Port Taxonomy Autotagger to D8

Thanks Alvaro, I'll take a look at it as soon as I can.

I notice you're at DrupalCon Dublin - I too am at DrupalCon Dublin, and should be at the social this evening - look out for me, I'm wearing a white t-shirt with red stars on.

I tested the D8 version (straight clone from github, not the patch here) and it is working. I need to do some further work on the module for a client which will hopefully be accepted into the module itself so it would be great if you could commit this so I could use the 8.x branch as a base rather than the github clone.

As I've been working on the two features I need for the client, I've been fixing problems I found in the existing code. Some of them are included in the patch I already submitted for #2854724: Allow scanning on fields from referenced entities and some in the patch I've not quite finished. I think that having them done in those patches is going to make it less clear what I'm changing, though. So, once I've got this bit I'm working on done, I'm going to pull out all the changes that were fixing the port and submit them as a patch on this ticket. That will leave the other two patches restricted to just the features they are adding.

I've made the edits to alvar0hurtad0's port that are just fixing things and not adding any new features. I am attaching a complete patch with both his port and my changes as well as an interdiff so you can see what parts I changed.

I have not tested the bulk update feature and I believe the checkbox is done wrong but I have not fixed that, yet. That could be done in a follow up issue if needed, if you are able to get to this before I have a look at it.

Standardized the issue title.

No, I won't be be in Seville. I haven't used this on D7 so all I know is it had another module dependency before but I haven't seen where the code is split. It's such a small module and works as is so I'm not sure why it's needed but I'll respect the wishes of the maintainer. I don't want to be duplicating work you are doing but I do need to get this working for the client. Assuming you are talking about "Drupal Developer Days Seville 2017", that is still a month away. Were you planning on working on it before then?

I'm in an odd place because your port plus my patches work to satisfy the client's needs for the moment. I don't really see a need to split the module apart as it isn't that big to begin with. While it would be nice to have something that satisfies the maintainer's requirements for committing, I can't put more client time into it right now so am just in limbo until I get further instruction or something happens on your end.

Adding a new patch that removes some whitespace because it was causing issues with the patches in my other two issues. There is no difference between this and the previous patch other than removing whitespace from one blank line. I realize that we're talking about going in a completely different direction but, in the mean time, I need this so composer doesn't choke. :)

On further testing for the client, I found that there is a bug in the original port that doesn't account for nodes which haven't been set up for autotag. On save, it crashes because there is no source/destination set. This patch adds in code to address that.

FYI, I made this sandbox 2 years ago because it was getting unwieldy trying to handle all the patches in composer: https://www.drupal.org/sandbox/michelle/2882893 . I no longer work on the client it was made for nor do I use the module myself. Ideally, that code should come back here as a D8 branch. If someone wants to take that on, feel free to use the code from the sandbox (which was based on code from this issue, anyway, and patched). Here is the process to request maintainership of this module: https://www.drupal.org/node/251466 . If someone does this, please comment on this issue so I know and I will direct the sandbox module users over here.

@Michelle I did request maintainership in #3307075: Offering to maintain Taxonomy Autotagger but that was denied. To be fair, this project has been marked as obsolete. I'd be open to updating your code to be ready for Drupal 9 / 10 and releasing it under a new namespace.

@mandclu You are welcome to my code. It was done for a client project that I no longer am involved with and I forgot it was even there. As for where to release it, I think it would be good to resolve the maintainership of this module rather than make a totally new one but that's up to you.