Abstract

The identification of resources on the Web by a Uniform Resource Identifier (URI) alone may not be sufficient, as other factors such as HTTP content negotiation might come into play. This issue is particularly significant for quality assurance testing, conformance claims, and reporting languages like the W3C Evaluation And Report Language (EARL). This document provides a representation of the HTTP vocabulary in the Resource Description Framework (RDF), to allow quality assurance tools to record the HTTP headers that have been exchanged between a client and a server. The RDF terms defined by this document represent the core HTTP specification defined by RFC 2616, as well as additional HTTP headers registered by the Internet Assigned Numbers Authority (IANA). These terms can also be used to record HTTPS exchanges.

This document defines a representation of the Hypertext Transfer Protocol (HTTP) using the Resource Description Framework (RDF). It defines a collection of RDF classes and properties that represent the HTTP vocabulary as defined by the HTTP specification [RFC2616]. These RDF terms can be used to record HTTP or secure HTTP request and response messages in RDF format, such as by automated Web accessibility evaluation tools that want to describe Web resources, including the various headers exchanged between the client and server during content negotiation. More usage examples for these terms are described in section 1.2 Use Cases.

Note: The version 1.0 specifies the version of the HTTP Vocabulary in RDF document and not the version of HTTP. The vocabulary defined in this specification is usable for HTTP versions up to 1.1.

This document is not intended to be a clarification or extension of the different concepts of the HTTP specification. The HTTP specification is defined by a series of Request for Comments (RFC) publications and other documentation, including [RFC 2616] and [RFC 4229]. These are listed in Appendix C: References.

Additionally this document assumes the following background knowledge:

• Basic knowledge of the Extensible Markup Language (XML) [XML] and its associated technologies.
• Basic knowledge about the Semantic Web and RDF. For references, consult [RDF], [RDFS], [RDF-PRIMER] and [OWL].

The terms defined by this document can be used as part of the W3C Evaluation And Report Language (EARL) and in other contexts too. Developer Guide for Evaluation and Report Language (EARL) 1.0 explains how to implement and use EARL, including conformance requirements for software tools.

By default, the vocabulary introduced by this document uses names starting with upper-case letters for classes and names starting with lower-case letters for properties. The keywords must, required, recommended, should, may, and optional are used in accordance with [RFC2119].

The RDF representation of the HTTP vocabulary defined by this document uses the namespace http://www.w3.org/2011/http#. The prefix http is used throughout this document to denote this namespace. Table 1 presents the namespaces used by this document. The prefix notation presents the typical conventions used in the Web and in this document to denote a given namespace, and can be freely modified. Table 2 presents additional RDF data used by this document.

The following (non-exhaustive) list of use cases aims to highlight some of the different usages of the terms provided by this document:

When Web resources are tested, for example for accessibility or other quality assurance testing, it may be significant to record the exact headers exchanged between the server and the client during the testing. Without a record of the exchanged headers, it may not be possible to re-identify the exact resource (or representation of the resource) that has been tested. The terms provided by this document allow quality assurance tools to record the HTTP exchange between a client and a server, for example to record the POST parameters or the headers used during content negotiation. The terms provided by this document can be used in combination with the W3C Evaluation And Report Language (EARL) [EARL].

Conformance claims that are made about a Web resource or group of Web resource, are sometimes only applicable under certain constraints. For example, conformance of a Web site to the W3C Web Content Accessibility Guidelines (WCAG) [WCAG], may only be applicable for a certain language of the Web site that is using language negotiation. When providing machine-readable conformance claims, for example using the W3C Protocol for Describing Web Resources (POWDER): Description Resources [POWDER-DR], it is important to precise any such constraints that may apply.

Web applications using client-side scripting such as AJAX may exchange additional HTTP messages with the server without using a different URI. In order to debug such Web applications, it must be possible to reconstruct the exact history of the states through which the Web application passed. Web authoring tools that are designed to develop and debug Web applications could use the terms provided by this document to record the exact HTTP messages exchanged between a client and a server. This information could be provided to the developer as a log to help debug errors in the Web application.

When indexing RDF information resources that are available through the HTTP protocol (also called "scuttering" in Semantic Web parlance), it is often useful to record information about the HTTP request and response messages that were exchanged, along with the data for later use. In some instances, different representations of the RDF information may be retrieved from the server depending on the HTTP headers and parameters exchanged. The terms provided by this document can be used to supplement the collected data with the HTTP messages as part of a comprehensive indexing repository.

