Getting d6_field_group plugin must define the source_module property Error When Using migrate-upgrade

The reason is the change in the migrate api described here: https://www.drupal.org/node/2911881

I added a patch to address this issue.

Works to remove the error.
Drupal 8.5.0
Field Group 8.x-3.0-beta1

I was having the same issue, Drupal 8.5.0. Patch in #7 resolved it for me.
Thank you.

The patch in #7 also worked for me. Thank you so much for identifying it so quickly!

Thanks, that's a quickfix

the patch in 7 against latest dev doesn't change a thing.

Having the same problem - "Resolve all issues below to continue the upgrade. The d7_field_group plugin must define the source_module property."

The patch changes lines in a comment - how can that fix it???! :o)

@Jon Pollard, thats because this comment is an annoation. That means, that this is actual metadata that the plugin-system reads and interpretes. For more details see: https://www.drupal.org/docs/8/api/plugin-api/annotations-based-plugins

Thanks @Nebel 54 - that's an unusual use of comments! But hey, who am I to question how these things work?

Has something changed since the patch rolled against 8.x-3.x to stop this working? My d8 site that I'm trying to migrate to is 8.5.4, should I be using 8.6? Would that help?

@Nebel54
Excuse me my understanding of programming is really basic maybe I should not go into this D6-D8 migration thing... :-/ it's supposed to save me time - I have like 500 articles in the site I'm trying to upgrade.
I've tried to apply the patch#7 but still get the error mentioned above.
Drupal 8.5.4
Field Group 8.x-3.0-beta1
PHP 7.0.30

In modules / field_group / contrib / field_group_migrate / src / Plugin / migrate / source / d6 / FieldGroup.php
I've not uncommented and simply replaced

/**
* Drupal 6 field_group source.
*
* @MigrateSource(
* id = "d6_field_group"
* )
*/

WITH

/**Drupal 6 field_group source.
*
* @MigrateSource(
* id = "d6_field_group",
* source_module = "field_group",
* destination_module = "field_group"
* )
*/

is that it...?

Thanks for your understanding & time

Thx for the patch + reviewing it. I have no errors, so committed to dev

@zuuperman does the community consider the patch fixed the problem for good ?
I can't mp anyone here... clueless

@Jude P: Yes that should be enough. Did you clear the caches with drush cr after applying the patch?

@Nebel54 thanks yes I did ! I cleared the cache through PHPMyAdmin (Truncate command) - apparently it should do the trick...but it doesn't. Still the same error message

@Nebel54 I don't use Drush I've cleared the cache through PHPMyAdmin (Truncate all cache_ tables), also tried updating the database (/update.php) like I read somewhere. is it not enough ?

@Nebel54 sorry to bother you, I've posted in the forum but no one cares.. I've tried rebuilding the cache in nearly every possible way and the error remains...

Sorting this out would probably save me a lot of time. Provided someone helps.

I am fixing something of this on this issue

Trying to install this patch gets me - the "error: contrib/field_group_migrate/src/Plugin/migrate/source/d6/FieldGroup.php: No such file or directory"

I don't have Field Group in D6, so I'm a little confused how this patch is supposed to help migrate it?

After applying patch #7 still, I am still getting an error "The d6_field_group plugin must define the source_module property".

I am migrating content from Drupal 7.61 to Drupal 8.64. This patch not worked for me.

Issue of "The d6_field_group plugin must define the source_module property." Remains in Drupal 8.6.9.

My installation:
Drupal 8.6.9
Field group 8.3.x-dev

Patch in issue #3002645 as stated by @edysmp fixed this error