Asymmetrik/mean2-starter

'use strict';

const _ = require('lodash'),
    fs = require('fs'),
    https = require('https'),
    path = require('path'),

    deps = require(path.resolve('./src/server/dependencies.js')),
    logger = deps.logger;

let config = {};

const generateOptions = () => {
    const options = {
        hostname: config.hostname,
        port: config.port,
        ca: config.ca,
        cert: config.cert,
        key: config.key,
        passphrase: config.passphrase,
        headers: {
            Accept: 'application/json'
        }
    };

    options.agent = new https.Agent(options);

    return options;
};

/**
 * Converts the input mail options to a format expected by the HTTPS service
 * @param {object} mailOptions <p>Configuration for mail options with input values as:
 * <pre>{
 *   'to': '',
 *   'cc': '',
 *   'bcc': '',
 *   'from': '',
 *   'subject': '',
 *   'text': '',
 *   'html': ''
 * }</pre>
 * One of 'text' or 'html' is expected</p>
 */
const transformMailOptions = (mailOptions) => {
    // Any transformations required for the mail options would go here
    return mailOptions;
};

/**
 * Sends an email with the input mail options by posting to a configured HTTPS endpoint
 * @param {object} mailOptions <p>Configuration for mail options with input values as:
 * <pre>{
 *   'to': '',
 *   'cc': '',
 *   'bcc': '',
 *   'from': '',
 *   'subject': '',
 *   'text': '',
 *   'html': ''
 * }</pre>
 * One of 'text' or 'html' is expected</p>
 */
const sendMail = (mailOptions) => {

    return new Promise((resolve, reject) => {
        const postData = JSON.stringify(transformMailOptions(mailOptions));
        const options = generateOptions();
        options.path = config.paths.within;
        options.method = 'POST';
        options.headers = options.headers || {};
        options.headers['Content-Type'] = 'application/json';
        options.headers['Content-Length'] = Buffer.byteLength(postData); // Buffer is globally defined by node.js

        let data = '';
        const req = https.request(options, (res) => {
            res.on('data', (chunk) => {
                data += chunk;
            });
            res.on('end', () => {
                if(res.statusCode === 404) {
                    reject('Email service not found');
                }
                else if(res.statusCode !== 200) {
                    reject(data); // send back the error
                }
                else {
                    // 200 response
                    const result = JSON.parse(data);
                    resolve(result);
                }
            });
        });

        req.on('error', (err) => {
            reject(err);
        });

        req.write(postData);
        req.end();
    });

};

// https-email provider requires configuration to be passed in
module.exports = function(inputConfig) {

    config = inputConfig;

    logger.debug('Using HTTPS-based Email service');

    if(_.isString(config.ca)) { config.ca = fs.readFileSync(config.ca); }
    if(_.isString(config.cert)) { config.cert = fs.readFileSync(config.cert); }
    if(_.isString(config.key)) { config.key = fs.readFileSync(config.key); }

    return {
        sendMail
    };
};