i18n-ai-translate

Leverage ChatGPT or Google Gemini for seamless translation of application localization files across any language. Supports templated strings, and ensures consistent formatting. Requires i18next-style JSON files.

Three prompts are chained to ensure each translation is well-formed.

1. The translation prompt attempts a translation
2. The translation verification prompt uses a separate context to verify the translation
3. The styling verification prompt uses yet another context to verify the translation's formatting is consistent with the source

History is retained between calls to ensure consistency when translating the entire file.

Usage

Quick-start

Running directly

git clone [email protected]:taahamahdi/i18n-ai-translate.git
cd i18n-ai-translate
yarn
cp /home/en.json jsons/

# Generate French translations
npm run i18n-ai-translate -- translate -i en.json -o fr.json --engine chatgpt --model gpt-4o --api-key <openai_key>

Running as a script in your own project

yarn add i18n-ai-translate

# Generate French translations
npx i18n-ai-translate translate -i en.json -o fr.json --engine gemini --model gemini-pro --api-key <gemini_key>

# Or, assuming you already have other translations in the current directory
npx i18n-ai-translate diff --before en-before.json --after en.json --input-language English --engine chatgpt --model gpt-4 --api-key <openai_key>

Running as a library

import { translate } from "i18n-ai-translate";
...
const englishJSON = {
  "welcomeMessage": "Welcome, {{name}}!",
  "messages": {
    "notifications_one": "You have one notification",
    "notifications_other": "You have {{count}} notifications",
    "delete": "Would you like to delete the \"{{name}}\" category?"
  }
};

const frenchTranslation = await translate({
  inputJSON: englishJSON,
  inputLanguage: "English",
  outputLanguage: "French",
  ...
});

console.log(frenchTranslation);

{
  "welcomeMessage": "Bienvenue, {{name}} !",
  "messages": {
    "notifications_one": "Vous avez une notification",
    "notifications_other": "Vous avez {{count}} notifications",
    "delete": "Voulez-vous supprimer la catégorie « {{name}} » ?"
  }
}

GitHub Actions

Incorporate it into your CI with a GitHub Action to auto-translate keys for every pull request: action.yml

Script

Use i18n-ai-translate translate to convert a local i18n JSON file to any language. Relative paths begin from the jsons/ directory.

Use i18n-ai-translate diff to find the differences between two versions of a source language file, and apply them to all language files in the same directory.

Create a .env file with an entry for your API key, or pass the --api-key flag.

• GEMINI_API_KEY=<your Gemini API key>
• OPENAI_API_KEY=<your OpenAI API key>

Usage: i18n-ai-translate [options] [command]

Use ChatGPT or Gemini to translate your i18n JSON to any language

Options:
  -V, --version        output the version number
  -h, --help           display help for command

Commands:
  translate [options]
  diff [options]
  help [command]       display help for command

Usage: i18n-ai-translate translate [options]

Options:
  -i, --input <input>                        Source i18n file, in the jsons/ directory if a relative path is given
  -o, --output <output>                      Output i18n file, in the jsons/ directory if a relative path is given
  -e, --engine <engine>                      Engine to use (chatgpt or gemini)
  -m, --model <model>                        Model to use (e.g. gpt-4o, gpt-4, gpt-3.5-turbo, gemini-pro)
  -r, --rate-limit-ms <rateLimitMs>          How many milliseconds between requests (defaults to 1s for Gemini, 120ms (at 500RPM) for ChatGPT)
  -f, --force-language-name <language name>  Force language name
  -A, --all-languages                        Translate to all supported languages
  -l, --languages [language codes...]        Pass a list of languages to translate to
  -p, --templated-string-prefix <prefix>     Prefix for templated strings (default: "{{")
  -s, --templated-string-suffix <suffix>     Suffix for templated strings (default: "}}")
  -k, --api-key <API key>                    API key
  --ensure-changed-translation               Each generated translation key must differ from the input (for keys longer than 4) (default: false)
  -n, --batch-size <batchSize>               How many keys to process at a time (default: "32")
  --verbose                                  Print logs about progress (default: false)
  -h, --help                                 display help for command

Usage: i18n-ai-translate diff [options]

