:globe_with_meridians: Efficient translation module for Angular

Table of contents

• :package: Installation
• :gem: Key benefits
• :rocket: Quick start
• :wrench: Language configuration
  • Default language
  • Supported languages
  • Language guards
  • Language source
  • Language change handler
• License

:package: Installation

Using NPM:

npm i @ngry/translate

Using Yarn:

yarn add @ngry/translate

:arrow_up: Table of contents

:gem: Key benefits

Flexible language configuration: define a default language, a list of supported languages; provide a custom language source; control the language resolution using guards; control the language transition process using a language change handler.

Component-scoped translations: just like styles, translation isolation makes components more standalone and reusable and eliminates long translation keys.

Performance: Angular compiler applies all the same optimizations to translations as it does to the normal code - tree shaking, code splitting and lazy loading.

:rocket: Quick start

Provide a language configuration using LanguageModule.

If you're using standalone components, declare LanguageModule in bootstrapApplication's providers:

import { bootstrapApplication } from '@angular/platform-browser';
import { LanguageModule } from '@ngry/translate';

bootstrapApplication(AppComponent, {
  providers: [
    LanguageModule({
      default: 'en',
    }),
  ],
});

If you still using NgModules, declare LanguageModule in providers (yes, providers) of your app module:

import { NgModule } from '@angular/core';
import { LanguageModule } from '@ngry/translate';

@NgModule({
  providers: [
    LanguageModule({
      default: 'en',
    }),
  ],
})
export class AppModule {}

Add component's translations in a separate .json or .ts file next to the rest of its files:

📁 user-menu
   📄 user-menu.component.html
   📄 user-menu.component.json // component's translations
   📄 user-menu.component.scss
   📄 user-menu.component.ts
   📄 user-menu.component.spec.ts

Add translations for each supported language for this component:

user-menu.component.json

{
  "en": {
    "account": "Account",
    "settings": "Settings",
    "sign-out": "Sing out",
    "sign-out-confirmation": "Do you want to sign out?"
  },
  "uk": {
    "account": "Обліковий запис",
    "settings": "Налаштування",
    "sign-out": "Вихід",
    "sign-out-confirmation": "Ви справді хочете вийти?"
  }
}

Import translations just like any other file and provide them to component's viewProviders using TranslateProvider factory:

user-menu.component.ts

import { TranslatePipe, TranslateProvider } from '@ngry/translate';
import TEXT_DATA from './user-menu.component.json';

@Component({
  selector: 'app-user-menu',
  templateUrl: './user-menu.component.html',
  styleUrls: ['./user-menu.component.scss'],
  imports: [TranslatePipe],
  viewProviders: [TranslateProvider(TEXT_DATA)],
})
export class UserMenuComponent {}

:information_source: Hint

In order to import .json files, make sure you have these options enabled in tsconfig.json:

"resolveJsonModule": true,
"allowSyntheticDefaultImports": true,

Access phrase by key in component's template using translate pipe (declarative approach):

user-menu.component.html

<app-menu>
  <app-menu-item>{{'account' | translate}}</app-menu-item>
  <app-menu-item>{{'settings' | translate}}</app-menu-item>
  <app-menu-item>{{'sign-out' | translate}}</app-menu-item>
</app-menu>

Access phrase by key in component's code using useTranslate hook (imperative approach):

user-menu.component.ts

import {
  TranslatePipe,
  TranslateProvider,
  useTranslate,
} from '@ngry/translate';
import TEXT_DATA from './user-menu.component.json';

@Component({
  selector: 'app-user-menu',
  templateUrl: './user-menu.component.html',
  styleUrls: ['./user-menu.component.scss'],
  imports: [TranslatePipe],
  viewProviders: [TranslateProvider(TEXT_DATA)],
})
export class UserMenuComponent {
  private translate = useTranslate();

  signOut() {
    this.dialog
      .confirm(this.translate('sign-out-confirmation'))
      .pipe(
        filter(Boolean),
        tap(() => this.session.signOut()),
      )
      .subscribe();
  }
}

:arrow_up: Table of contents

:wrench: Language configuration

The module provides a flexible language configuration allowing to override behavior.

Default language

Used as a fallback when the LanguageSource provides a non-supported one.

import { bootstrapApplication } from '@angular/platform-browser';
import { LanguageModule } from '@ngry/translate';

bootstrapApplication(AppComponent, {
  providers: [
    LanguageModule({
      default: 'en',
    }),
  ],
});

:information_source: Hint

It's recommented to use ISO 639-1 format for language codes.

Examples: "en", "uk", "pl", "zh", "it", "de" etc.

:arrow_up: Table of contents | Language configuration

Supported languages

Used to guarantee only supported language can be used.

import { bootstrapApplication } from '@angular/platform-browser';
import { LanguageModule } from '@ngry/translate';

bootstrapApplication(AppComponent, {
  providers: [
    LanguageModule({
      default: 'en',
      supported: ['en', 'fr', 'de', 'uk'],
    }),
  ],
});

:arrow_up: Table of contents | Language configuration

Language guards

Language guards resolve a LanguageSource's language into a supported format and value.

import { bootstrapApplication } from '@angular/platform-browser';
import { LanguageModule, LanguageMappingGuard } from '@ngry/translate';

bootstrapApplication(AppComponent, {
  providers: [
    LanguageModule({
      default: 'en',
      supported: ['en', 'fr', 'de', 'uk'],
      guards: [
        LanguageMappingGuard({
          en: [/^en/i],
          fr: [/^fr/i],
          de: [/^de/i],
          ua: [/^ua/i, /^ru/i, /^be/i],
        }),
      ],
    }),
  ],
});

:arrow_up: Table of contents | Language configuration

Language source

A language source is an entity which

• encapsulates the source of the current language,
• pushes updates when the current language has been changed within the source.

import { bootstrapApplication } from '@angular/platform-browser';
import { LanguageModule, BrowserLanguageSource } from '@ngry/translate';

bootstrapApplication(AppComponent, {
  providers: [
    LanguageModule({
      default: 'en',
      supported: ['uk', 'en', 'fr', 'de'],
      source: BrowserLanguageSource(),
    }),
  ],
});

:arrow_up: Table of contents | Language configuration

Language change handler

A language change handler is an entity that gives you control over the decision when and how to apply the new language.

On one side, the language source only notifies about language change. On the other side, the language change handler makes a final decision about 2 things:

• whether to apply the new language;
• what the new language will be applied in the end.

import { bootstrapApplication } from '@angular/platform-browser';
import { LanguageModule, BrowserLanguageSource } from '@ngry/translate';
import { ConfirmLanguageChangeHandler } from './app/configuration/language/confirm-language-change-handler';

bootstrapApplication(AppComponent, {
  providers: [
    LanguageModule({
      default: 'en',
      supported: ['uk', 'en', 'fr', 'de'],
      source: BrowserLanguageSource(),
      change: ConfirmLanguageChangeHandler(),
    }),
  ],
});

:arrow_up: Table of contents | Language configuration

License

MIT