Network Working Group J. Gregorio, Ed.
Internet-Draft BitWorking, Inc
Expires: March 22, 2005 R. Sayre, Ed.
Boswijck Memex Consulting
September 21, 2004
The Atom Publishing Protocol
draft-ietf-atompub-protocol-02.txt
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Copyright Notice
Copyright (C) The Internet Society (2004). All Rights Reserved.
Abstract
This memo presents a protocol for using XML (Extensible Markup
Language) and HTTP (HyperText Transport Protocol) to edit content.
The Atom Publishing Protocol is an application-level protocol for
publishing and editing Web resources belonging to periodically
updated websites. The protocol at its core is the HTTP transport of
Atom-formatted representations. The Atom format is documented in the
Atom Syndication Format (draft-ietf-atompub-format-02.txt).
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Editorial Note
To provide feedback on this Internet-Draft, join the
<http://www.imc.org/atom-syntax/index.html>.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 4
1.1 Notational Conventions . . . . . . . . . . . . . . . . . . 4
1.2 Terminology . . . . . . . . . . . . . . . . . . . . . . . 4
2. The Atom Publishing Protocol Model . . . . . . . . . . . . . 4
3. Functional Specification . . . . . . . . . . . . . . . . . . 5
3.1 PostURI . . . . . . . . . . . . . . . . . . . . . . . . . 5
3.1.1 Locating the PostURI . . . . . . . . . . . . . . . . . 5
3.1.2 Request . . . . . . . . . . . . . . . . . . . . . . . 5
3.1.3 Response . . . . . . . . . . . . . . . . . . . . . . . 5
3.2 EditURI . . . . . . . . . . . . . . . . . . . . . . . . . 7
3.2.1 Locating . . . . . . . . . . . . . . . . . . . . . . . 7
3.2.2 Request . . . . . . . . . . . . . . . . . . . . . . . 7
3.3 FeedURI . . . . . . . . . . . . . . . . . . . . . . . . . 9
3.3.1 Locating . . . . . . . . . . . . . . . . . . . . . . . 10
3.3.2 Request . . . . . . . . . . . . . . . . . . . . . . . 10
3.3.3 Response . . . . . . . . . . . . . . . . . . . . . . . 10
3.4 ResourcePostURI . . . . . . . . . . . . . . . . . . . . . 10
3.4.1 Locating . . . . . . . . . . . . . . . . . . . . . . . 10
3.4.2 Request . . . . . . . . . . . . . . . . . . . . . . . 11
3.4.3 Response . . . . . . . . . . . . . . . . . . . . . . . 11
3.5 Link Tag . . . . . . . . . . . . . . . . . . . . . . . . . 12
3.5.1 rel . . . . . . . . . . . . . . . . . . . . . . . . . 12
3.5.2 href . . . . . . . . . . . . . . . . . . . . . . . . . 12
3.5.3 title . . . . . . . . . . . . . . . . . . . . . . . . 13
3.5.4 type . . . . . . . . . . . . . . . . . . . . . . . . . 13
3.6 Atom Request and Response Body Constraints . . . . . . . . 13
3.6.1 id . . . . . . . . . . . . . . . . . . . . . . . . . . 13
3.6.2 link . . . . . . . . . . . . . . . . . . . . . . . . . 13
3.6.3 title . . . . . . . . . . . . . . . . . . . . . . . . 13
3.6.4 summary . . . . . . . . . . . . . . . . . . . . . . . 14
3.6.5 content . . . . . . . . . . . . . . . . . . . . . . . 14
3.6.6 issued . . . . . . . . . . . . . . . . . . . . . . . . 14
3.6.7 modified . . . . . . . . . . . . . . . . . . . . . . . 15
3.6.8 created . . . . . . . . . . . . . . . . . . . . . . . 15
3.6.9 author . . . . . . . . . . . . . . . . . . . . . . . . 15
3.6.10 contributor . . . . . . . . . . . . . . . . . . . . 15
3.6.11 generator . . . . . . . . . . . . . . . . . . . . . 15
3.7 Securing the Atom Protocol . . . . . . . . . . . . . . . . 16
3.7.1 [@@TBD@@ CGI Authentication] . . . . . . . . . . . . . 16
4. Security Considerations . . . . . . . . . . . . . . . . . . 16
5. IANA Considerations . . . . . . . . . . . . . . . . . . . . 17
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6. Appendix A - SOAP Enabling . . . . . . . . . . . . . . . . . 17
6.1 Servers . . . . . . . . . . . . . . . . . . . . . . . . . 17
6.2 Clients . . . . . . . . . . . . . . . . . . . . . . . . . 17
7. Appendix B - Examples . . . . . . . . . . . . . . . . . . . 17
