Using Drupal Actions, Triggers, and Tokens to Send Notifications About Comments

Many blogging tools and CMSes can automatically send out a notification message when new comments are added to a post. Drupal does not have a setting or checkbox to do this automatically. Instead, in typical Drupal fashion, it gives us the tools to set it up ourselves and customize it as desired using "actions" and "triggers".

For this recipe, we will be using the trigger module (core), as well as the token module (contrib). Token module is not strictly required for this task, but it makes it possible to send a much more informative notification.

The first step is to download and install the token module as you would any new module (download and unpack in sites/all/modules/contrib/). Many modules depend on token module, so there is a good chance you actually already have it installed.

Next, go to your Admin -> Site building -> Modules page (admin/build/modules) and enable the new modules:

• Token
• Token actions

While you are on the Modules page, you'll also want to enable the core Trigger module:

Now it is time to make our first "action". In Drupal, actions are individual tasks that the system can perform, such as unpublishing a piece of content or sending an email. Once we've defined our action, we will be using a "trigger" to activate it. So navigate over to Admin -> Site configuration -> Actions (admin/settings/actions). You'll see a list of available actions, and at the bottom of it a dropdown with a list of "advanced actions" we can customize and make available. Select "Send tokenized e-mail..." from the list, and click on "create".

On the form that comes up, we'll first need to describe our new action. Fill in a short, but descriptive title such as "Send tokenized comment notification e-mail" and note the title you gave it since we'll use it later to connect this action to a trigger. The next field to fill in is recipient. Put in "[author-mail]". This is a token (provided by the "Token actions" module for use in actions). We'll look more at tokens in a bit, but for now just know that it will be replaced with the e-mail address of the node's author when the time comes. Next fill in a subject for your email. Something like "[[site-name]] New Comment". The [site-name] token will also be replaced, so the email notification subject will be something like "[Your Sitename] New Comment".

Finally we come to the message field. This is where we can really utilize some of the many tokens made available by the "Token actions" module and use them to format an informative and customized message. Below the message field is a collapsed fieldset labeled "Placeholder tokens". Click on it, and it will open to display dozens of tokens available for use in your message. Scroll through this list to get an idea of just what options are available. When you are ready, fill in a message using the tokens. I usually use something like this:

When you are satisfied with your message, click on "save". This will return you to the actions list, and your new action should be listed.

Now its time to move on to define a trigger that will fire off our new action! Navigate to Admin -> Site building -> Triggers -> Comments (admin/build/trigger/comment). This page lists comment related triggers that can be assigned actions. The very first trigger is "Trigger: After saving a new comment". In the dropdown box for this trigger, select "System - Send tokenized comment notification e-mail" (or whatever title you gave to your action), and click on the "assign" button.

That is it, you have created a custom action, and assigned it to a trigger! Now, to try it out, navigate to a piece of content that you created, and leave a comment. You should receive an e-mail notification about your comment!