Infer serializer from collection name for empty results root

[mchitten]

Purpose

In the event that a collection object is empty and has a name, it's possible to determine the serializer from the name of the object. This may not always be the case -- this could raise NameError for a class that does not exist, or NoSerializerError if its matching serializer does not exist, in which case this falls back to the original name.underscore implementation.

Changes

Updates CollectionSerializer to try to determine serializer from object name.

Related GitHub issues

Possibly(?) a fix for #1745.

[mention-bot]

@mchitten, thanks for your PR! By analyzing the annotation information on this pull request, we identified @bf4, @Empact and @RomanKapitonov to be potential reviewers

[bf4]

Sort of wishing I had merged #1767 at this point...

[bf4]

this is really something like

Infer collection root preferably from the serializer for the collection name then the collection name, if a named collection

?

[bf4]

Seems you are wanting these in the global scope. Can we perhaps dynamically create and remove these classes or alias exiting ones? (.e.g SerializedResource = Post...)

[mchitten]

@bf4 Ready for another look when you get the chance

[mchitten]

Hey @bf4, any additional thoughts on this? Thanks!

[bf4]

1. I'd rather this be in a block so that we can also teardown the classes after defining them
2. I think we can consolidate the code here a little

def with_serializable_named_model(name)
  model = Class.new(::Model) do
    def self.name
      'SerializableResource'
    end
  end
  Object.const_set(:SerializableResource, model)
  serializer = Class.new(ActiveModel::Serializer) do
    def json_key
      name
    end
  end
  Object.const_set(:SerializableResourceSerializer, serializer)
  yield model
ensure
  Object.send(:remove_const, :SerializableResource)
  Object.send(:remove_const, :SerializableResourceSerializer)
end

then

def test_json_key_with_resource_with_name_and_serializer
  with_serializable_named_collection('resources') do |model|
     serializer_instance = collection_serializer.new([model])
     assert_equal 'resources', serializer_instance.json_key
  end
end

[bf4]

(would also be good to note for the reviewer how the test would fail before the code changes)

[bf4]

Not sure how important to your use case, but note that in the test I changed

- collection_serializer.new(model)
+ collection_serializer.new([model])

since the collection serializer should take in an array of models, or at least something enumerable. Was that a bug in the test or in your implementation?

[NullVoxPopuli]

needs rebase.

@bf4 can you summarize all your comments so @mchitten can finish this? :-)

[dyoganand]

Will this be merged??

[bf4]

@dyoganand This needed some revisions. Would you be interested in taking it on?

[bf4]

same issue: #2087 (comment)

[IzumiSy]

When is this PR going to be merged? I am being bothered exactly at the moment by the bug which this PR potentially fixes up.

[samuelpismel]

2 years... Two years! And this isn't merged...

[NullVoxPopuli]

@samuelpismel at this point, if you want newish support / a library that easier to maintain, I'd use http://jsonapi-rb.org/ (by @beauby who also is a member of @rails-api/ams )

if you don't have a jsonapi style api, jbuilder is probably good enough.

This project has gone through so many rewrites...
The master branch has also been cleared out "in prep" for the next rewrite -- so this PR would need to target the 0.10.x branch.

:-\

Apologies for the circumstances. :(

Please see Status of AMS

[samuelpismel]

Thanks man, you are correct, sorry about that.