7.1 Example for a weblog . . . . . . . . . . . . . . . . . . . 17
7.2 Example for a wiki . . . . . . . . . . . . . . . . . . . . 18
8. Revision History . . . . . . . . . . . . . . . . . . . . . . 18
9. Normative References . . . . . . . . . . . . . . . . . . . . 19
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . 20
Intellectual Property and Copyright Statements . . . . . . . 21
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1. Introduction
The Atom Publishing Protocol is an application-level protocol for
publishing and editing Web resources using HTTP [RFC2616] and XML.
1.1 Notational Conventions
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in [RFC2119].
1.2 Terminology
Atom Entry: An Atom Entry is a fragment of a full Atom feed. In this
case, the fragment is a single 'entry' element and all its child
elements. Each Atom Entry describes a single Web resource,
providing metadata and optionally a textual representation of that
resource.
PostURI: A URI that is used to create new resources. POSTing an Atom
Entry to this URI will create a new resource.
EditURI: A URI that is used to edit a resource. The editing is done
using the HTTP verbs GET, PUT and DELETE. The representation of
the resource is always that of an Atom Entry.
FeedURI: The URI which identifies an Atom Feed.
2. The Atom Publishing Protocol Model
The Atom Publishing Protocol is an application-level protocol for
publishing and editing Web resources. Using the common HTTP verbs
provides a pattern for working with all such Web resources:
o GET is used to retrieve a representation of a resource or perform
a read-only query.
o PUT is used to update a known resource.
o POST is used to create a new dynamically-named resource.
o DELETE is used to remove a resource.
There are four major classes of URI [RFC2396] in this specification:
PostURI, ResourcePostURI, FeedURI, and EditURI. This specification
defines the expected actions for each of the methods listed. A URI
MAY support methods not listed here. For example, an EditURI could
support a POST or OPTIONS method. However, what those methods do is
beyond the scope of this specification.
o EditURI: PUT, GET, DELETE
o PostURI: POST
o FeedURI: GET
o ResourcePostURI: POST
This document does not specify the form of the URIs that are used.
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The URI space of each server is controlled, as defined by HTTP, by
the server alone. What this document does specify are the formats of
the files that are exchanged and the actions that can be performed on
the URIs embedded in those files.
3. Functional Specification
3.1 PostURI
The PostURI is used to create entries. These can be either full
entries, such as a weblog post, or they can be comments, or even a
wiki page. The client POSTs a filled-in Atom Entry to this URI. If
the request is successful, one or more Web resources MAY be created.
For example, POSTing an Atom entry to a PostURI may create two new
Web resources, an HTML representation and an Atom representation.
3.1.1 Locating the PostURI
The PostURI can be discovered in a link element with an @rel of
'service.post'. The link element containing a PostURI used to create
a new entry MAY be discovered in three different places. The first
place it may be found is in a <link> element in the 'head' element of
an HTML document.
The second place a PostURI may be found an atom:link element that is
a child of the atom:feed element. The third place a PostURI may be
found is in the atom:link element of an atom:entry.
@@ TBD @@ - Discuss subordinate resources and what a PostURI means
based on where the URI was found.
<link rel="service.post"
type="application/atom+xml"
href="URI for Posting goes here"
title="The name of the site." />
3.1.2 Request
The request contains a filled-in Atom entry, subject to the
constraints in section Section 3.6.
