Add response status to response object

[grantr]

The Elasticsearch 1.0 api is removing the ok attributes that have historically been used to detect successful responses. In several of these apis it is unclear how to detect a successful response from the response body.

I've resisted this so far, but I wonder if now might be the time to start returning a Response object instead of the raw response hash. My initial vision for this is as simple as possible:

class Response < Hash
  attr_accessor :status, :headers
end

This would allow api consumers to do things like:

response = docs.index(document)
if response.status != 201
   # fail
end

I'd avoid adding abstractions like success? unless there was a clear benefit from having them in the low level client. IMO those kinds of things should be at a higher level (even though we don't have a higher level yet). The Response object is necessary in the client because the information would otherwise be unretrievable.

/cc @github/search

[grantr]

While we may discover a way to detect success or failure from the response, I think the Elasticsearch devs feel that the response status is the canonical way to detect success or failure. See elastic/elasticsearch#4310

[grantr]

One counterpoint to this is our existing error handling in client.rb. That may already offer all the failure detection necessary.

[grantr]

Closing. I think the existing error handling is enough for now.