ngx-i18n-extract-regex-cli

Extract Transloco and ngx-translate keys from Angular templates and TypeScript files.

Installation

Node.js 22.12 or newer is required to run the published CLI.

Install the CLI globally:

npm install --global ngx-i18n-extract-regex-cli

You can also run it without a global installation:

npx ngx-i18n-extract-regex-cli --help

Usage

From the root of an Angular project, run:

ngx-i18n-extract-regex-cli extract --library transloco

By default, the CLI:

• scans src/app/**/*.ts and src/app/**/*.html;
• reads language files matching src/assets/i18n/*.json;
• retains values for translation keys that already exist;
• adds missing values as ███; and
• removes unused keys and writes the remaining keys in alphabetical order.

Use --dry-run to inspect the number of discovered keys without changing language files:

ngx-i18n-extract-regex-cli extract --library ngx-translate --dry-run

Custom paths

Paths are resolved relative to --cwd. Quote glob patterns so that the CLI, rather than your shell, expands them.

ngx-i18n-extract-regex-cli extract \
  --library transloco \
  --cwd projects/example/src \
  --source 'app/**/*.ts' 'app/**/*.html' \
  --langs 'assets/i18n/*.json' \
  --default-value 'TODO'

Supported expressions

The extractor recognizes common static string usages, including:

{{ 'home.title' | transloco }} {{ 'home.title' | translate }}

transloco.translate('home.title');
translate.instant('home.title');
_('home.title');

Dynamic keys cannot be discovered reliably and should be added to your language files by another mechanism.

Options

Option	Values	Default	Description
--library	transloco, ngx-translate	transloco	Select the i18n library syntax to scan for.
--cwd	path	src	Set the base directory for source and language globs.
--source	one or more globs	app/**/*.ts app/**/*.html	Select source files to scan.
--langs	one or more globs	assets/i18n/*.json	Select language JSON files to update.
--default-value	string	███	Set the value assigned to newly discovered keys.
--dry-run	flag	disabled	Scan without writing language files.
--encoding	Node.js buffer encoding	utf-8	Set the source and output file encoding.

Run ngx-i18n-extract-regex-cli extract --help for the complete command help.

Development

Development uses the Node.js version declared in .nvmrc and the Bun version declared in package.json:

nvm install
nvm use
bun install
bun run lint
bun run build
bun run test:coverage

See CONTRIBUTING.md for contribution guidelines.

License

Copyright © 2024–2026 Dominik Hladík

Licensed under the MIT License.