@larscom/ngx-translate-module-loader

@larscom/ngx-translate-module-loader

Highly configurable and flexible translations loader for @ngx-translate/core. Fetch multiple translations (http only)

Each translation file has it's own namespace out of the box so the key/value pairs do not conflict with each other. Namespacing can be disabled or you can provide your own value.

Demo

You can play arround on StackBlitz: https://stackblitz.com/edit/ngx-translate-module-loader

Dependencies

@larscom/ngx-translate-module-loader depends on @ngx-translate/core and Angular.

Installation

npm i --save @larscom/ngx-translate-module-loader

Usage

1. create an exported moduleHttpLoaderFactory function

import { NgModule } from '@angular/core';
import { BrowserModule } from '@angular/platform-browser';
import { HttpClientModule, HttpClient } from '@angular/common/http';
import { TranslateModule, TranslateLoader } from '@ngx-translate/core';
import { FileType, ModuleTranslateLoader, IModuleTranslationOptions } from '@larscom/ngx-translate-module-loader';
import { AppComponent } from './app';

export function moduleHttpLoaderFactory(http: HttpClient) {
  const fileType = FileType.JSON;
  const baseTranslateUrl = './assets/i18n';

  const options: IModuleTranslationOptions = {
    modules: [
      // final url: ./assets/i18n/en.json
      { baseTranslateUrl, fileType },
      // final url: ./assets/i18n/feature1/en.json
      { moduleName: 'feature1', baseTranslateUrl, fileType },
      // final url: ./assets/i18n/feature2/en.json
      { moduleName: 'feature2', baseTranslateUrl, fileType }
    ]
  };
  return new ModuleTranslateLoader(http, options);
}

@NgModule({
  imports: [
    BrowserModule,
    HttpClientModule,
    TranslateModule.forRoot({
      loader: {
        provide: TranslateLoader,
        useFactory: moduleHttpLoaderFactory,
        deps: [HttpClient]
      }
    })
  ],
  bootstrap: [AppComponent]
})
export class AppModule {}

Namespacing

By default, each translation file gets it's own namespace based on the moduleName, what does it mean?

For example with these options:

export function moduleHttpLoaderFactory(http: HttpClient) {
  const fileType = FileType.JSON;
  const baseTranslateUrl = './assets/i18n';

  const options: IModuleTranslationOptions = {
    modules: [
      // no moduleName/namespace
      { baseTranslateUrl, fileType },
      // nameSpace: FEATURE1
      { moduleName: 'feature1', baseTranslateUrl, fileType },
      // nameSpace: FEATURE2
      { moduleName: 'feature2', baseTranslateUrl, fileType }
    ]
  };
  return new ModuleTranslateLoader(http, options);
}

Lets say each module in the above example resolves to the following translation:

{
  "KEY: "VALUE"
}

The final result would then be:

{
   "KEY: "VALUE",
   "FEATURE1" : {
     "KEY: "VALUE"
   },
    "FEATURE2" : {
     "KEY: "VALUE"
   }
}

If you don't need upper case keys, set nameSpaceUppercase to false in the options because it's upper case by default. If you don't want to enable namespaces at all, set enableNamespacing to false.

You can override the default name space by setting the nameSpace property in the options.

Configuration

export interface IModuleTranslationOptions {
  /**
   * The translation module configurations
   */
  modules: IModuleTranslation[];
  /**
   * Each module gets its own namespace so it doesn't conflict with other modules
   */
  enableNamespacing?: boolean;
  /**
   * Create namespaces in Uppercase if namespacing is enabled
   */
  nameSpaceUppercase?: boolean;
  /**
   * Perform a deepmerge when merging translation files
   */
  deepMerge?: boolean;
  /**
   * Function that gets executed if an error occurred while retrieving a translation file
   * @param error the error that occurred
   * @param path the path to the location file
   */
  translateError?: (error: any, path: string) => void;
  /**
   * Custom translate merge function after retrieving all translation files
   * @param translations the resolved translation files
   */
  translateMerger?: (translations: Translation[]) => Translation;
  /**
   * Custom module path template for fetching translations
   * @example
   * '{baseTranslateUrl}/{moduleName}/{language}{fileType}'
   */
  modulePathTemplate?: string;
  /**
   * Custom path template for fetching translations
   * @example
   * '{baseTranslateUrl}/{language}{fileType}'
   */
  pathTemplate?: string;
}

export interface IModuleTranslation {
  /**
   * The module name
   *
   * For example: shared
   * @description omit moduleName if you have a translate file at baseTranslateUrl level
   * @see baseTranslateUrl
   */
  moduleName?: string;
  /**
   * The base translate URL
   *
   * For example: ./assets/i18n
   * @description the final url will then be: ./assets/i18n/shared if the moduleName is shared
   * @see moduleName
   */
  baseTranslateUrl: string;
  /**
   * The file type of the translation file (JSON only currently)
   */
  fileType: FileType;
  /**
   * By default, it uses the moduleName as nameSpace
   * @see moduleName
   *
   * Use this property if you want to override the default nameSpace
   */
  nameSpace?: string;
  /**
   * Custom translation map function after retrieving a translation file
   * @param translation the resolved translation file
   */
  translateMap?: (translation: Translation) => Translation;
}

Examples

Custom templates for fetching translations

By default, module translations gets fetched by using the following template:

'{baseTranslateUrl}/{moduleName}/{language}{fileType}' e.g.: ./assets/feature1/en.json

You can override this option if you wish to do so:

    const options: IModuleTranslationOptions = {
      ...
      // translates to: ./assets/en/feature1.json
      modulePathTemplate: '{baseTranslateUrl}/{language}/{moduleName}{fileType}'
    };