Update docs

README.md

@@ -23,25 +23,26 @@ Get the changelog by [releases](https://github.com/robisim74/angular-l10n/releas
     - Fallback
     - Custom
 - Caching of the http requests
+- Rollback on error
 - Composed languages: `language[-script][-country]`
 - Language, Default locale & Currency through _ISO codes_
 - Timezone through _IANA_ time zone
 - Cookies, Session & Local Storage, or custom storage (e.g. for using with _Ionic Storage_) available for storing the _ISO codes_
 - _Intl API_ to localize dates & numbers
+- Localized routing for SEO
 - Pure pipes to get the translation
 - Directives to get the translation:
     - can dynamically change parameters and expressions values as the pipes
     - can translate also attributes
     - work also with complex UI components, like _Material_ or _Ionic_
-- Methods to get the translation in component class
-- Html tags in translations
 - Parameters in translations
 - Composed keys in translations (nested objects)
+- Html tags in translations
+- Methods to get the translation in component class
 - AoT compliant
 - Lazy loading compliant
 - Server Side Rendering compliant
 - `strict` TypeScript compiler option compliant
-- Localized routing for SEO
 
 ## Angular i18n solutions
 | _Feature_ | [Angular](https://angular.io/guide/i18n) _Official_ | [ngx-translate](http://www.ngx-translate.com) _External library_ | [angular-l10n](https://robisim74.github.io/angular-l10n) _External library_ |

docs/index.md

@@ -10,7 +10,7 @@ It allows, in addition to translation, to localize numbers and dates of your app
 
 ---
 
-Library version: 6.5.0 - [Changelog](https://github.com/robisim74/angular-l10n/releases) 
+Library version: 6.6.1 - [Changelog](https://github.com/robisim74/angular-l10n/releases) 
 
 ---
 

docs/spec/api.md

@@ -26,7 +26,7 @@ Method | Function
 ## L10nLoader
 Method | Function
 ------ | --------
-`load(): Promise<void>` | Loads l10n services
+`load(): Promise<any>` | Loads l10n services
 
 ---
 
@@ -60,23 +60,22 @@ Method | Function
 `getCurrentTimezone(): string` |
 `setCurrentLanguage(languageCode: string): void` |
 `setDefaultLocale(languageCode: string, countryCode?: string, scriptCode?: string, numberingSystem?: string, calendar?: string): void` |
-`setCurrentNumberingSystem(numberingSystem: string): void` |
-`setCurrentCalendar(calendar: string): void` |
 `setCurrentCurrency(currencyCode: string): void` |
 `setCurrentTimezone(zoneName: string): void` |
 `composeLocale(codes: ISOCode[]): string` |
+`rollback(): void` |
 
 ---
 
 ## ITranslationService
 Property | Value
 -------- | -----
-`translationError: Subject<any>` |
+`translationError: Subject<any>` | Fired when the translation data could not been loaded. Returns the error
 
 Method | Function
 ------ | --------
 `getConfiguration(): TranslationConfig` |
-`init(): Promise<void>` | 
+`init(): Promise<any>` | 
 `translationChanged(): Observable<string>` | Fired when the translation data has been loaded. Returns the translation language
 `translate(keys: string | string[], args?: any, lang?: string): string | any` | Translates a key or an array of keys
 `translateAsync(keys: string | string[], args?: any, lang?: string): Observable<string | any>` |

docs/spec/configuration.md

@@ -131,11 +131,12 @@ Property | Value
 -------- | -----
 `translationData?: Array<{ languageCode: string; data: any; }>` | Direct loading: adds translation data
 `providers?: any[]` |  Asynchronous loading: adds translation providers
-`caching?: Boolean` |  Asynchronous loading: disables/enables the cache for translation providers
-`version?: string` |  Asynchronous loading: adds the query parameter 'ver' to the http requests
-`timeout?: number` |  Asynchronous loading: sets a timeout in milliseconds for the http requests
+`caching?: Boolean` |  Asynchronous loading: disables/enables the cache for translation providers. Provide it only at the root level
+`version?: string` |  Asynchronous loading: adds the query parameter `ver` to the http requests. Provide it only at the root level
+`timeout?: number` |  Asynchronous loading: sets a timeout in milliseconds for the http requests. Provide it only at the root level
+`rollbackOnError?: boolean` |  Asynchronous loading: rollbacks to previous default locale, currency and timezone on error
 `composedLanguage?: ISOCode[]` |  Sets a composed language for translations
-`missingValue?: string | ((path: string) => string)` | Sets the value or the function to use for missing keys
+`missingValue?: string | ((path: string) => string)` | Sets the value or the function to use for missing keys. Provide it only at the root level
 `missingKey?: string` | Sets the key to use for missing keys
 `composedKeySeparator?: string` | Sets composed key separator
 `i18nPlural?: boolean` | Disables/enables the translation of numbers that are contained at the beginning of the keys
@@ -273,7 +274,7 @@ const l10nConfig: L10nConfig = {
 };
 ```
 
-> You can't use Direct and Asynchronous loading at the same time.
+> You can use Direct and Asynchronous loading at the same time. Translation data of Direct loading will be merged before the data of Asynchronous loading.
 
 ### Asynchronous loading through a Web API
 You can also load the data through a Web API:
@@ -289,14 +290,16 @@ const l10nConfig: L10nConfig = {
 ...
 export class AppModule {
     constructor(private translation: TranslationService) {
-        this.translation.translationError.subscribe((error: any) => console.log(error));
+        this.translation.translationError.subscribe((error) => {
+            if (error) {
+                console.log(error);
+            }
+        });
     }
 }
 ```
 `[path]{languageCode}` will be the URL used by the Http GET requests. So the example URI will be something like: `http://localhost:54703/api/values/en`.
 
