Implement Email DAO for sending verification mails

src/dao/email.js

@@ -17,6 +17,9 @@
 
 'use strict';
 
+const log = require('npmlog');
+const util = require('../service/util');
+
 /**
  * A simple wrapper around Nodemailer to send verification emails
  */
@@ -30,21 +33,131 @@ class Email {
     this._mailer = mailer;
   }
 
+  /**
+   * Create an instance of the reusable nodemailer SMTP transport.
+   * @param {string} host          The SMTP server's hostname e.g. 'smtp.gmail.com'
+   * @param {Object} auth          Auth credential e.g. { user:'user@gmail.com', pass:'pass' }
+   * @param {Object} sender        The message 'FROM' field e.g. { name:'Your Support', email:'noreply@exmple.com' }
+   * @param {string} port          (optional) The SMTP server's SMTP port. Defaults to 465.
+   * @param {boolean} secure       (optional) If TSL should be used. Defaults to true.
+   * @param {boolean} requireTLS   (optional) If TSL is mandatory. Defaults to true.
+   */
+  init(options) {
+    this._transport = this._mailer.createTransport({
+      host: options.host,
+      port: options.port || 465,
+      auth: options.auth,
+      secure: options.secure || true,
+      requireTLS: options.requireTLS || true
+    });
+    this._sender = options.sender;
+  }
+
+  /**
+   * A generic method to send an email message via nodemail.
+   * @param {Object} from      The sender user id object e.g. { name:'Jon Smith', email:'j@smith.com' }
+   * @param {Object} to        The recipient user id object e.g. { name:'Jon Smith', email:'j@smith.com' }
+   * @param {string} subject   The message subject
+   * @param {string} text      The message plaintext body
+   * @param {string} html      The message html body
+   * @yield {Object}           The reponse object containing SMTP info
+   */
+  *send(options) {
+    let mailOptions = {
+      from: {
+        name: options.from.name,
+        address: options.from.email
+      },
+      to: {
+        name: options.to.name,
+        address: options.to.email
+      },
+      subject: options.subject,
+      text: options.text,
+      html: options.html
+    };
+
+    try {
+      let info = yield this._transport.sendMail(mailOptions);
+      log.silly('email', 'Email sent.', info);
+      return info;
+    } catch(error) {
+      log.error('email', 'Sending email failed.', error, options);
+      throw error;
+    }
+  }
+
   /**
    * Send the verification email to the user to verify email address
    * ownership. If the primary email address is provided, only one email
    * will be sent out. Otherwise all of the PGP key's user IDs will be
    * verified, resulting in an email sent per user ID.
-   * @param {Array} options.userIds        The user id documents containing the nonces
-   * @param {Array} options.primaryEmail   (optional) The user's primary email address
+   * @param {Array}  userIds        The user id documents containing the nonces
+   * @param {Array}  primaryEmail   (optional) The user's primary email address
+   * @param {Object} origin         Required for links to the keyserver e.g. { protocol:'https', host:'openpgpkeys@example.com' }
    * @yield {undefined}
    */
-  sendVerification() {
-    return Promise.resolve();
+  *sendVerification(options) {
+    let primaryEmail = options.primaryEmail, userIds = options.userIds, origin = options.origin;
+    let primaryUserId = userIds.find(uid => uid.email === primaryEmail);
+    if (primaryUserId) { // send only one email to the primary user id
+      return yield this._sendVerificationHelper(primaryUserId, origin);
+    }
+    for (let uid of userIds) {
+      yield this._sendVerificationHelper(uid, origin);
+    }
   }
 
-  send() {
+  /**
+   * Help method to send a verification message
+   * @param {Object} userId   The user id document
+   * @param {Object} origin   The origin of the server
+   * @yield {Object}          The send response from the SMTP server
+   */
+  *_sendVerificationHelper(userId, origin) {
+    let message = this._createVerifyMessage(userId, origin);
+    try {
+      let info = yield this.send(message);
+      if (!this._checkResponse(info)) {
+        log.warn('email', 'Verification mail may not have been received.', info);
+      }
+      return info;
+    } catch(e) {
+      util.throw(500, 'Sending verification email failed');
+    }
+  }
 
+  /**
+   * Helper function to create a verification message object.
+   * @param  {Object} userId   The user id document
+   * @param  {Object} origin   The origin of the server
+   * @return {Object}          The message object
+   */
+  _createVerifyMessage(userId, origin) {
+    let verifyLink = origin.protocol + '://' + origin.host +
+      '/api/v1/verify/?keyid=' + encodeURIComponent(userId.keyid) +
+      '&nonce=' + encodeURIComponent(userId.nonce);
+    let text = `Hey${userId.name ? ' ' + userId.name : ''},
+
+please click here to verify your key: ${verifyLink}
+`;
+
+    return {
+      from: this._sender,
+      to: userId,
+      subject: 'Verify Your Key',
+      text: text
+    };
+  }
+
+  /**
+   * Check if the message was sent successfully according to SMTP
+   * reply codes: http://www.supermailer.de/smtp_reply_codes.htm
+   * @param  {Object} info   The info object return from nodemailer
+   * @return {boolean}       If the message was received by the user
+   */
+  _checkResponse(info) {
+    return /^2/.test(info.response);
   }
 
 }