View source for Sieve-Example:Move email to a suffix folder

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==Description==
Say you have a single mailbox:
 me@example.com

And you want to give out 'unique' addresses to companies so that you can control who has your address and helps you track and filter your email. You may want to give out addresses such as:
 me-amazon@example.com
 me-ebay@example.com

This is all possible with two things:
*An alias - set on the Control Pages
*(optionally) A sieve filter

==Alias==
On the control pages, in the email setup, under aliases create an alias such as:
[[File:Email alias for suffix.png|thumb|none|500|Alias]]
This sends messages addressed to me-ANYTHING@example.com to the me Mailbox

==Sieve filter==
Optionally, you can magically move these messages in folders...

Once messages are being sent to your Inbox with the alias above, you can create a sieve filter to automatically move messages to their folder, if you've made the folder already. 

<syntaxhighlight>
require ["fileinto","imap4flags","variables","regex","mailbox"];

## Move messages sent to an address with a suffix eg, me-amazon@example.com in to a folder called Filtered/amazon, if it exists.
if exists "X-Delivered-To" {

         if header :regex "X-Delivered-To" "-([A-z0-9]+)@" {
                set "suffix" "${1}";
                fileinto "INBOX.Filtered.${suffix}";
        } 
        stop;}
</syntaxhighlight>

*This filter uses the 'X-Delivered-To' header which is added by the A&A mail servers - even if you are BCC'd then the filtering will work. The X-Delivered-To is the 'envelope-to' header, which is the address the email was actually sent to by the sender (in lowercase).
*You'll need to add this sieve filter - eg by using the (latest) Thunderbird Sieve extension, see [https://support.aa.net.uk/Sieve_Filtering#Sieve_Server_Settings Sieve_Server_Settings] for info in the 'Creating Sieve Filters' section
*This won't be able to be added via Roundcube, as you can't paste in raw sieve code there.

===Variations===
You can create the folders automatically if you wanted add :create,  - but some mail clients won't refresh their folder list until they are restarted.  We also title case the new folder name - eg it will be called Amazon (capital A).
                set :upperfirst "suffix" "${1}";
                fileinto :create "INBOX.Filtered.${suffix}";

== Create the folders ==
The sieve filter puts email in to a folder called Filtered/XXX, and as long as XXX matches the suffix in the email address, the messages will get moved to there.
So in your email program:
#Create a folder called: Filtered
#Create folders within Filtered for the suffix you want filtered there

[[File:Email folders.png|thumb|none|100|Folder layout in your email client]]