Refactor UserController#search_users

[blowmage]

Move the SQL generation behind an intention revealing name, add tests.

[eviltrout]

Love it. Any idea why it doesn't merge cleanly? Also would you mind filling out our CLA: http://www.discourse.org/cla

@SamSaffron this approach keeps the SQL but isolates it from the controller. I vastly prefer it but would be more comfortable with your approval before merging.

[blowmage]

@eviltrout I created the branch around nine hours ago. If it doesn't merge then you guys must have been busy in that time. :) I'll update on master and re-push.

[blowmage]

FWIW, an accompanying blog explaining the thought behind this change here.

[eviltrout]

Just wanted to say thanks for an awesome blog post explaining why you did it. It's one thing to link to some code on twitter, it's another to submit a patch to fix it and a detailed blog post of why. I am super impressed, and will happily merge this once @SamSaffron has a chance to review.

[ZogStriP]

👍 for the awesome blog post!

[nlalonde]

Great changes, thanks so much, blowmage! One minor comment is that UserSearch is a service class, not really a model. It belongs in lib, imho.

[steveklabnik]

One minor comment is that UserSearch is a service class, not really a model. It belongs in lib, imho.

It models searching for a User. Sounds like a model to me.

(Regardless, I think service classes belong in app/models too: like Mike said in his blog post, lib is for things that could be used on other projects.)

[blowmage]

A word on UserSearch. The reason it is a class and not a module, even though it is never instantiated, is because I expected to instantiate it as part of this refactor. Ideally, the UserSearch.search implementation would have instantiated a UserSearch object and looked like so:

def self.search term, topic_id = nil
  UserSearch.new(term, topic_id).search_with_sql
end

That would allow me to add new capabilities in a non-destructive way. So if a pure arel search was added, it could look like the following:

def self.search term, topic_id = nil
  UserSearch.new(term, topic_id).search_with_arel
end

That said, I got sleepy and never got that far. I'm still not sure if an arel/ActiveRecord::Relation implementation is wanted, so I figured I'd submit this anyway and see what happened. I suppose this info would be better in a commit message than a comment on the pull request, but there you go.

¯_(ツ)_/¯

[bbonamin]

@blowmage seems like a good choice. I was just about to ask why you decided for a class instead of a module. Your last comment reminded me of this codeclimate blog post http://blog.codeclimate.com/blog/2012/11/14/why-ruby-class-methods-resist-refactoring/

[SamSaffron]

I am totally fine with this, more test, more readable code, big wins for Discourse

[eviltrout]

❤️❤️❤️