How can I send an email using the Rules module to a user specified via Entity Reference in a Content Type? This question is similar to others posed, but all the answers I can find appear to refer to Drupal 6, with CCK fields.

I am using Drupal 7 with the Rules module enabled.

I have created a custom Content Type and one of the fields is an Entity Reference, which allows a registered user to be selected as the Content Type is added. Essentially an administrator can associate a registered website user with the content item being added.

I need to email the referenced user when another field value within the Content Type is changed. I'm sure this is possible via the Rules module, but I cannot get the mail to send.

It must be a fairly common situation, emailing a referenced user when a field value is updated, but I have looked at the online notes for the Rules module and cannot find an example of this particular use case.

Has anybody managed to achieve the same outcome as I am seeking?

Thank you.
After some trial and error, I found how to reference the field.

Within the Conditions section of the rule, I needed to:


Add "entity has field"
Enter "node" within the Data Selector box
Select the entity reference field within the Value dropdown


I was then able to refer to the field required, with the mail parameter appended, directly from a standard Send Mail action (i.e. [node:MY-REFERENCED-FIELD:mail]).