There are also notable schema limitations in regard to security and privacy since the content recorded by this vocabulary could potentially contain sensitive information, for example authentication information in HTTP headers or other information (login user name, passwords, and so on) within the body of the message. Since the schema of this document is limited to terms defined by the HTTP vocabulary, security and privacy considerations need to be made at the application level. For example, certain parts of the data may be restricted to appropriate user permissions or obfuscated.

This section defines RDF classes for the HTTP 1.1 specification according to [RFC2616].

A connection that is used for the HTTP transfer.

• Domain of:
  • http:connectionAuthority
  • http:requests
• Range of: none

<http:Connection rdf:ID="conn">
 <http:connectionAuthority>www.example.org:80</http:connectionAuthority>
 <http:requests rdf:parseType="Collection">
 <http:Request rdf:ID="req0"/>
 <http:Request rdf:ID="req1"/>
 </http:requests>
</http:Connection>

An HTTP message.

• Domain of:
  • http:httpVersion
  • http:headers
  • http:body
• Range of: none

It may be appropriate to provide additional information about the Message by using the following from external vocabularies:

dct:date 👁 external link

Message date (see the usage of this property in requests and responses).

<http:Message rdf:ID="mess0">
 <http:httpVersion>1.1</http:httpVersion>
 <dct:date>2007-09-13</dct:date>
 <http:headers rdf:parseType="Collection">
 <http:MessageHeader rdf:ID="mh0"/>
 <http:MessageHeader rdf:ID="mh1"/>
 </http:headers>
 <http:body>
 <cnt:Content rdf:ID="cont0"/>
 </http:body>
</http:Message>

There are two subclasses from the http:Message class: http:Request and http:Response.

An HTTP request. The http:Request class is a subclass of the http:Message class.

• Domain of:
  • http:methodName
  • http:mthd
  • http:requestURI
  • http:resp
• Range of: none

when used in a Request resource represents the date the request was sent by the client.

<http:Request rdf:ID="reqs0">
 <http:absolutePath>/</http:absolutePath>
 <http:methodName>GET</http:methodName>
 <http:mthd rdf:resource="http://www.w3.org/2011/http-methods#GET"/>
 <http:resp rdf:resource="#resp0"/>
 <dct:date>2007-09-13</dct:date>
 <http:httpVersion>1.1</http:httpVersion>
 <http:headers rdf:parseType="Collection">
 <http:MessageHeader rdf:about="#mh0"/>
 <http:MessageHeader rdf:about="#mh1"/>
 </http:headers>
</http:Request>

An HTTP response. The http:Response class is a subclass of the http:Message class.

• Domain of:
  • http:statusCodeValue
  • http:sc
  • http:reasonPhrase
• Range of:
  • http:resp

when used in a Response resource represents the date the response was received by the client.

<http:Response rdf:ID="resp0">
 <http:httpVersion>1.1</http:httpVersion>
 <dct:date>2008-01-11</dct:date>
 <http:statusCodeValue>200</http:statusCodeValue>
 <http:sc rdf:resource="http://www.w3.org/2011/http-statusCodes#OK"/>
 <http:headers rdf:parseType="Collection">
 <http:MessageHeader rdf:about="#mh2"/>
 <http:MessageHeader rdf:about="#mh3"/>
 </http:headers>
 <http:body>
 <cnt:Content rdf:ID="cont0"/>
 </http:body>
</http:Response>

A header in an HTTP message.

• Domain of:
  • http:fieldName
  • http:hdrName
  • http:fieldValue
  • http:headerElements
• Range of: none

<http:MessageHeader rdf:ID="mh0">
 <http:fieldValue>text/html, image/png, image/gif;q=0.8</http:fieldValue>
 <http:fieldName>Accept</http:fieldName>
 <http:hdrName rdf:resource="http://www.w3.org/2011/http-headers#accept"/>
 <http:headerElements rdf:parseType="Collection">
 <http:HeaderElement rdf:about="#he0"/>
 <http:HeaderElement rdf:about="#he1"/>
 <http:HeaderElement rdf:about="#he2"/>
 </http:headerElements>
</http:MessageHeader>

A general header in an HTTP message. The http:GeneralHeader class is a subclass of the http:MessageHeader class.

