Trouble accessing preferences after upgrade to Discourse 2.1.0.beta4

Bug
1

I just updated a site and now I’m not able to access /my/preferences/account. I get Server Error while trying to load /user-badges/jayp.json Error code: 504 Gateway Time-out

I tried safe mode, and removed the only non-standard plugin (retort).

Though other users do seem to be able to access their preferences. Many are complaining about group-based theme modifications not working, so it seems that there might be some problem with groups.

Other pages seem to load fine, however. I don’t see anything in the logs in the web interface and don’t see it in the rails logs either.

I cannot replicate this here or on another site that I upgraded today.

EDIT: My current guess is that the problem has to do with some custom badge. There are many of them, but they aren’t SQL badges, and now that I see that, the badge hypothesis doesn’t make much sense.

method=GET path=/user-badges/jayp.json format=json controller=UserBadgesController action=username status=200 duration=5684.38 view=0.10 db=5577.50 params=_=1533766004403&username=jayp database=default db_calls=111 redis=0.73 redis_calls=6 ip=107.206.118.212 username=jayp
2

Now that’s a lot of queries …

Reproduced and checked locally, UserSerializer is making tons of SQL queries on the fly when serializing user_badge.granted_by.

I think UserSerializer is an overkill for the badges page, and BasicUserSerializer should do?

 class DetailedUserBadgeSerializer < BasicUserBadgeSerializer
-  has_one :granted_by
+  has_one :granted_by, serializer: BasicUserSerializer

This cut down the number of queries from 81 to 8 locally for me.

Not too familiar with the badge-related pages, will dig a bit deeper to make sure this has no other side effects before submitting a PR.

5 Likes
3

Is that BasicUser as in Trust Level 1 ?

AFAIK, the number of Badges a New member can get is relatively few, and progressing to Basic member is not a high hurdle. Perhaps performance can be improved by taking New out of the query for those Badges that are impossible for a New member to get and running two queries instead?

4

Oh no, it’s actually Basic UserSerializer instead of BasicUser Serializer.

i.e. it contains much less information about a user, but should be enough for the badges page.

Sorry about the confusion!

2 Likes
5

Hmm. If you’ve replicated this, I’m going to charge this to a bug. It started when upgrading to beta 3, I believe.

1 Like
6

As far as I can see, the change is safe. Just submitted a PR:

https://github.com/discourse/discourse/pull/6266

Didn’t test with previous versions, but I have a feeling that this has been like this for a while. The number of queries will only increase dramatically if a user has badges granted by different staff members.

7 Likes
7

@sam, you appear to be the last to have touched this in a meaningful way.

Oooh! And I can confirm that it fixes the site where I was previously unable to open preferences or preferences/badges.

Thanks, @xrav3nz!

5 Likes