Module: Webmachine::Decision::Helpers

Included in:
FSM
Defined in:
lib/webmachine/decision/helpers.rb

Overview

Methods that assist the Decision Flow.

Constant Summary

QUOTED =
Pattern for quoted headers 
/^"(.*)"$/

Instance Method Summary (collapse)

Instance Method Details

- (Object) accept_helper

Assists in receiving request bodies 


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# File 'lib/webmachine/decision/helpers.rb', line 70

def accept_helper
  content_type = MediaType.parse(request.content_type || 'application/octet-stream')
  acceptable = resource.content_types_accepted.find {|ct, _| content_type.match?(ct) }
  if acceptable
    resource.send(acceptable.last)
  else
    415
  end
end

- (Object) add_caching_headers

Adds caching-related headers to the response. 


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# File 'lib/webmachine/decision/helpers.rb', line 91

def add_caching_headers
  if etag = resource.generate_etag
    response.headers['ETag'] = ensure_quoted_header(etag)
  end
  if expires = resource.expires
    response.headers['Expires'] = expires.httpdate
  end
  if modified = resource.last_modified
    response.headers['Last-Modified'] = modified.httpdate
  end
end

- (Object) encode_body

Encodes the body in the selected charset and encoding. 


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# File 'lib/webmachine/decision/helpers.rb', line 23

def encode_body
  body = response.body
  chosen_charset = metadata['Charset']
  chosen_encoding = metadata['Content-Encoding']
  charsetter = resource.charsets_provided && resource.charsets_provided.find {|c,_| c == chosen_charset }.last || :charset_nop
  encoder = resource.encodings_provided[chosen_encoding]
  response.body = case body
                  when String # 1.8 treats Strings as Enumerable
                    resource.send(encoder, resource.send(charsetter, body))
                  when Fiber
                    FiberEncoder.new(resource, encoder, charsetter, body)
                  when Enumerable
                    EnumerableEncoder.new(resource, encoder, charsetter, body)
                  else
                    if body.respond_to?(:call)
                      CallableEncoder.new(resource, encoder, charsetter, body)
                    else
                      resource.send(encoder, resource.send(charsetter, body))
                    end
                  end
  if String === response.body
    response.headers['Content-Length'] = response.body.respond_to?(:bytesize) ? response.body.bytesize.to_s : response.body.length.to_s
  else
    response.headers.delete 'Content-Length'
    response.headers['Transfer-Encoding'] = 'chunked'
  end
end

- (Object) encode_body_if_set

If the response body exists, encode it.

See Also:



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# File 'lib/webmachine/decision/helpers.rb', line 18

def encode_body_if_set
  encode_body if has_response_body?
end

- (Object) ensure_quoted_header(value)

Ensures that a header is quoted (like ETag) 


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# File 'lib/webmachine/decision/helpers.rb', line 52

def ensure_quoted_header(value)
  if value =~ QUOTED
    value
  else
    '"' << value << '"'
  end
end

- (Boolean) has_response_body?

Determines if the response has a body/entity set.

Returns:

  • (Boolean) 


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# File 'lib/webmachine/decision/helpers.rb', line 12

def has_response_body?
  !response.body.nil? && !response.body.empty?
end

- (Object) unquote_header(value)

Unquotes request headers (like ETag) 


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# File 'lib/webmachine/decision/helpers.rb', line 61

def unquote_header(value)
  if value =~ QUOTED
    $1
  else
    value
  end
end

- (Object) variances

Computes the entries for the 'Vary' response header 


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# File 'lib/webmachine/decision/helpers.rb', line 81

def variances
  resource.variances.tap do |v|
    v.unshift "Accept-Language" if resource.languages_provided.size > 1
    v.unshift "Accept-Charset" if resource.charsets_provided && resource.charsets_provided.size > 1
    v.unshift "Accept-Encoding" if resource.encodings_provided.size > 1
    v.unshift "Accept" if resource.content_types_provided.size > 1
  end
end