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Sending ticket notifications
Before you go about configuring your application to send emails into the real
world, you’ll add two more features to Ticketee. The first feature automatically subscribes
a user to a watchers list whenever that user creates a ticket. Every time this
ticket is updated by another user, the creator of the ticket should receive an email.
This is helpful, because it allows users to keep up-to-date with the tickets that they
have created. The second feature will allow users to add themselves to or remove
themselves from the watching list for a given ticket.
With these features in place, all users who are watching a ticket will be notified via
email that a comment has been posted to the ticket, what that comment was, and any
state change that took place. This email message will additionally contain a link to the
ticket and a link to unsubscribe from further notifications regarding the ticket. If a
user posts a comment to a ticket and they’re not watching it, then they will automatically
begin to watch it. They can unsubscribe later if they wish by following the unsubscribe
link in the email. Email is a tried-and-true solution to receiving notifications of
events such as this.
Once that’s all said and done, you’ll work on sending emails through an actual
server—Gmail—which will test that your application is able to send out emails into the
real world and that you’re doing everything you can to let your users receive them.
Gmail is great for low-volume sending, 2 but if you needed something with a larger
capacity, other services such as SendGrid 3 and MailChimp 4 are acceptable alternatives.
Although we don’t look at how to use large-volume services in this chapter, it’s always
great to be aware of alternatives, should you ever need to scale up. To check for the
emails on a Gmail account, you’ll be using the (unofficial) 5 gmail gem.
After spending most of the chapter looking at how to send emails, you’ll take a look
at how to receive them using the gmail gem and Action Mailer. When a user receives an
email notifying them that a comment has been posted to a ticket, they will be able to
send a reply that you can read using both the gmail gem and Action Mailer. You’ll also
be able to create a new comment from their reply’s text. Nifty stuff.
The first thing you’re going to do is set up a way for users to receive notifications
when a comment is posted to a ticket they’ve created. Let’s dive into creating the feature
and code for this functionality now.
12.1 Sending ticket notifications
The next feature of your application will provide users with the ability to watch a
ticket. You’ll build off this functionality to notify users by email that a ticket has been
updated any time somebody posts a comment to it. This email will contain the name
of the user who updated the ticket, the comment text, a URL to the ticket, and finally
a link to unsubscribe from all future ticket updates.
2 Gmail has a daily send limit of 200 emails.
3 http://sendgrid.com.
4 http://mailchimp.com.
5 As in, not sponsored by Google.
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