• Domain of: none
• Range of: none

<http:GeneralHeader rdf:ID="gh0">
 <http:fieldValue>chunked</http:fieldValue>
 <http:fieldName>Transfer-Encoding</http:fieldName>
 <http:hdrName rdf:resource="http://www.w3.org/2011/http-headers#transfer-encoding"/>
</http:GeneralHeader>

A header in an HTTP request message. The http:RequestHeader class is a subclass of the http:MessageHeader class.

• Domain of: none
• Range of: none

<http:RequestHeader rdf:ID="rh0">
 <http:fieldValue>text/html</http:fieldValue>
 <http:fieldName>Accept</http:fieldName>
 <http:hdrName rdf:resource="http://www.w3.org/2011/http-headers#accept"/>
</http:RequestHeader>

A header in an HTTP response message. The http:ResponseHeader class is a subclass of the http:MessageHeader class.

• Domain of: none
• Range of: none

<http:ResponseHeader rdf:ID="reh0">
 <http:fieldValue>bytes</http:fieldValue>
 <http:fieldName>Accept-Ranges</http:fieldName>
 <http:hdrName rdf:resource="http://www.w3.org/2011/http-headers#accept-ranges"/>
</http:ResponseHeader>

An entity header in an HTTP message. The http:EntityHeader class is a subclass of the http:MessageHeader class.

• Domain of: none
• Range of: none

<http:EntityHeader rdf:ID="eh0">
 <http:fieldValue>3495</http:fieldValue>
 <http:fieldName>Content-Length</http:fieldName>
 <http:hdrName rdf:resource="http://www.w3.org/2011/http-headers#content-length"/>
</http:EntityHeader>

An element in a header value, if a Message Header value can be decomposed into several parts.

• Domain of:
  • http:elementName
  • http:elementValue
  • http:params
• Range of: none

<http:HeaderElement rdf:ID="he0">
 <http:elementName>image/gif</http:elementName>
 <http:params rdf:parseType="Collection">
 <http:Parameter rdf:ID="param0"/>
 </http:params>
</http:HeaderElement>

A parameter in a Header Element.

• Domain of:
  • http:paramName
  • http:paramValue
• Range of: none

<http:Parameter rdf:ID="param0">
 <http:paramName>q</http:paramName>
 <http:paramValue>0.8</http:paramValue>
</http:Parameter>

The HTTP 1.1 specification defines eight methods: OPTIONS, GET, HEAD, POST, PUT, DELETE, TRACE, CONNECT. Additionally [RFC5789] defines the PATCH method. The RDF graph available in RDF/XML at http://www.w3.org/2011/http-methods provides http:Method resources for each of these to be used as objects for the http:mthd property. A resource of type http:Method represents the name of a method used with HTTP.

• Domain of: none
• Range of:
  • http:mthd

[HTTP Status Codes] is a registry for status codes too be used in HTTP. The RDF graph available in RDF/XML at http://www.w3.org/2011/http-statusCodes provides http:StatusCode resources for each of these to be used as objects for the http:sc property. A resource of type http:StatusCode represents a status code.

• Domain of:
  • http:statusCodeNumber
• Range of:
  • http:sc

Header names to be used in HTTP are registered by the IANA (see [RFC4229], [Permanent Headers], and [Provisional Headers]). The RDF graph available in RDF/XML at http://www.w3.org/2011/http-headers provides http:HeaderName resources for each of these to be used as objects for the http:hdrName property. A resource of type http:HeaderName represents the name of a header used with HTTP.

Properties defined by this document:

• Domain of: none
• Range of:
  • http:hdrName

This section defines RDF properties for the HTTP 1.1 specification according to [RFC2616].

This property relates a resource object of the type Message to a resource object of the type cnt:Content or a subclass thereof to be the Message's entity body as defined in [RFC2616]. HTTP bodies are series of bytes. Thus for the resource object, it is appropriate to point to a cnt:ContentAsBase64 resource (see [Content-in-RDF] for more information on content representations using the Resource Desription Framework (RDF)).

Domain:

http:Message

Range:

cnt:ContentAsBase64 👁 external link

<http:Message rdf:ID="mess0">
 <http:body>
 <cnt:ContentAsBase64 rdf:ID="cont0-bin"/>
 </http:body>
 </http:Message>

Connection authority: server, host and port for a connection.

Domain:

http:Connection

Range:

Literal

Header element name (Literal).

Domain:

http:HeaderElement

Range:

Literal

Header element value (Literal).

