LocaleSync: i18n Data Manager

A clean, sidebar-based control panel for managing your i18n translation files. Add new keys to every language file at once, create new language files in a click, spot missing translations at a glance, and translate them with a single click using GitHub Copilot or any other VS Code language model, all without leaving VS Code.

Features

• Sidebar control panel - a dedicated activity-bar view with everything you need.
• Configure once - point it at the folder where your *.json translation files live (per-workspace setting).
• One key, all languages - adding a new translation key writes to every language file in sync.
• Inline editing - click any key to expand and edit values for every language right in the sidebar. Saves on blur or Ctrl/Cmd+Enter.
• AI translation (optional) - one-click translate via the VS Code Language Model API. Works with GitHub Copilot or any other installed LM provider. Translate a single language or all of them from a chosen source.
• Add languages in a click - new language files come pre-populated with all existing keys (empty, ready to translate).
• Sync check - find keys missing in some files and fill them in (with empty values) in one click.
• Smart search - filter by key name or by the value text in any language.
• Incomplete-only filter - instantly see what still needs translating.
• Nested keys supported - dot-notation in the UI (common.buttons.submit), nested JSON on disk.
• Theme-aware - uses VS Code's theme variables, so it matches whatever you've got.

📸 Preview

Getting started

1. Install the extension from the VS Code Marketplace.
2. Open a workspace that contains your translation files.
3. Click the 🌐 i18n Data Manager icon in the activity bar.
4. Click Choose Translations Folder and pick the folder containing your en.json, fr.json, etc.
5. Done, start adding keys and languages from the sidebar.

AI translation

If you have GitHub Copilot (or any other VS Code language model provider) installed and signed in, expand any translation key and you'll see two new actions:

• ✨ next to each language translate just that language. You'll be prompted to pick which other language to translate from (the source). The model receives the source value and writes the translation directly into the target language's file.
• ✨ Translate all in the key's actions row translate the same key into every other language at once. You pick the source language; if any target already has a value, you're asked whether to overwrite or only fill empties.

Notes:

• The extension uses the VS Code Language Model API. Your prompts go to whichever provider you have installed, Anthropic isn't called directly, no API key is shipped, and the user (you) authorizes usage on first run.
• The buttons only appear when a model is reachable. If you don't have an LM provider, the extension works exactly as before, no buttons, no errors.
• Placeholders ({name}, {{count}}, %s, %d, ICU plurals, HTML tags) are preserved by the prompt. Always review machine translations before shipping, especially for shorter keys where context can be ambiguous.
• You can disable the AI buttons entirely via the LocaleSynci18n.aiTranslate.enabled setting, even when a model is available.

Expected file layout

The extension expects one JSON file per language inside the configured folder. The filename (without .json) is taken as the language code:

locales/
├── en.json
├── fr.json
├── es.json
└── de-DE.json

Both flat ({ "hello": "Hi" }) and nested ({ "common": { "hello": "Hi" } }) JSON are supported. Nested files are flattened to dot-notation in the UI and re-nested on write, preserving your existing structure.

Keyboard shortcuts (inside the sidebar)

Settings

These settings are written to your workspace settings, so each project can have its own config.

Commands

Available from the Command Palette (Ctrl/Cmd+Shift+P):

• i18n Data Manager: Configure Translations Folder
• i18n Data Manager: Refresh

Build from source

git clone https://github.com/mmlTools/localesync-i18n.git
cd localesync-i18n
npm install
npm run compile

Then open the folder in VS Code and press F5 to launch the Extension Development Host.

See CONTRIBUTING.md for the full dev workflow.

Package & publish

npm install -g @vscode/vsce
npm run package        # → localesync-i18n-1.1.0.vsix
npm run publish        # publishes to the marketplace (requires `vsce login`)

Requirements

• VS Code 1.90.0 or later (required for the Language Model API).
• For AI translation: any installed VS Code language model provider for example, GitHub Copilot. The rest of the extension has no extra dependencies.

Known limitations

• Only .json files are supported (not .yaml, .po, .properties, etc.).
• Pluralization rules (CLDR plural categories) aren't handled, values are treated as plain strings.
• Comments in JSON files aren't preserved (standard JSON.parse / JSON.stringify).
• AI translation quality depends on the underlying language model and the amount of context in the source string. Always review output for short or ambiguous keys.

Changelog

See CHANGELOG.md for the full version history.

License

MIT © StreamRsc.com