jalik-mailer

Mailer is a Meteor package that provides a simple way to send emails using a prioritized queue system.
It was built to never miss an email sending even if the server is restarted.

Installation

To install the package, execute this command in the root of your project :

meteor add jalik:mailer

If later you want to remove the package :

meteor remove jalik:mailer

Configuration

All settings are accessible from the Mailer.config object which is an instance of MailerConfig with default settings.

import {Mailer} from 'meteor/jalik:mailer';
// default from address to use
Mailer.config.from = 'me@mail.com';
// send emails asynchronously
Mailer.config.async = true;
// send emails every 60 seconds
Mailer.config.interval = 1000 * 60;
// send max 5 emails per task (in this example a task is run every 60 seconds) /  (0 to disable)
Mailer.config.maxEmailsPerTask = 5;
// max time before considering that a sending email has failed
Mailer.config.maxSendingTime = 1000 * 30;
// default priority (ex= 1 is more important than 5)
Mailer.config.priority = 2;
// Send email when service starts
Mailer.config.processOnStart = true;
// number of time to retry when email sending failed (0 to disable)
Mailer.config.retry = 1;
// web hook path used to mark emails as read
Mailer.config.webHook = 'mailer';

Starting the service

To start the mail service, use Mailer.start().

import {Mailer} from 'meteor/jalik:mailer';
import {Meteor} from 'meteor/meteor';
if (Meteor.isServer) {
    Meteor.startup(function () {
        Mailer.start();
    });
}

Stopping the service

To stop the mail service, use Mailer.stop().

import {Mailer} from 'meteor/jalik:mailer';
import {Meteor} from 'meteor/meteor';
if (Meteor.isServer) {
    Meteor.startup(function () {
        Mailer.start();
        //...
        Mailer.stop();
    });
}

Restarting the service

To restart the mail service, use Mailer.restart().

import {Mailer} from 'meteor/jalik:mailer';
import {Meteor} from 'meteor/meteor';
if (Meteor.isServer) {
    Meteor.startup(function () {
        Mailer.start();
        //...
        Mailer.restart();
    });
}

Sending emails

To send an email, use Mailer.send(email), the content of the email can be raw text if you pass the text option and/or HTML if you pass html.
The email object is the same as in the Meteor documentation : https://docs.meteor.com/api/email.html since Mailer is a smart version of the Email package.
Sending an email will put it in the queue and send it just after.

import {Mailer} from 'meteor/jalik:mailer';
Mailer.send({
    from: 'test@mailer.com',
    bcc: ['bcc@example.com'],
    cc: ['cc1@example.com','cc2@example.com'],
    to: 'you@example.com',
    subject: 'Test email',
    text: "Mailer Test",
    html: "<h1>Mailer Test</h1>",
    // Optional: tells the mailer when to send the email
    sendAt: new Date(Date.now() + 1000*60*60)
});

Adding emails to queue

To send an email that is not urgent, use Mailer.queue(email).
You can manage the order of the queue by setting the priority (ex: 0 will be sent before 99).

import {Mailer} from 'meteor/jalik:mailer';
Mailer.queue({
    from: 'test@mailer.com',
    to: 'you@example.com',
    subject: 'Test email',
    text: "Mailer Test",
    // Optional: this tells the mailer to send this email before emails with priority more than 2
    priority: 2
});

Handling errors

Sometimes errors can happen, in that case the Mailer will simply change the status of the email to failed and will retry to send it on the next execution.
But if you want to do more things you can overwrite the Mailer.onError callback.

import {Mailer} from 'meteor/jalik:mailer';
Mailer.onError = function(err, emailId) {
    console.error(err);
};

Handling events

You can hook to mailer events by using the following methods.

import {Mailer} from 'meteor/jalik:mailer';
Mailer.onEmailDelayed = function(emailId, email) {
    console.log(`The email ${emailId} has been delayed`);
};
Mailer.onEmailFailed = function(emailId, email) {
    console.log(`The email ${emailId} has failed sending`);
};
Mailer.onEmailQueued = function(emailId, email) {
    console.log(`The email ${emailId} has been added to queue`);
};
Mailer.onEmailRead = function(emailId, httpRequest) {
    console.log(`The email ${emailId} has been read`);
};
Mailer.onEmailSent = function(emailId, email) {
    console.log(`The email ${emailId} has been sent`);
};
Mailer.onSend = function(emailId, email) {
    console.log(`Sending email ${emailId}`);
};

Fetching emails

All emails are stored in a Mongo.Collection, accessible in Mailer.emails.

let count = 0;
import {Mailer} from 'meteor/jalik:mailer';
count = Mailer.emails.find({status: Mailer.status.PENDING}).count();
// OR
import {Emails} from 'meteor/jalik:mailer';
count = Emails.find({status: Mailer.status.PENDING}).count();

Email status

Each email have a status attribute that can be one of the following :

• pending : the email has been added to the queue and is waiting to be sent
• canceled : the email has been canceled
• failed : an error occurred while sending the email, it will be sent on the next execution
• delayed : the email will be sent on the next execution because it took too much time to be sent
• sending : the email is currently sending
• sent : the email has been sent
• read : the email has been read (note that it works only with html emails using an embedded img tag)

NOTE: statuses are available through Mailer.status.

Changelog

v0.4.0

WARNING, there are breaking changes in this version, please see below.

• Deprecates method Mailer.getReadLink(), use instead Mailer.getReadUrl()
• Deprecates method Mailer.sendEmail(), use instead Mailer.processEmail()
• Renames class Mailer.Config to MailerConfig

These are the new things :

• Uses ES6 module import and export syntax
• Adds Mailer.status containing all email statuses
• Adds config Mailer.config.processOnStart = true to send emails when service starts
• Adds method Mailer.cancelEmail(emailId)
• Adds method Mailer.checkEmail(email)
• Adds method Mailer.getReadPath(emailId, redirect)
• Adds method Mailer.getReadUrl(emailId, redirect)
• Adds method Mailer.isStarted()
• Adds method Mailer.onStarted(callback)
• Adds method Mailer.onStopped(callback)
• Adds method Mailer.processEmail()
• Adds method Mailer.replaceLinks(content, emailId)
• Adds method Mailer.restart()
• Adds method Mailer.stop()
• Adds unit tests
• Throws more detailed errors

License

This project is released under the MIT License.