This follows this conversation:#36629 (comment) - it automatically adds SQL to Doctrine's migration/diff system when features are added the require a database table:

The new feature works for:

A) Messenger Doctrine transport

FULL support
Works perfectly: configure a doctrine transport and runmake:migration

Note: There is no current way to disable this. So if you haveauto_setup ON and you
runmake:migration before trying Messenger, it will generate the table SQL. Adding a
flag to disable it might be very complicated, because we need to know (in DoctrineBundle, at compile time) whether or not this feature is enabled/disabled so that we can decidenot to addmessenger_messages to theschema_filter.

B)PdoAdapter from Cache

FULL support
Works perfectly: configure a doctrine transport and runmake:migration

C)PdoStore from Lock

PARTIAL support
I addedPdoStore::configureSchema() but did NOT add a listener. WhilePdoStoredoes accept a DBALConnection, I don't think it's possible via theframework.lock config to create aPdoStore that is passed aConnection. In other words: if we added a listener that calledPdoStore::configureSchema if the user configured apdo lock, that service willnever have aConnection object... so it's kind of worthless.

NEED: A proper way to inject a DBALConnection intoPdoStore viaframework.lock config.

D)PdoSessionHandler

NO support

This class doesn't accept a DBALConnection object. And so, we can't reliably create a listener to add the schema because (if there are multiple connections) we wouldn't know which Connection to use.

We could compare (===) thePDO instance insidePdoSessionHandler to the wrappedPDO connection in Doctrine. That would only work if the user has configured theirPdoSessionHandler to re-use the Doctrine PDO connection.

ThePdoSessionHandleralready has acreateTable() method on it to help with manual migration. But... it's not easy to call from a migration because you would need to fetch thePdoSessionHandler service from the container. Adding something

NEED: Either:

A) A way forPdoSessionHandler to use a DBAL Connection
or
B) We try to hack this feature by comparing thePDO instances in the event subscriber
or
C) We add an easier way to access thecreateTable() method from inside a migration.

TODOs

• Determine service injection XML needed for getting all PdoAdapter pools
• Finish DoctrineBundle PR:Add support for new MessengerTransportDoctrineSchemaSubscriber doctrine/DoctrineBundle#1163