Correctly remove usergroup shares on removing group members

[nickvergessen]

Steps

1. As admin create a group and assign userA to the group
2. Share a file to the group
3. As userA edit the file
4. As admin remove userA from the group
5. Check share table (there is still a usergroup share entry for userA before this PR)
6. As admin modify the file
7. As userA check your activity (there is a new entry before this PR)

There seems to be inconsistency for LDAP and other group backends. The listened old hook 'OC_User', 'post_removeFromGroup' is not emitted in the normal user/group backend since 16 at least?

[faily-bot]

🤖 beep boop beep 🤖

Here are the logs for the failed build:

Status of 31122: failure

integration-auth

• build/integration/features/auth.feature:70

Show full log

  Scenario: using OCS anonymously                                                    # /drone/src/build/integration/features/auth.feature:70
[Mon Jul 27 11:18:22 2020] 127.0.0.1:41962 [404]: /ocs/v2.php/cloud/users/user0
[Mon Jul 27 11:18:22 2020] 127.0.0.1:41986 [200]: /ocs/v1.php/cloud/users
[Mon Jul 27 11:18:23 2020] 127.0.0.1:42014 [200]: /ocs/v1.php/cloud/users/user0
[Mon Jul 27 11:18:23 2020] 127.0.0.1:42032 [200]: /ocs/v2.php/cloud/users/user0
[Mon Jul 27 11:18:23 2020] 127.0.0.1:42044 [200]: /login
[Mon Jul 27 11:18:23 2020] 127.0.0.1:42046 [303]: /login
[Mon Jul 27 11:18:23 2020] 127.0.0.1:42056 [200]: /index.php/apps/files/
[Mon Jul 27 11:18:23 2020] 127.0.0.1:42060 [200]: /index.php/settings/personal/authtokens
[Mon Jul 27 11:18:23 2020] 127.0.0.1:42064 [200]: /index.php/settings/personal/authtokens/56
[Mon Jul 27 11:18:23 2020] 127.0.0.1:42066 [303]: /login
[Mon Jul 27 11:18:23 2020] 127.0.0.1:42068 [200]: /index.php/apps/files/
[Mon Jul 27 11:18:29 2020] 127.0.0.1:42072 [303]: /login
[Mon Jul 27 11:18:29 2020] 127.0.0.1:42164 [200]: /index.php/apps/files/
[Mon Jul 27 11:18:29 2020] 127.0.0.1:42170 [200]: /index.php/settings/personal/authtokens
[Mon Jul 27 11:18:29 2020] TypeError: Argument 11 passed to OCA\Files_Sharing\External\Manager::__construct() must be of the type string, null given, called in /drone/src/apps/files_sharing/lib/AppInfo/Application.php on line 98 at /drone/src/apps/files_sharing/lib/External/Manager.php#91
[Mon Jul 27 11:18:29 2020] 127.0.0.1:42174 [200]: /ocs/v1.php/apps/files_sharing/api/v1/remote_shares
    When requesting "/ocs/v1.php/apps/files_sharing/api/v1/remote_shares" with "GET" # FeatureContext::requestingWith()
    Then the OCS status code should be "997"                                         # FeatureContext::theOCSStatusCodeShouldBe()
      Notice: Trying to get property 'meta' of non-object in /drone/src/build/integration/features/bootstrap/BasicStructure.php line 153
[Mon Jul 27 11:18:29 2020] 127.0.0.1:42178 [200]: /ocs/v1.php/cloud/users/user0
[Mon Jul 27 11:18:29 2020] 127.0.0.1:42218 [404]: /ocs/v2.php/cloud/users/user0
[Mon Jul 27 11:18:29 2020] Login failed: 'user0' (Remote IP: '127.0.0.1')
[Mon Jul 27 11:18:29 2020] 127.0.0.1:42234 [401]: /remote.php/webdav/myFileToComment.txt
[Mon Jul 27 11:18:30 2020] 127.0.0.1:42242 [207]: /remote.php/dav/systemtags/
[Mon Jul 27 11:18:30 2020] Login failed: 'user0' (Remote IP: '127.0.0.1')
[Mon Jul 27 11:18:30 2020] 127.0.0.1:42264 [401]: /remote.php/webdav/myFileToTag.txt
[Mon Jul 27 11:18:30 2020] 127.0.0.1:42266 [404]: /remote.php/dav/addressbooks/users/admin/MyAddressbook
[Mon Jul 27 11:18:30 2020] 127.0.0.1:42294 [404]: /remote.php/dav/calendars/admin/MyCalendar

[MorrisJobke]

Tested and verified. Backport down to stable18 should work (the UserRemovedEvent event was added then)

[MorrisJobke]

Rebased and squashed

[MorrisJobke]

/backport to stable19

[MorrisJobke]

/backport to stable18

[MorrisJobke]

(the UserRemovedEvent event was added then)

#18350

[MorrisJobke]

There seems to be inconsistency for LDAP and other group backends. The listened old hook 'OC_User', 'post_removeFromGroup' is not emitted in the normal user/group backend since 16 at least?

In the DB backend it is only triggered on user deletion:

server/lib/private/User/User.php

Line 224 in cb05782

\OC_Hook::emit("OC_User", "post_removeFromGroup", ["uid" => $this->uid, "gid" => $groupId]);

[MorrisJobke]

The user removal from a group is a different event:

server/lib/private/Group/Group.php

Lines 222 to 227 in caff102

	$this->dispatcher->dispatch(IGroup::class . '::postRemoveUser', new GenericEvent($this, [
	'user' => $user,
	]));
	if ($this->emitter) {
	$this->emitter->emit('\OC\Group', 'postRemoveUser', [$this, $user]);
	}