Class: Attune::Gzip

Inherits:
Faraday::Middleware
  • Object
show all
Defined in:
lib/attune/gzip.rb

Overview

Some code taken from a yet to be released version of faraday-middleware

Constant Summary collapse

CONTENT_TYPE = 
'Content-Type'.freeze
CONTENT_ENCODING = 
'Content-Encoding'.freeze
MIME_TYPE = 
'application/json'.freeze
ENCODING_TYPE = 
'gzip'.freeze
ACCEPT_ENCODING = 
'Accept-Encoding'.freeze
CONTENT_LENGTH = 
'Content-Length'.freeze
SUPPORTED_ENCODINGS = 
'gzip,deflate'.freeze
RUBY_ENCODING = 
'1.9'.respond_to?(:force_encoding)

Instance Method Summary collapse

Instance Method Details

#call(env) ⇒ Object 



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# File 'lib/attune/gzip.rb', line 15

def call(env)
  if has_body?(env) && is_json?(env)
    wio = StringIO.new("w")
    w_gz = Zlib::GzipWriter.new(wio)
    w_gz.write env[:body]
    w_gz.close
    env[:body] = wio.string
    env[:request_headers][CONTENT_ENCODING] = ENCODING_TYPE
  end
  env[:request_headers][ACCEPT_ENCODING] ||= SUPPORTED_ENCODINGS
  @app.call(env).on_complete do |env|
    case env[:response_headers][CONTENT_ENCODING]
    when 'gzip'
      reset_body(env, &method(:uncompress_gzip))
    when 'deflate'
      reset_body(env, &method(:inflate))
    end
  end
end

#has_body?(env) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/attune/gzip.rb', line 37

def has_body?(env)
  body = env[:body] and !(body.respond_to?(:to_str) and body.empty?)
end

#inflate(body) ⇒ Object 



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# File 'lib/attune/gzip.rb', line 56

def inflate(body)
  Zlib::Inflate.inflate(body)
end

#is_json?(env) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/attune/gzip.rb', line 34

def is_json?(env)
  env[:request_headers][CONTENT_TYPE] == MIME_TYPE
end

#reset_body(env) ⇒ Object 



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# File 'lib/attune/gzip.rb', line 41

def reset_body(env)
  env[:body] = yield(env[:body])
  env[:response_headers].delete(CONTENT_ENCODING)
  env[:response_headers][CONTENT_LENGTH] = env[:body].length
end

#uncompress_gzip(body) ⇒ Object 



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# File 'lib/attune/gzip.rb', line 47

def uncompress_gzip(body)
  io = StringIO.new(body)
  gzip_reader = if RUBY_ENCODING
    Zlib::GzipReader.new(io, :encoding => 'ASCII-8BIT')
  else
    Zlib::GzipReader.new(io)
  end
  gzip_reader.read
end