124 lines
4.6 KiB
Markdown
124 lines
4.6 KiB
Markdown
# Gettext
|
|
|
|
[](https://hex.pm/packages/gettext)
|
|
[][docs-gettext]
|
|
|
|
|
|
Gettext is an **internationalization** (i18n) and **localization** (l10n) system commonly used for writing multilingual programs. Gettext is a standard for i18n in different communities, meaning there is a great set of tooling for developers and translators. This project is an implementation of the Gettext system in Elixir.
|
|
|
|
## Installation
|
|
|
|
Add `:gettext` to your list of dependencies in `mix.exs` (use `$ mix hex.info gettext` to find the latest version):
|
|
|
|
```elixir
|
|
defp deps do
|
|
[
|
|
{:gettext, ">= 0.0.0"}
|
|
]
|
|
end
|
|
```
|
|
|
|
Documentation for `Gettext` is [available on Hex][docs-gettext].
|
|
|
|
## Usage
|
|
|
|
To use Gettext, define a Gettext module:
|
|
|
|
```elixir
|
|
defmodule MyApp.Gettext do
|
|
use Gettext, otp_app: :my_app
|
|
end
|
|
```
|
|
|
|
and invoke the Gettext API, which consists of the `*gettext` macros:
|
|
|
|
```elixir
|
|
import MyApp.Gettext
|
|
|
|
# Simple message
|
|
gettext("Here is one string to translate")
|
|
|
|
# Plural message
|
|
number_of_apples = 4
|
|
ngettext("The apple is ripe", "The apples are ripe", number_of_apples)
|
|
|
|
# Domain-based message
|
|
dgettext("errors", "Here is an error message to translate")
|
|
```
|
|
|
|
Messages in Gettext are stored in Portable Object files (`.po`). Such files must be placed at `priv/gettext/LOCALE/LC_MESSAGES/DOMAIN.po`, where `LOCALE` is the locale and `DOMAIN` is the domain (the default domain is called `default`).
|
|
|
|
For example, the message to `pt_BR` of the first two `*gettext` calls in the snippet above must be placed in the `priv/gettext/pt_BR/LC_MESSAGES/default.po` file with contents:
|
|
|
|
```pot
|
|
msgid "Here is one string to translate"
|
|
msgstr "Aqui está um texto para traduzir"
|
|
|
|
msgid "Here is the string to translate"
|
|
msgid_plural "Here are the strings to translate"
|
|
msgstr[0] "Aqui está o texto para traduzir"
|
|
msgstr[1] "Aqui estão os textos para traduzir"
|
|
```
|
|
|
|
`.po` are text-based files and can be edited directly by translators. Some may even use existing tools for managing them, such as [Poedit][poedit] or [poeditor.com][poeditor.com].
|
|
|
|
Finally, because messages are based on strings, your source code does not lose readability as you still see literal strings, like `gettext("here is an example")`, instead of paths like `translate("some.path.convention")`.
|
|
|
|
Read the [documentation for the `Gettext` module][docs-gettext-module] for more information on locales, interpolation, pluralization, and other features.
|
|
|
|
## Workflow
|
|
|
|
Gettext is able to automatically extract messages from your source code, alleviating developers and translators from the repetitive and error-prone work of maintaining message files.
|
|
|
|
When extracted from source, Gettext places messages into `.pot` files, which are template files. You can then merge those templates files into message files for each specific locale your application is being currently translated to.
|
|
|
|
In other words, the typical workflow looks like this:
|
|
|
|
1. Add `gettext` calls to your source code. No need to touch message files
|
|
at this point as Gettext will return the given string if no message is
|
|
available:
|
|
|
|
```elixir
|
|
gettext("Welcome back!")
|
|
```
|
|
|
|
2. Once changes to the source are complete, automatically sync all existing entries to `.pot` (template files) in `priv/gettext` by running:
|
|
|
|
```bash
|
|
mix gettext.extract
|
|
```
|
|
|
|
3. You can then merge `.pot` files into locale-specific `.po` files:
|
|
|
|
```bash
|
|
# Merge .pot into all locales
|
|
mix gettext.merge priv/gettext
|
|
|
|
# Merge .pot into one specific locale
|
|
mix gettext.merge priv/gettext --locale en
|
|
```
|
|
|
|
It is also possible to both extract and merge messages in one step with `mix gettext.extract --merge`.
|
|
|
|
## License
|
|
|
|
Copyright 2015 Plataformatec
|
|
Copyright 2020 Dashbit
|
|
|
|
Licensed under the Apache License, Version 2.0 (the "License");
|
|
you may not use this file except in compliance with the License.
|
|
You may obtain a copy of the License at:
|
|
|
|
> <http://www.apache.org/licenses/LICENSE-2.0>
|
|
|
|
Unless required by applicable law or agreed to in writing, software
|
|
distributed under the License is distributed on an "AS IS" BASIS,
|
|
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
See the License for the specific language governing permissions and
|
|
limitations under the License.
|
|
|
|
[docs-gettext]: http://hexdocs.pm/gettext
|
|
[docs-gettext-module]: http://hexdocs.pm/gettext/Gettext.html
|
|
[poedit]: http://poedit.net/
|
|
[poeditor.com]: https://poeditor.com
|