Translate missing values with Google Translate (more below on the API key).

i18n-tasks translate-missing
# accepts from and locales options:
i18n-tasks translate-missing --from base es fr

Sort the keys and write them to their respective files with i18n-tasks normalize. This always happens on i18n-tasks add-missing and i18n-tasks translate-missing.

i18n-tasks normalize

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

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

i18n-tasks unused
i18n-tasks remove-unused

These tasks will infer dynamic key usage such as t("category.\#{category.name}") by default. Pass -s or --strict to disable this feature.

Relative keys (t '.title') and plural keys (key.{one,many,other,...}) are fully supported. Scope argument is supported, but only when it is the first keyword argument (improvements welcome):

```ruby
# this is supported
t :invalid, scope: [:auth, :password], attempts: 5
# but not this
t :invalid, attempts: 5, scope: [:auth, :password]
```

Unused report will detect certain dynamic key forms and not report them, e.g.:

t 'category.' + category.key      # all 'category.*' keys are considered used
t "category.#{category.key}.name" # all 'category.*.name' keys are considered used

Translation data storage, key usage search, and other settings are compatible with Rails by default.

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

Install the default config file with:

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

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/i18n-tasks.yml
base_locale: en
locales: [es, fr] # This includes base_locale by default

The default data adapter supports YAML and JSON files.

# config/i18n-tasks.yml
data:
  # configure YAML / JSON serializer options
  # passed directly to load / dump / parse / serialize.
  yaml:
    write:
      # do not wrap lines at 80 characters (override default)
      line_width: -1

Use data options to work with locale data spread over multiple files.

data.read accepts a list of file globs to read from per-locale:

# config/i18n-tasks.yml
data:
  read:
    # read from namespaced files, e.g. simple_form.en.yml
    - 'config/locales/*.%{locale}.yml'
    # read from a gem (config is parsed with ERB first, then YAML)
    - "<%= %x[bundle show vagrant].chomp %>/templates/locales/%{locale}.yml"
    # default
    - 'config/locales/%{locale}.yml'

For writing to locale files i18n-tasks provides 2 options.

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 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 store data somewhere but in the filesystem, e.g. in the database or mongodb, you can implement a custom adapter. Implement a handful of methods, then set data.adapter to the class name; the rest of the data config is passed to the initializer.

# config/i18n-tasks.yml
data:
  # file_system is the default adapter, you can provide a custom class name here:
  adapter: file_system

Configure usage search in config/i18n-tasks.yml:

# config/i18n-tasks.yml
# i18n usage search in source
search:
  # search these directories (relative to your Rails.root directory, default: 'app/')
  paths:
    - 'app/'
    - 'vendor/'
  # paths for relative key resolution:
  relative_roots:
    # default:
    - app/views
    # add a custom one:
    - app/views-mobile
  # include only files matching this glob pattern (default: blank = include all files)
  include:
    - '*.rb'
    - '*.html.*'
    - '*.text.*'
  # explicitly exclude files (default: exclude common binary files)
  exclude:
    - '*.js'
  # you can override the default key regex pattern:
  pattern: "\\bt[( ]\\s*(:?\".+?\"|:?'.+?'|:\\w+)"
  # comments are ignored by default
  ignore_lines:
    - "^\\s*[#/](?!\\si18n-tasks-use)"

It is also possible to use a custom key usage scanner by setting search.scanner to a class name. See this basic pattern scanner for reference.

Add hints to static analysis with magic comment hints (lines starting with (#|/) i18n-tasks-use by default):

# i18n-tasks-use t('activerecord.models.user') # let i18n-tasks know the key is used
User.model_name.human

You can also explicitly ignore keys appearing in locale files:

# config/i18n-tasks.yml
# do not report these keys as unused
ignore_unused:
  - category.*.db_name

# do not report these keys as missing (both on blank value and no key)
ignore_missing:
  - devise.errors.unauthorized # ignore this key
  - pagination.views.*         # ignore the whole pattern
  # E.g to ignore all Rails number / currency keys:
  - 'number.{format, percentage.format, precision.format, human.format, currency.format}.{strip_insignificant_zeros,significant,delimiter}'
  - 'time.{pm,am}'

# do not report these keys when they have the same value as the base locale version
ignore_eq_base:
  all:
    - common.ok
  es,fr:
    - common.brand

# do not report these keys ever
ignore:
  - kaminari.*

i18n-tasks translate-missing requires a Google Translate API key, get it at Google API Console. Put the key in GOOGLE_TRANSLATE_API_KEY environment variable or in the config file.

# config/i18n-tasks.yml
translation:
  api_key: <Google Translate API key>

i18n-tasks irb starts an IRB session in i18n-tasks context. Type guide for more information.

You might want to test for missing and unused translations as part of your test suite. Install the spec file:

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

Export missing and unused data to XLSX:

$ i18n-tasks xlsx-report

While i18n-tasks does not provide an HTML version of the report, you can add one like this.

Tasks that come with the gem are defined in lib/i18n/tasks/commands.rb.

Add a custom task to the I18n::Tasks::Commands class and load the task in config/i18n-tasks.yml:

# lib/i18n/tasks/my_task.rb
I18n::Tasks::Commands.class_eval do
  cmd :my_task, desc: 'my task'
  def my_task(opts = {})
    puts i18n.data[opts[:arguments].try(:first) || base_locale]
  end
end

# config/i18n-tasks.yml
<% require 'i18n/tasks/my_task' %>

Run with:

$ i18n-tasks my-task