Add Mailer events

[tacruc]

I'm working on an APP implementing the ability to send encrypted emails to registered users #7310.
Therefor a two small modifications are needed.

• An Hook in scope \OC\Mail preSendMessage(IMessage $message)
• And the function OC\Mail\Massage::setSwiftMessage, to replace unencrypted swiftmessage with the encrypted one.

The rest is fixing a bug if swiftMessage->getX() is returning NULL

[tacruc]

I think the last failures are independent of the commits.
One is a timeout on Publish-S3

The second is not failing in the last build
TESTS-ACCEPTANCE=users

 Scenario: create a new user # /drone/src/github.com/nextcloud/server/tests/acceptance/features/users.feature:4
Given I act as Jane # ActorContext::iActAs()
And I am logged in as the admin # LoginPageContext::iAmLoggedInAsTheAdmin()
And I open the User settings # SettingsMenuContext::iOpenTheUserSettings()
And I click the New user button # UsersSettingsContext::iClickTheNewUserButton()
New user button in Users Settings could not be found (NoSuchElementException)
And I see that the new user form is shown # UsersSettingsContext::iSeeThatTheNewUserFormIsShown()
When I create user unknownUser with password 123456acb # UsersSettingsContext::iCreateUserWithPassword()
Then I see that the list of users contains the user unknownUser # UsersSettingsContext::iSeeThatTheListOfUsersContainsTheUser()

[kesselb]

@rullzer there are no hooks in \OC\Mail. Could we use Events instead of Hooks here?

[tacruc]

@kesselb cloud you add the to review flag?

[tacruc]

@kesselb can you help me, where I can find more information about events. It is important that the email is not send until the call to the app is finished, otherwise an unencrypted email is send.

[tacruc]

I have changed it, to not create a hook, but use the dispatcher to dispatch a event \OC\Mail::preSendMessage

[kesselb]

Hmm. Not sure about this one but i would pass $message as $subject to GenericEvent instead of null.

[tacruc]

Where would be the place to document the event? Or is there a list of all available events?

[tacruc]

@nextcloud/documentation Is there a place where all the available events are documented? For the available Hooks there is but I cloudn't find something for events.

[tacruc]

rebased to master

[ChristophWurst]

As just discussed we should

• Create a typed \OCP\Mail\Events\BeforeMessageSent in lib/public/Mail/Events
• Add setSwiftMessage in the internal Message class
• Use the internal class in https://github.com/tacruc/gpgmailer/blob/4f7fdee2eefcf4d56bfa393c369b7e88ca3a243f/lib/Hooks/MailHooks.php

(exposing an abstraction of Swift is a lot of work and not worth the effort here)

Example event: https://github.com/nextcloud/server/blob/master/lib/public/User/Events/BeforeUserDeletedEvent.php
Example hook to events migration: d808f9c#diff-b9e7943dc8f2ede028acf951e8853ff1
The event dispatcher: https://github.com/nextcloud/server/blob/master/lib/public/EventDispatcher/IEventDispatcher.php

[ChristophWurst]

Indentation is off in a few places. Could you check those as well?

[tacruc]

Indentation

Found three errors in 2 files, did I miss some place?

[ChristophWurst]

Update @since tags. Otherwise fine by me 👍

[ChristophWurst]

Suggested change

	* @since 18.0.0
	* @since 19.0.0

[MorrisJobke]

ref #14552