Domain:

http:HeaderElement

Range:

Literal

Header name (Literal).

Domain:

http:MessageHeader

Range:

Literal

Header value (Literal).

Domain:

http:MessageHeader

Range:

Literal

HTTP headers sent with the message.

Domain:

http:Message

Range:

unspecified

Header value elements.

Domain:

http:MessageHeader

Range:

unspecified

This property relates a resource of type http:MessageHeader to a resource of type http:HeaderName.

Domain:

http:MessageHeader

Range:

http:HeaderName

Property representing the HTTP version number as a Literal (the format is 'digit.digit').

Domain:

http:Message

Range:

Literal

HTTP method.

Domain:

http:Request

Range:

http:Method

HTTP method name (Literal).

Domain:

http:Request

Range:

Literal

Header element parameters.

Domain:

http:HeaderElement

Range:

unspecified

Parameter name.

Domain:

http:Parameter

Range:

Literal

Parameter value.

Domain:

http:Parameter

Range:

Literal

Reason phrase sent by the server.

Domain:

http:Response

Range:

Literal

HTTP requests sent via the connection.

Domain:

http:Connection

Range:

unspecified

The request URI as specified in section 5.1.2 of [RFC2616]. This vocabulary defines the following sub-properties:

• http:absoluteURI
• http:absolutePath
• http:authority

Domain:

http:Request

Range:

Literal

<http:Request>
 <http:methodName>OPTIONS</http:methodName>
 <http:requestURI>*</http:requestURI>
 ...
</http:Request>

Request URI that is an absolute URI.

<http:Request>
 <http:methodName>GET</http:methodName>
 <http:absoluteURI>http://www.example.org:80/foo/bar</http:absoluteURI>
 ...
</http:Request>

Request URI that is an absolute path.

<http:Request>
 <http:methodName>GET</http:methodName>
 <http:absolutePath>/foo/bar</http:absolutePath>
 ...
</http:Request>

Request URI that is an authority.

<http:Request>
 <http:methodName>CONNECT</http:methodName>
 <http:authority>www.example.org:80</http:authority>
 ...
</http:Request>

This property relates a resource of type http:Request to a resource of type http:Response.

Domain:

http:Request

Range:

http:Response

This property relates a resource of type http:Response to a resource of type http:StatusCode.

Domain:

http:Response

Range:

http:StatusCode

The status code value (integer) corresponding to the standardized status code value.

Domain:

http:StatusCode

Range:

http://www.w3.org/2001/XMLSchema#int

The actual status code value sent by the server (Literal).

Domain:

http:Response

Range:

Literal

The following example shows an RDF/XML representation of an HTTP request and response pair.

A client sends two requests to a server at www.example.org port 80 via HTTP 1.1 GET. With each request, it sends request headers. The first request is for a resource in the document root (/), the second for a resource at /image. While handling the second request the server performs content negotiation respecting the request's Accept header and so sends a PNG image. This is indicated by the response's Vary header.

<?xml version="1.0" encoding="utf-8"?>
<rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
 xmlns:http="http://www.w3.org/2011/http#"
 xmlns:cnt="http://www.w3.org/2011/content#"
 xmlns:dct="http://purl.org/dc/terms/">

 <http:Connection rdf:ID="conn">
 <http:connectionAuthority>www.example.org:80</http:connectionAuthority>
 <http:requests rdf:parseType="Collection">
 <http:Request rdf:about="#req0"/>
 <http:Request rdf:about="#req1"/>
 </http:requests>
 </http:Connection>

