Fix nested serializer lookup

[stokarenko]

It fixes #30

undefined method 'load_all_lazy_relationships' for nil:NilClass exception is raising in specific env.

Lets fix two yet different causes of this:

1. host application uses customized serializers lookup (ActiveModelSerializers.config.serializer_lookup_chain), so ams_lazy_relationships should use the same lookup in order to get the same result;
2. in case of missed serializer, ActiveModelSerializers will inline nested object right into relationships as it is, so ams_lazy_relationships should keep rolling as well.

[Bajena]

Great work @stokarenko! Really impressive 🎩 Thanks for your time and high quality PR (nice descriptions and specs).

Btw. if I may ask - how did you get to know this gem and how are you using it?

[Bajena]

Unfortunately the master build has failed after merge (https://travis-ci.com/Bajena/ams_lazy_relationships/builds/142470412).
I suppose the older versions of active model serializers didn't support the serializer lookup chain feature.

If you still have some time (and patience :D) it'd be great if you took at them. If not I'll try fixing them (probably by disabling the new specs depending on the AMS version).

[stokarenko]

Hey @Bajena , nice to meet you! )

thanks a lot for your gem, it works like a charm )

if I may ask - how did you get to know this gem and how are you using it?

well, I'm trying to solve a massive N+1 issues within a large SOA project. We realized that active-model-serializer will fetch every association defined in serializer just for maintaining so-called relationships data. I.e. it fires a massive N+1 even without explicit includes.. o_O

So I started to develop my own solution for this, fixed N+1 at least for relationships data, started to think how to preload the things for explicit includes as well, came to laziness idea, then asked google is there is something like this - bingo )

If you still have some time (and patience :D) it'd be great if you took at them.

definitively I will do that on 6th Jun, right after vacation )

also I would like a push one more PR here, it will be a kind of dig but for nested associations, like

class SomeSerializer

  def some_attr
    lazy_dig(:organization, :logo)&.url
  end
end

it is already implemented, just need to tune a code a bit and write specs ) That is the last thing which turns your gem into a graceful rescue for my project )

[Bajena]

thanks a lot for your gem, it works like a charm )

Great to hear it. I had a very similar motivation for building it - we have a big API with lots of controllers loading nested data. It'd be really hard to specify proper Rails-style includes for all of them and maintain it. Also bullet gem wasn't very useful in our case.

definitively I will do that on 6th Jun, right after vacation )

🙇

also I would like a push one more PR here, it will be a kind of dig but for nested associations, like

Yeah, great idea. I already had a few cases when I needed to specify a lazy relationship only for fetching one attribute. Looking forward to seeing it!

[Bajena]

Btw @stokarenko you seem to be a very proficient developer. I'd be honored to grant you a maintainer privilege if you'd like. Would you be interested in that?

[stokarenko]

@Bajena

If you still have some time (and patience :D) it'd be great if you took at them.

definitively I will do that on 6th Jun, right after vacation )

Here we go! ) #43

lazy_dig is coming as well )

I'd be honored to grant you a maintainer privilege if you'd like. Would you be interested in that?

Sure thing, thank you! Lets do the great things together )

[Bajena]

Sure thing, thank you! Lets do the great things together )

Great! I've sent you an invitation to collaborate 🎉