Is it possible to use nested merge tags in Mandrill?

Question

Is it possible to use nested merge tags?

What we need is to be able to define the UNSUB tag depending on the values from other merge tags, like on this example:

<a 
href="*|UNSUB:*|COMMUNITYURL|*/site/unsuscribe/user_id/*|USERID|*/hash/*|HASH|*/type/all|*">
Unsubscribe
</a>

Is this correct? Should be done in a different way?

Answer 1

It's not currently possible to nest merge tags. In this case, your best bet would be to add your own List-Unsubscribe headers (using the headers parameter in the API) and pass either your own URL, or a URL constructed with your merge tags but not the UNSUB merge tag.

Answer 2

From the API:

What happens when the [unsubscribe] link is clicked?

If a recipient clicks the generated link, the message status is changed to Unsubscribed and > the recipient's address is added to the Rejection Blacklist in your Mandrill account. The redirect URL will be appended to include two querystring parameters that can be used for processing the unsubscribe in your own system or database:
md_id - the _id, as provided in the API call and webhooks of the specific message where the unsubscribe link was clicked
md_email - a URL-encoded version of the recipient's email address

So you don't have to worry about generating an unsubscribe url for every user. Just put a generic url and mandrill automatically will append to you the email of that user in the md_email variable.

The documentation suggest that you do this then:

<a href="*|UNSUB:http://mywebsite.com/unsub|*">Click here to unsubscribe.</a>

And mandrill will append the correct user email and id:

 http://mywebsite.com/[email protected]&m_id=23321