 <http:Request rdf:about="#req0">
 <http:httpVersion>1.1</http:httpVersion>
 <http:methodName>GET</http:methodName>
 <http:mthd rdf:resource="http://www.w3.org/2011/http-methods#GET"/>
 <http:absolutePath>/</http:absolutePath>
 <http:headers rdf:parseType="Collection">
 <http:RequestHeader>
 <http:fieldName>Host</http:fieldName>
 <http:hdrName rdf:resource="http://www.w3.org/2011/http-headers#host"/>
 <http:fieldValue>www.example.org</http:fieldValue>
 </http:RequestHeader>
 <http:RequestHeader>
 <http:fieldName>User-Agent</http:fieldName>
 <http:hdrName rdf:resource="http://www.w3.org/2011/http-headers#user-agent"/>
 <http:fieldValue>My User Agent</http:fieldValue>
 </http:RequestHeader>
 <http:RequestHeader>
 <http:fieldName>Accept</http:fieldName>
 <http:hdrName rdf:resource="http://www.w3.org/2011/http-headers#accept"/>
 <http:fieldValue>text/html, image/png, image/gif;q=0.8</http:fieldValue>
 <http:headerElements rdf:parseType="Collection">
 <http:HeaderElement>
 <http:elementName>text/html</http:elementName>
 </http:HeaderElement>
 <http:HeaderElement>
 <http:elementName>image/png</http:elementName>
 </http:HeaderElement>
 <http:HeaderElement>
 <http:elementName>image/gif</http:elementName>
 <http:params rdf:parseType="Collection">
 <http:Parameter>
 <http:paramName>q</http:paramName>
 <http:paramValue>0.8</http:paramValue>
 </http:Parameter>
 </http:params>
 </http:HeaderElement>
 </http:headerElements>
 </http:RequestHeader>
 </http:headers>
 <http:resp rdf:resource="#resp0"/>
 </http:Request>

 <http:Request rdf:about="#req1">
 <http:httpVersion>1.1</http:httpVersion>
 <http:methodName>GET</http:methodName>
 <http:mthd rdf:resource="http://www.w3.org/2011/http-methods#GET"/>
 <http:absolutePath>/image</http:absolutePath>
 <http:headers rdf:parseType="Collection">
 <http:RequestHeader>
 <http:fieldName>Host</http:fieldName>
 <http:hdrName rdf:resource="http://www.w3.org/2011/http-headers#host"/>
 <http:fieldValue>www.example.org</http:fieldValue>
 </http:RequestHeader>
 <http:RequestHeader>
 <http:fieldName>User-Agent</http:fieldName>
 <http:hdrName rdf:resource="http://www.w3.org/2011/http-headers#user-agent"/>
 <http:fieldValue>My User Agent</http:fieldValue>
 </http:RequestHeader>
 <http:RequestHeader>
 <http:fieldName>Accept</http:fieldName>
 <http:hdrName rdf:resource="http://www.w3.org/2011/http-headers#accept"/>
 <http:fieldValue>image/png, image/gif;q=0.8</http:fieldValue>
 <http:headerElements rdf:parseType="Collection">
 <http:HeaderElement>
 <http:elementName>image/png</http:elementName>
 </http:HeaderElement>
 <http:HeaderElement>
 <http:elementName>image/gif</http:elementName>
 <http:params rdf:parseType="Collection">
 <http:Parameter>
 <http:paramName>q</http:paramName>
 <http:paramValue>0.8</http:paramValue>
 </http:Parameter>
 </http:params>
 </http:HeaderElement>
 </http:headerElements>
 </http:RequestHeader>
 </http:headers>
 <http:resp rdf:resource="#resp1"/>
 </http:Request>

 <http:Response rdf:ID="resp0">
 <http:httpVersion>1.1</http:httpVersion>
 <http:statusCodeValue>200</http:statusCodeValue>
 <http:sc rdf:resource="http://www.w3.org/2011/http-statusCodes#OK"/>
 <http:reasonPhrase>OK</http:reasonPhrase>
 <http:headers rdf:parseType="Collection">
 <http:GeneralHeader>
 <http:fieldName>Date</http:fieldName>
 <http:hdrName rdf:resource="http://www.w3.org/2011/http-headers#date"/>
 <http:fieldValue>.......</http:fieldValue>
 </http:GeneralHeader>
 <http:EntityHeader>
 <http:fieldName>Content-Type</http:fieldName>
 <http:hdrName rdf:resource="http://www.w3.org/2011/http-headers#content-type"/>
 <http:fieldValue>text/html; charset=utf-8</http:fieldValue>
 <http:headerElements rdf:parseType="Collection">
 <http:HeaderElement>
 <http:elementName>text/html</http:elementName>
 <http:params rdf:parseType="Collection">
 <http:Parameter>
 <http:paramName>charset</http:paramName>
 <http:paramValue>utf-8</http:paramValue>
 </http:Parameter>
 </http:params>
 </http:HeaderElement>
 </http:headerElements>
 </http:EntityHeader>
 </http:headers>
 <http:body>
 <cnt:ContentAsBase64 rdf:ID="cont0-bin">
 <cnt:bytes rdf:datatype="http://www.w3.org/2001/XMLSchema#base64Binary">ajrq9qguojbglj48z..........</cnt:bytes>
 <dct:isFormatOf rdf:resource="http://www.example.org/"/>
 </cnt:ContentAsBase64>
 </http:body>
 </http:Response>

