How to attach messages from a mailbox?

Question

PHP

I am developing a service, I need to solve the following problem, there will be a list of users of several tens of thousands, each user will have a unique address, when sent to which an entry will be created in the interface of this user.

Answer 1

You complicate your life, dovecot is not needed here if you are not creating a full-fledged mail server (this is by the way that the dovecot tag is clearly superfluous here).
To add received messages to the database, it is enough to connect the transport to postfix in the form of a backend on any php, which will parse incoming messages and add them to the database in the desired format.
Google for "postfix transport pipe".

Answer 2

Why copy a hundred times back and forth, dovecot can use the database as storage, bind to the user's account and that's it.