3.1.3 Response
The possible status codes from a POST are 201, 303, 400, 404, 409,
410 and 500.
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3.1.3.1 Response code 201
The Response MUST include a Location: header with the URI of the
created resource. The URI returned must be the EditURI of the entry
just created. The body of the response SHOULD contain the newly
created entry. If the entry is present in the response body then it
MUST conform to the same constraints listed for responses to a GET on
an EditURI. User agents MUST NOT depend on the server returning a
response body. If the server does return a response body then the
user agents MUST NOT depend on the response body having a
content-type of 'application/atom+xml". Note that the server may
choose to omit the content in the response, particularly if it is
large.
A 201 response MAY contain an ETag response header field indicating
the current value of the entity tag for the requested variant just
created.
If the entry returned is subsequently changed the user agent can
update the entry by submitting it via PUT to the EditURI. If an ETag
was returned with the creation of the entry then the user agent
SHOULD include an If-Match: header in the request that contains that
ETag.
3.1.3.2 Response code 303
The body of this response does not contain the filled-in Entry, but
the filled-in Entry can be found under a different URI and can be
retrieved using a GET method on that resource. The URI SHOULD be
given by the Location field in the response.
3.1.3.3 Response code 400
Indicates that the server believes that the data sent constitutes an
invalid request. As an example, the data posted may not be
well-formed XML. The server SHOULD include an entity containing an
explanation of the error situation, and whether it is a temporary or
permanent condition.
3.1.3.4 Response code 409
The request contained a valid Atom Entry, but it conflicts with state
on the server. The response SHOULD contain enough for information
for the user to resolve the conflict.
[[@@TBD@@ more about response body format]]
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3.1.3.5 Response code 500
Indicates that the server detected an internal error on the server
processing this request (such as an unhandled exception). The server
SHOULD include an entity containing an explanation of the error
situation, and whether it is a temporary or permanent condition.
3.2 EditURI
An EditURI is used to edit a single entry. Each entry that is
editable MUST have a unique URI. This URI supports both GET and PUT
and they are used in tandem for an editing cycle. The client GETs
the representation which is formatted as an Atom entry. The client
may then update the entry and then PUT it back to the same URI. The
PUT will cause all the related resources to be updated, for example,
the HTML representation.
Note that the value of the content element in the Atom entry does not
have to exactly match the content element for the same entry when it
is represented in an Atom feed. For example, a server may allow the
client to post entries whose content is formatted as WikiML, yet the
server may clean up such markup and transform it into well-formed
XHTML before placing it in the publicly available Atom feed. Another
scenario is summaries--the EditURI is for editing the full content of
an entry, but the server may only present excerpts when it produces
an Atom feed.
A client will send a DELETE to the EditURI to delete an entry.
3.2.1 Locating
For editing a site Entry, the link tag is used. Note that a link tag
is used in both HTML and in the Atom format. A link tag of the
following format points to the EditURI for a site. In HTML, the link
tags for editing are always found in the head element, while in Atom
they may appear as children of the entry elements.
<link rel="service.edit"
type="application/atom+xml"
href="URI for Editing goes here"
title="Readable desc of the entry." />
Note: The critical characteristic of this link tag is the @rel of
'service.edit' and the @type of 'application/atom+xml'.
3.2.2 Request
A PUT request, and a GET response both contain a filled-in Atom
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entry, subject to the constraints in section Section 3.6.
The expected status codes from a GET are 200, 301, 307, and 500.
400, 404, and 410 are also possible.
The expected status codes from a PUT are 2xx, 301, 307, 500 and 501.
400, 404, 409, and 410 are also possible.
3.2.2.1 Successful Requests
Servers MUST indicate successful GET requests with a 200 response.
Servers MUST indicate successful PUT requests with a 2xx response.
Servers MAY include additional information in the PUT response.
Clients SHOULD NOT expect any additional information in a PUT
response.
3.2.2.2 Response code 301
The entry has moved permanently, the new URI is given in the Location
header. The client SHOULD retry the GET using the URI returned in
the Location header. When a PUT operation is attempted the user
agent should prompt the user before attempting the PUT on the URI
returned in the Location header.
