undefined method `embed'

[tommyblue]

I'm using the 0.10.0.rc1 version because 0.9.x doesn't work, but with this definition of the serializer:

class Api::V1::ItinerarySerializer < ActiveModel::Serializer
  attributes :id, :title

  embed :ids, include: true
  has_many :pois, serializer: Api::V1::PoiSerializer
end

I get this error:

NoMethodError (undefined method `embed' for Api::V1::ItinerarySerializer:Class):
  app/serializers/api/v1/itinerary_serializer.rb:4:in `<class:ItinerarySerializer>'
  app/serializers/api/v1/itinerary_serializer.rb:1:in `<top (required)>'
  app/controllers/api/v1/itineraries_controller.rb:29:in `update'

Embed is deprecated? How can I generate the "old" JSON including associated objects, like this:

{
  "itinerary": {
    "poi_ids": [1,4,5]
  },
  { "pois": [
    // POI serialized objects
  ]}
}

[groyoh]

I'm afraid that is not currently possible with 0.10. @joaomdmoura is this a planned feature for 0.10?
In the meantime, you could workaround it by creating your own adapter based on the json adapter. If you need some help with that let me know.

[tommyblue]

ok, thanks.
Shouldn't this an important option? I have an habtm association and embedding object is a good way to avoid data replication inside the single json response or avoiding multiple requests (one for each id).
Isn't it?

[joaomdmoura]

Hey @tommyblue, indeed, @groyoh is right!

Its possible to accomplish something close to it by using JSON-API, but would be a different implementation and not the '"old" JSON'.

btw why not use only:

 has_many :pois, serializer: Api::V1::PoiSerializer

This will return the serialized objects, isn't waht you need? You can map the ids if you want to, on a virtual attribute:

class Api::V1::ItinerarySerializer < ActiveModel::Serializer
  attributes :id, :title, : poi_ids
  has_many :pois, serializer: Api::V1::PoiSerializer

  def poi_ids
    object.pois.map {|p| p.id}
  end
end

[tommyblue]

If I'm not wrong, your solution puts the serialized POI objects inside their Itinerary "fathers". This means that there will be a lot of replicated POI objects inside different itineraries. This is not a problem with few objects but with a lot of objects is a lot of useless weigth into the JSON

[bf4]

@tommyblue Which adapter are you using? Json or JsonApi? You might want to subclass the adapter you're using to extend it.

[tommyblue]

@bf4 I could, but I'd like to understand from @joaomdmoura if I'm saying something wrong stating that the use of embed :ids, include: true is preferable when having a HABTM association with a lot of records since it can reduce the weight of the response.
I don't know the background discussion which led to removing embed, but I think it's useful so I'd like to understand why isn't present any more :)

thanks!

[joaomdmoura]

@tommyblue indeed I didn't realised the whole scenario. It makes sense.
Actually we haven't decided to remove embed, we just haven't implemented or discussed about it yet. 😄

The good news is that I'm willing to review a PR implementing it, but the bad one is that I'm busy into some other new features, so we can't work on this right now, but we might do it in a near future!! 😄 Meanwhile @kurko do you have any thoughts about it?

[tommyblue]

thanks @joaomdmoura

[NullVoxPopuli]

side loading is the preferred method of retrieving data for ember.
it reduces redundancy when nested models would otherwise reference the same model.

for example, if your json references "tag" objects, you don't want to include the same tag data twice, so you just make an id reference.

[ZackMattor]

👍 I also need this functionality... I'll probably have to roll back to 0.9 for now.