How To Write Reusable and Testable Code with Microsoft Bot Framework

welcome.js

"use strict";
const builder = require("botbuilder");
const library = new builder.Library('welcome'); // welcome is a library name

const LANGUAGES = {'English': 'en', 'Русский': 'ru'};

library.dialog('/pickLocale', [
    (session) => {
        // Prompt the user to select their preferred locale
        builder.Prompts.choice(session, "What language do you prefer?", Object.keys(LANGUAGES).join("|"));
    },
    (session, results) => {
        // Update preferred locale
        let locale = LANGUAGES[results.response.entity];
        session.preferredLocale(locale, (err) => {
            if (err) {
                // Problem loading the selected locale
                session.error(err);
            } else {
                // Locale files loaded
                session.endDialog("locale_set", results.response.entity);
            }
        });
    }
]);

library.dialog('/showWelcomeMessage', [
    (session) => session.endDialog("welcome")
]);

module.exports = library;