 <http:Response rdf:ID="resp1">
 <http:httpVersion>1.1</http:httpVersion>
 <http:statusCodeValue>200</http:statusCodeValue>
 <http:sc rdf:resource="http://www.w3.org/2011/http-statusCodes#OK"/>
 <http:reasonPhrase>OK</http:reasonPhrase>
 <http:headers rdf:parseType="Collection">
 <http:MessageHeader>
 <http:fieldName>Date</http:fieldName>
 <http:hdrName rdf:resource="http://www.w3.org/2011/http-headers#date"/>
 <http:fieldValue>.......</http:fieldValue>
 </http:MessageHeader>
 <http:MessageHeader>
 <http:fieldName>Content-Type</http:fieldName>
 <http:hdrName rdf:resource="http://www.w3.org/2011/http-headers#content-type"/>
 <http:fieldValue>image/png</http:fieldValue>
 </http:MessageHeader>
 <http:MessageHeader>
 <http:fieldName>Vary</http:fieldName>
 <http:hdrName rdf:resource="http://www.w3.org/2011/http-headers#vary"/>
 <http:fieldValue>accept</http:fieldValue>
 <http:headerElements rdf:parseType="Collection">
 <http:HeaderElement>
 <http:elementName>accept</http:elementName>
 </http:HeaderElement>
 </http:headerElements>
 </http:MessageHeader>
 </http:headers>
 <http:body>
 <cnt:ContentAsBase64>
 <cnt:bytes rdf:datatype="http://www.w3.org/2001/XMLSchema#base64Binary">qouh3908t38hohfrf..........</cnt:bytes>
 <dct:isFormatOf rdf:resource="http://www.example.org/image"/>
 </cnt:ContentAsBase64>
 </http:body>
 </http:Response>

</rdf:RDF>

The following terms are defined by this specification:

[]

Representing Content in RDF - Johannes Koch, Carlos A Velasco, Philip Ackermann (editors). W3C Working Draft 27 April 2011.

[]

Evaluation and Report Language (EARL) Overview - W3C

[]

"HTTP Status Code Registry" - IANA.

[]

Web Ontology Language (OWL) Overview - W3C

[]

Permanent Message Header Field Names - IANA.

[]

Provisional Message Header Field Names - IANA.

[]

Protocol for Web Description Resources (POWDER): Description Resources - P. Archer, K. Smith, A. Perego (editors). W3C Proposed Recommendation 04 June 2009.

[]

Resource Description Framework (RDF) Overview - W3C

[]

RDF Primer - Frank Manola, Eric Miller (editors). W3C Recommendation, 10 February 2004.

[]

RDF Vocabulary Description Language 1.0: RDF Schema - Dan Brickley, R.V. Guha (editors). W3C Recommendation 10 February 2004

[]

Request for Comments (RFC): 2119. Key words for use in RFCs to Indicate Requirement Levels - IETF March 1997.

[]

Hypertext Transfer Protocol -- HTTP/1.1 - R. Fielding, J. Gettys, J. Mogul, H. Frystyk Nielsen, L. Masinter, P. Leach and T. Berners-Lee. IETF June 1999.

[]

HTTP Header Field Registrations - M. Nottingham, J. Mogul. IETF December 2005.

[]

PATCH Method for HTTP - L. Dusseault, Linden Lab, J. Snell. IETF March 2010.

[]

Web Content Accessibility Guidelines (WCAG) Overview - W3C.

[]

Extensible Markup Language (XML) 1.0 (Fifth Edition) - Tim Bray, Jean Paoli, C. M. Sperberg-McQueen, Eve Maler, François Yergeau (editors). W3C Recommendation 26 November 2008

The following is a list of substantial changes since the 29 October 2009 Working Draft:

• Added new classes GeneralHeader, ResponseHeader, RequestHeader and EntityHeader as subclasses of MessageHeader.
• Added HTTP PATCH method.
• Added statusCodeNumber to class StatusCode
• Changed domain of statusCodeValue to class Response.
• Fixed inconsistencies in RDF Schemas (HTTP and Status Codes).
• Examples adapted.
• Changed abs_Path to absolutePath.
• Removed conformance section.

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