3.2.2.3 Response code 307
The entry has moved temporarily, the new URI is given in the Location
header. The client SHOULD retry the GET using the URI returned in
the Location header. When a PUT operation is attempted the user
agent should prompt the user before attempting the PUT on the URI
returned in the Location header.
3.2.2.4 Response code 401
Indicates that the server believes that the data sent constitutes an
invalid request. As an example, the data posted may not be
well-formed XML. The server SHOULD include an entity containing an
explanation of the error situation, and whether it is a temporary or
permanent condition.
3.2.2.5 Response code 409
The request contained a valid Atom Entry, but it conflicts with the
state of the resource, or other state on the server.
For example, a server could signal that the client has erred in this
manner if it receives a request containing an atom:id element whose
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value differs from that of the resource found at the requested URI.
The response SHOULD contain enough for information for the user to
resolve the conflict.
[[@@TBD@@ more about response body format ]]
3.2.2.6 Response code 410
Indicates that the requested resource is gone permanently. The
client SHOULD NOT repeat the request.
3.2.2.7 Response code 500
Indicates that the server detected an internal error on the server
processing this request (such as an unhandled exception). The server
SHOULD include an entity containing an explanation of the error
situation, and whether it is a temporary or permanent condition.
3.3 FeedURI
The FeedURI is used to retrieve a representation in Atom format.
Note that this feed is different from a typical Atom feed in that it
contains "link" elements for navigating and manipulating the content
of the site. For example there should be a "link" element with
rel="next" whose URI points to the next block of entries on the site.
Similarly, the feed element can contain a "link" element with
rel="service.post", the URI of which is a PostURI. Individual
entries should contain "link" elements with rel="service.edit" whose
URIs are EditURIs.
This document only uses some of the methods available for each type
of URI. For example, the only method described by this document for
the FeedURI is GET. Any other method may be supported by the URI
types described, but defining their behavior is beyond the scope of
this document. In this light you may notice that the PostURI only
supports the POST method. It is possible, and allowable, that for
some implementations the PostURI and the FeedURI are the same URI.
@@ Editor's Note: @@ Note that the "service.feed" takes the place of
the Introspection File and the Search facet in previous versions of
the specification. That is, facet discovery, which was previously
done by inspecting the Introspection file is now done by looking for
"link" tags with an attribute "rel" set to "service.[something]" in
the "service.feed" file. At the same time the same representation
replaces the search facet by having "link" tags that point to other
feeds using well-known 'rel' attribute values such as 'next' and
'prev', or the search can branch in multiple directions by specifying
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multiple link tags with rel="service.feed" and having differing title
attributes that announce the kind of search results in that feed.
3.3.1 Locating
A link tag of the following format points to the FeedURI.
<link rel="service.feed"
type="application/atom+xml"
href="URI goes here"
title="The name of the site." />
3.3.2 Request
The request is a simple GET. No other verbs are currently specified
for this URI.
3.3.3 Response
The expected status codes from a GET are 200, 301, 307, and 500.
401, 404, and 410 are also possible.
3.3.3.1 Response code 301
The Feed has moved permanently, the new URI is given in the Location
header. The client SHOULD do a GET on the URI returned in the
Location header.
3.3.3.2 Response code 307
The Feed has moved temporarily, the new URI is given in the Location
header. The client SHOULD do a GET on the URI returned in the
Location header.
3.4 ResourcePostURI
The ResourcePostURI is used to create new non-entry resources. The
client POSTs a resource of the desired MIME type directly to this
URI.
3.4.1 Locating
For creating a new non-entry resource, the link tag is used. Note
that a link tag is used in both HTML and in the Atom format. A link
tag of the following format points to the ResourcePostURI for a site.
In HTML the link tags are always found in the head element, while in
Atom they may appear as children of the Feed and entry elements.
