Module: Async::HTTP::Cache::Body

Defined in:
lib/async/http/cache/body.rb

Constant Summary collapse

TRAILERS = 
'trailers'
ETAG = 
'etag'

Class Method Summary collapse

Class Method Details

.wrap(response, &block) ⇒ Object 



34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
 
# File 'lib/async/http/cache/body.rb', line 34

def self.wrap(response, &block)
  if body = response.body
    if body.empty?
      # A body that is empty? at the outset, is immutable. This generally only applies to HEAD requests.
      yield response, body
    else
      # Insert a rewindable body so that we can cache the response body:
      rewindable = ::Protocol::HTTP::Body::Rewindable.wrap(response)
      
      unless response.headers.include?(ETAG)
        # Compute a digest and add it to the response headers:
        ::Protocol::HTTP::Body::Digestable.wrap(response) do |wrapper|
          response.headers.add(ETAG, wrapper.etag)
        end
        
        # Ensure the etag is listed as a trailer:
        response.headers.add(TRAILERS, ETAG)
      end
      
      # Wrap the response with the callback:
      ::Protocol::HTTP::Body::Completable.wrap(response) do |error|
        if error
          Async.logger.error(self) {error}
        else
          yield response, rewindable.buffered
        end
      end
    end
  else
    yield response, nil
  end
  
  return response
end