-The example above also showed as you can perform a custom action if you get a bad response.
-
 ### Using fallback providers
 if you need a cascade fallback when the key is not found, you can use fallback providers:
 ```TypeScript
@@ -352,6 +355,68 @@ See also [TranslationProvider](https://github.com/robisim74/angular-l10n/blob/ma
 
 ---
 
+## Caching
+You can enable the cache during configuration:
+```TypeScript
+const l10nConfig: L10nConfig = {
+    ...
+    translation: {
+        providers: [
+            { type: ProviderType.Static, prefix: './assets/global-' },
+            { type: ProviderType.Static, prefix: './assets/locale-' }
+        ],
+        caching: true
+    }
+};
+```
+The next time a translation file will be required, will be taken from the cache without making a new _http request_, with a significant performance improvement:
+
+* if the user returns to a language already selected;
+* if you use a global file shared across _lazy loaded modules_.
+
+---
+
+## Error handling of data loading
+To find out if an error occurred during asynchronous loading of translation data, you have the `translationError` event:
+```TypeScript
+...
+export class AppComponent {
+    constructor(private translation: TranslationService) {
+        this.translation.translationError.subscribe((error) => {
+            if (error) {
+                console.log(error);
+            }
+        });
+    }
+}
+```
+If the error occurs on the first loading of the application or a lazy loaded module, you can catch it with the `load` method: 
+```TypeScript
+export class AppModule {
+    constructor(public l10nLoader: L10nLoader) {
+        this.l10nLoader.load()
+            .catch(err => console.error(err));
+    }
+}
+```
+
+> If you use _advanced initialization_, you can catch it with the `bootstrapModule` method in `main.ts`.
+
+### Rollback on errror
+If the error occurs when the user changes language, you can enable `rollbackOnError` option during the configuration:
+```TypeScript
+const l10nConfig: L10nConfig = {
+    ...
+    translation: {
+        ...
+        rollbackOnError: true
+    }
+};
+```
+In this way, the application will keep the previous locatization without changing settings.
+
+---
+
 ## Using a composed language
 By default, the `languageCode` is added as extension to the translation files. If you set `composedLanguage` during the configuration, the combination of supplied codes will be used as language:
 ```TypeScript
@@ -461,27 +526,6 @@ That's because not all browsers return `languageCode-countryCode`.
 
 ---
 
-## Caching
-You can enable the cache during configuration:
-```TypeScript
-const l10nConfig: L10nConfig = {
-    ...
-    translation: {
-        providers: [
-            { type: ProviderType.Static, prefix: './assets/global-' },
-            { type: ProviderType.Static, prefix: './assets/locale-' }
-        ],
-        caching: true
-    }
-};
-```
-The next time a translation file will be required, will be taken from the cache without making a new _http request_, with a significant performance improvement:
-
-* if the user returns to a language already selected;
-* if you use a global file shared across _lazy loaded modules_.
-
----
-
 ## Intl API
 To localize _dates and numbers_, this library uses the [Intl API](https://developer.mozilla.org/it/docs/Web/JavaScript/Reference/Global_Objects/Intl).
 
@@ -591,7 +635,7 @@ const l10nConfig: L10nConfig = {
 };
 ```
 
-### Setting the locale in _Accept-Language_ header on outgoing requests
+## Setting the locale in _Accept-Language_ header on outgoing requests
 To set the locale in _Accept-Language_ header on all outgoing requests, provide the _localeInterceptor_ option during the configuration:
 ```TypeScript
 const l10nConfig: L10nConfig = {

docs/spec/getting-the-translation.md

@@ -315,6 +315,28 @@ Using _directives_:
 
 ---
 
+## Pluralization
+The library implements pluralization through the official [i18nPluralPipe](https://angular.io/api/common/I18nPluralPipe). Just add to it the translate pipe:
+```Html
+<p>{{ messages.length | i18nPlural:messageMapping | translate:lang }}</p>
+```
+or the directive:
+```Html
+<p l10nTranslate>{{ messages.length | i18nPlural:messageMapping }}</p>
+```
+and enable `i18nPlural` option during the configuration:
+```TypeScript
+const l10nConfig: L10nConfig = {
+    ...
+    translation: {
+        ...
+        i18nPlural: true
+    }
+};
+```
+
+---
+
 ## Getting the translation in component class
 ### Messages
 To get the translation in component class, `TranslationService` has the following methods:

package.json

@@ -1,7 +1,7 @@
 {
     "name": "angular-l10n",
     "private": true,
-    "version": "6.5.0",
+    "version": "6.6.1",
     "description": "An Angular library to translate messages, dates and numbers",
     "main": "./bundles/angular-l10n.umd.js",
     "module": "./fesm5/angular-l10n.js",