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<link rel="resource.post" href="URI for Resource Posting goes here"
title="The name of the site.">
3.4.2 Request
The request contains a resource, sent through a standard HTTP POST,
e.g.:
POST /_do/exampleblog/post_resource HTTP/1.1
Host: www.example.com
Content-Type: image/jpeg
Content-Length: nnn
...raw bytes of image go here...
3.4.3 Response
The expected status codes from a POST are 201, 303, 400, 415, and
500. 401, 404, 409, and 410 are also possible.
3.4.3.1 Response code 201
The response MUST include a Location: header with the URI of the
created resource, i.e. the URI used to retrieve the resource
representation in a subsequent HTTP GET. The server SHOULD omit the
content of the resource in the response, since it would be redundant
to return it to the client.
3.4.3.2 Response code 303
Similar to 201 but no caching is allowed. The response MUST include
a Location: header.
3.4.3.3 Response code 400
Indicates that the server believes that the data sent constitutes an
invalid request. The server SHOULD include an entity containing an
explanation of the error situation, and whether it is a temporary or
permanent condition.
3.4.3.4 Response code 415
The MIME type of the request entity is not supported by the server
for this resource.
The response SHOULD contain enough for information for the user to
resolve the conflict.
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[[@@TBD@@ more about response body format ]]
3.4.3.5 Response code 500
Indicates that the server detected an internal error on the server
processing this request (such as an unhandled exception). A short
description of the error will appear on the status line itself. A
longer description will appear in the body.
3.5 Link Tag
The link tag is used in both HTML and Atom formats. There are slight
differences between the two usages. Here are the commonalities,
differences, and a list of well-known values for the rel attribute.
<http://www.w3.org/TR/html4/struct/links.html#edef-LINK> appears in
the 'head' of the document. The 'head' section only allows a linear
list of 'link' tags. The Atom format allows 'link' tags as children
of both the 'feed' element and of the 'entry' element. Note that
this gives the information present in the link tag more context. For
example ... @@ TBD @@
3.5.1 rel
This attribute describes the relationship from the current document,
be it HTML or Atom, to the anchor specified by the href attribute.
The value of this attribute is a space-separated list of link types.
Note that these values are case insensitive. When used in concert
with type="application/atom+xml", the relations may be interpreted as
follows.
alternate: The URI in the href attribute points to an alternate
representation of the containing resource.
start: The Atom feed at the URI supplied in the href attribute
contains the first feed in a linear sequence of entries.
next: The Atom feed at the URI supplied in the href attribute
contains the next N entries in a linear sequence of entries.
prev: The Atom feed at the URI supplied in the href attribute
contains the previous N entries in a linear sequence of entries.
service.edit: The URI given in the href attribute is used to edit a
representation of the referred resource.
service.post: The URI in the href attribute is used to create new
resources.
service.feed: The URI given in the href attribute is a starting point
for navigating content and services.
3.5.2 href
URI of the resource being described by this link element.
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3.5.3 title
Offers advisory information about the link. Rendered to the user to
help them choose among a set of links with the same rel and type
attributes.
3.5.4 type
The content type of the resource available at the URI given in the
href attribute of the link element. Most of the link types in this
specification are on type 'application/atom+xml'.
3.6 Atom Request and Response Body Constraints
The Atom format is used as the representation of all the resources in
this specification. As it is used in differing contexts, there are
different constraints of which elements may be present, and how their
values should be interpreted.
3.6.1 id
PostURI MUST NOT be present.
FeedURI MUST be present.
EditURI
GET MUST be present.
PUT MUST be present.
3.6.2 link
PostURI MAY be present. Servers MAY use the information to determine
the URI of the created resource. Relative URLs are to be
interpreted relative to xml:base.
FeedURI MUST be present.
EditURI
GET MUST be present.
PUT MUST be present.
3.6.3 title
PostURI MUST be present. The element may be empty, to explicitly
indicate "no title". Servers SHOULD NOT try to generate a title
if one is not provided. The type attribute MAY be present, and if
not it defaults to "text/plain". If present, it MUST represent a
MIME type that the server supports. The mode attribute MAY be
present. If not present, it defaults to "xml". If present, it
MUST be "xml", "base64", or "escaped".