Options:
  -b, --before <fileBefore>               Source i18n file before changes, in the jsons/ directory if a relative path is given
  -a, --after <fileAfter>                 Source i18n file after changes, in the jsons/ directory if a relative path is given
  -l, --input-language <inputLanguage>    The full input language name
  -e, --engine <engine>                   Engine to use (chatgpt or gemini)
  -m, --model <model>                     Model to use (e.g. gpt-4o, gpt-4-turbo, gpt-4, gpt-3.5-turbo, gemini-pro)
  -r, --rate-limit-ms <rateLimitMs>       How many milliseconds between requests (defaults to 1s for Gemini, 120ms (at 500RPM) for
                                          ChatGPT)
  -k, --api-key <API key>                 API key
  --ensure-changed-translation            Each generated translation key must differ from the input (for keys longer than 4)
                                          (default: false)
  -p, --templated-string-prefix <prefix>  Prefix for templated strings (default: "{{")
  -s, --templated-string-suffix <suffix>  Suffix for templated strings (default: "}}")
  -n, --batch-size <batchSize>            How many keys to process at a time (default: "32")
  --verbose                               Print logs about progress (default: false)
  -h, --help                              display help for command

Example usage

npx i18n-ai-translate translate -i en.json -o fr.json

• Translate the en.json file in jsons/ to French, and save the output in fr.json

npx i18n-ai-translate translate -i en.json -l es de nl --engine gemini

• Translate the en.json file in jsons/ to Spanish, German, and Dutch, and save each file in jsons/, using Google Gemini

npx i18n-ai-translate diff -b en.json -a en-after.json -l English --verbose

• Translate the keys that have changed between en.json and en-after.json for all files in the en.json directory, with logging enabled

npx i18n-ai-translate translate -i en.json -A --engine chatgpt --model gpt-4-turbo --api-key <my_key> --rate-limit-ms 150 -n 64

• Translate the en.json file in jsons/ to 200+ languages, save each file in jsons/, using the GPT-4 Turbo model of ChatGPT, with the given key, a rate limit of 150ms between requests, and 64 keys sent in each batch

As a library

Alternatively, import this project and use it to convert JSONs on-the-fly with translate(), or use translateDiff() to fetch updates to modified keys when your source i18n file has changed.

import { translate, translateDiff } from "i18n-ai-translate";

...

const translation = await translate({
    engine, // ChatGPT or Gemini
    model, // The model to use with the engine (e.g. gpt-4o, gpt-4, gpt-3.5-turbo, gemini-pro)
    chatParams, // Additional configuration to pass to the model
    rateLimitMs, // How many milliseconds between requests
    apiKey, // Gemini API key
    inputJSON, // JSON to translate
    inputLanguage, // Language of inputJSON
    outputLanguage, // Targeted language (e.g. French, Spanish, etc.)
    templatedStringPrefix, // The start of inline variables; defaults to "{{"
    templatedStringSuffix, // The end of inline variables; defaults to "}}"
    verbose, // Print status of conversion to stdout/stderr
    ensureChangedTranslation, // Every key longer than 4 characters must be different than the input
    batchSize, // How many keys to process at a time
});

const translations = await translateDiff({
    engine, // ChatGPT or Gemini
    model, // The model to use with the engine (e.g. gpt-4o, gpt-4, gpt-3.5-turbo, gemini-pro)
    chatParams, // Additional configuration to pass to the model
    rateLimitMs, // How many milliseconds between requests
    apiKey, // Gemini API key
    inputLanguage, // Language of inputJSONBefore/After
    inputJSONBefore, // The source translation before a change
    inputJSONAfter, // The source translation after a change
    inputLanguage, // Language of inputJSONBefore/After
    toUpdateJSONs, // An object of language codes to their translations
    templatedStringPrefix, // The start of inline variables; defaults to "{{"
    templatedStringSuffix, // The end of inline variables; defaults to "}}"
    ensureChangedTranslation, // Every key longer than 4 characters must be different than the input
    verbose, // Print status of conversion to stdout/stderr
    batchSize, // How many keys to process at a time
});

Translation prompt

Batches of the i18n input are passed in. Each call is checked to ensure no keys are lost, all templated strings are retained, and no translations were skipped.

You are a professional translator.

Translate each line from ${inputLanguage} to ${outputLanguage}.

Return translations in the same text formatting.

Maintain case sensitivity and whitespacing.

Output only the translations.

All lines should start and end with an ASCII quotation mark (").

${input}

Translation verification prompt

The output of the translation is sent back to ensure the model is okay with the translation. If this fails, the translation is re-generated.

Given a translation from ${inputLanguage} to ${outputLanguage} in CSV form, reply with NAK if _any_ of the translations are poorly translated.

Otherwise, reply with ACK.

Only reply with ACK/NAK.

Styling verification prompt

Formatting from the input should be retained where possible. If punctuation, capitalization, or whitespaces differ between the source and the translation, the translation is re-generated.

Given text from ${inputLanguage} to ${outputLanguage} in CSV form, reply with NAK if _any_ of the translations do not match the formatting of the original.

Check for differing capitalization, punctuation, or whitespaces.

Otherwise, reply with ACK.

Only reply with ACK/NAK.