A command-line tool for automatically generating missing translations to ARB
files using Google Gemini or OpenAI ChatGPT by
LeanCode
Installation
$ dart pub global activate arb_translate
Configuration
arb_translate has been designed to seamlessly integrate with Flutter apps
using flutter_localizations for code generation from ARB files. Thanks to this
integration, the setup process for arb_translate can be completed in just a few
steps:
Generate your API key. You can create your Gemini key
here or your OpenAI key
here
Save your API token in the environment variable ARB_TRANSLATE_API_KEY or
add arb-translate-api-key: {your-api-key} to l10n.yaml in your project.
(Optional) Select model used for translation. To do it add
arb-translate-model to l10n.yaml or use command argument --model. The default model is
gemini-2.5-flash. For all available models see arb_translate --help.
(Optional) Add context of your application
arb-translate-context: {your-app-context} eg. "sporting goods store app"
All other required parameters match flutter_localizations parameters and will
be read from l10n.yaml file. You can override them using command arguments if
necessary. See arb_translate --help for more information.
Configuration without l10n.yaml
If you project doesn't include l10n.yaml configuration you have to provide
configuration using environment variables and command arguments. You also have
to provide:
--arb-dir The directory where the template and translated ARB files are
located
--template-arb-file The template ARB file that will be used as the basis
for translation
See arb_translate --help for more information.
Custom model configuration
You can use arb_translate with any model with an OpenAI-compatible API. To configure a custom model:
Add arb-translate-custom-model: {your-model-name} to l10n.yaml or specify
as command argument custom-model: {your-model-name}
Add arb-translate-custom-model-provider-base-url: {your-model-url} to
l10n.yaml or specify as command argument: --custom-model-provider-base-url: {your-model-url}
(Optional) Set target batch size appropriately to model token count limits by
adding arb-translate-batch-size: {size} to your l10n.yaml or specify as
command argument batch-size: {size}. Batch size is the number of characters
of ARB messages in a single batch and does not include the prompt or app
context.
Usage
To generate translations, simply call arb_translate. All messages included in
the template ARB file but missing from other files will be translated. To add a
new locale, simply add an empty ARB file.
$ arb_translate
Or without l10n.yaml file
$ arb_translate --arb-dir...
Read more
If you want to know how we made this tool and what challenges we had,
read the story.
