# i18nextPlugin

A plugin to faciliate the integration of i18next in a federated application.

# Reference

const plugin = new i18nextPlugin(supportedLanguages: [], fallbackLanguage, queryStringKey, options?: { detection?: {} })

# Parameters

supportedLanguages: An array of languages supported by the application.
fallbackLanguage: The language to default to if none of the detected user's languages match any supported language.
queryStringKey: The querystring parameter lookup when detecting the user's language.
options: An optional object literal of options:
- detection: An optional object literal accepting any LanguageDetector options.

# Usage

# Register the plugin

import { i18nextPlugin } from "@squide/i18next";
import { FireflyRuntime } from "@squide/firefly";

const runtime = new FireflyRuntime({
    plugins: [new i18nextPlugin(["en-US", "fr-CA"], "en-US", "language")]
});

# Retrieve the plugin instance

import { i18nextPlugin } from "@squide/i18next";

const plugin = runtime.getPlugin(i18nextPlugin.name) as i18nextPlugin;

Prefer using getI18nextPlugin when possible

../geti18nextplugin/

# Register a i18next instance

import { i18nextPlugin } from "@squide/i18next";
import i18n from "./i18next";
import resourcesEn from "./locales/en.json";
import resourcesFr from "./locales/fr.json";

const instance = i18n.createInstance({
    resources: {
        "en-US": resourcesEn,
        "fr-CA": resourcesFr
    }
});

const plugin = runtime.getPlugin(i18nextPlugin.name) as i18nextPlugin;

plugin.registerInstance("an-instance-key", instance);

# Retrieve a i18next instance

import { i18nextPlugin } from "@squide/i18next";

const plugin = runtime.getPlugin(i18nextPlugin.name) as i18nextPlugin;

// If no instance match the specified key, an error will be thrown.
const instance = plugin.getInstance("an-instance-key");

# Detect the user language

Whenever a plugin instance is created, the user's language should always be detected immediatly using the detectUserLanguage function.

import { i18nextPlugin } from "@squide/i18next";
import { FireflyRuntime } from "@squide/firefly";

const plugin = new i18nextPlugin(["en-US", "fr-CA"], "en-US", "language");

// If no detected languages match any of the supported languages, the fallback language will be applied.
plugin.detectUserLanguage();

const runtime = new FireflyRuntime({
    plugins: [plugin]
});

# Retrieve the current language

import { i18nextPlugin } from "@squide/i18next";

const plugin = runtime.getPlugin(i18nextPlugin.name) as i18nextPlugin;

// If the language hasn't been changed nor detected before getting the current language, an error will be thrown.
const language = plugin.currentLanguage;

# Change the current language

import { i18nextPlugin } from "@squide/i18next";

const plugin = runtime.getPlugin(i18nextPlugin.name) as i18nextPlugin;

// If the language isn't included in the "supportedLanguages" array, an error will be thrown.
plugin.changeLanguage("fr-CA");

# Change the language detection order

By default, the detection of the user's language is done first from the specified URL querystring parameter (?language in this example), then from the user's navigator language settings. The detection order can be changed by specifying a new value for the order detection option:

const plugin = new i18nextPlugin(["en-US", "fr-CA"], "en-US", "language", {
    detection: {
        // Change the detection order to lookup the user browser default languages before the querystring parameter.
        order: ["navigator", "querystring"]
    }
});

# Add an additional detection source

const plugin = new i18nextPlugin(["en-US", "fr-CA"], "en-US", "language", {
    detection: {
        order: [
            "querystring",
            // Will look for a language in the local storage before detecting the language from the user browser defaults.
            "localStorage",
            "navigator",
        ],
        lookupLocalStorage: "my-local-storage-key"
    }
});