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FeedURI MUST be present.
EditURI
GET MUST be present.
PUT MUST be present. The element may be empty, to explicitly
indicate "no title". Servers SHOULD NOT try to generate a
title if one is not provided.
3.6.4 summary
PostURI MAY be present. If not present, the server is welcome to
produce its own summary. If present but empty, the server SHOULD
NOT generate a summary of its own. The type attribute MAY be
present. If not, it defaults to "text/plain". If present, it
must represent a MIME type that the server supports. The mode
attribute MAY be present and defaults to "xml". If present, it
must be "xml","base64", or "escaped".
FeedURI MAY be present.
EditURI
GET MAY be present.
PUT MAY be present. The element may be empty, to explicitly
indicate "no summary". Servers SHOULD NOT try to generate a
title if one is not provided.
3.6.5 content
PostURI MAY be present but may be empty, to explicitly indicate "no
content". The type attribute MAY be present, but defaults to
"text/plain" if not present. It must represent a MIME type that
the server supports. The MODE attribute may be present and
defaults to "xml" if not present. It must be "xml","base64", or
"escaped".
FeedURI MAY be present.
EditURI
GET MAY be present.
PUT MAY be present. The element may be empty, to explicitly
indicate "no content".
3.6.6 issued
PostURI MUST be present, but may be empty, in which case it signifies
"now" in the time zone of the server.
FeedURI MUST be present.
EditURI
GET MUST be present.
PUT MUST be present. Server policy determines if an updated time
is accepted.
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3.6.7 modified
PostURI MUST NOT be present.
FeedURI MAY be present.
EditURI
GET MAY be present.
PUT MAY be present. The element may be empty, to explicitly
indicate that 'now' on the server time is to be used.
3.6.8 created
PostURI MAY be present.
FeedURI MAY be present.
EditURI
GET MAY be present.
PUT MAY be present. The server may or may not accept an updated
value. If the server does not allow updating the issued time
then any PUT request with a different issued value MUST be
rejected.
3.6.9 author
PostURI MAY be present. If not present, the server determines the
author. If present, and conflicting with valid values as
determined by the server, then the server may change the value of
author.
FeedURI MAY be present.
EditURI
GET MAY be present.
PUT MAY be present.
3.6.10 contributor
PostURI MAY be present.
FeedURI MAY be present.
EditURI
GET MAY be present.
PUT MAY be present.
3.6.11 generator
PostURI MUST be present and contain a URI. The value of the element
indicates the code base used to create this request. MUST also
have an attribute 'version' with a version number.
FeedURI MUST NOT be present.
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EditURI
GET MUST NOT be present.
PUT MUST NOT be present.
3.7 Securing the Atom Protocol
All instances of publishing Atom entries SHOULD be protected by
authentication to prevent posting or editing by unknown sources.
Atom servers and clients MUST support one of the following
authentication mechanisms, and SHOULD support both.
o HTTP Digest Authentication [RFC2617]
o [@@TBD@@ CGI Authentication ref]
Atom servers and clients MAY support encryption of the Atom session
using TLS [RFC2246].
There are cases where an authentication mechanism may not be
required, such as a publicly editable Wiki, or when using the PostURI
to post comments to a site that does not require authentication to
create comments.
3.7.1 [@@TBD@@ CGI Authentication]
This authentication method is included as part of the protocol to
allow Atom servers and clients that cannot use HTTP Digest
Authentication but where the user can both insert its own HTTP
headers and create a CGI program to authenticate entries to the
server. This scenario is common in environments where the user
cannot control what services the server employs, but the user can
write their own HTTP services.
4. Security Considerations
Because Atom is a publishing protocol, it is important that only
authorized users can create and edit entries.
The security of Atom is based on HTTP Digest Authentication and/or
[@@TBD@@ CGI Authentication]. Any weaknesses in either of these
authentication schemes will obviously affect the security of the Atom
Publishing Protocol.
Both HTTP Digest Authentication and [@@TBD@@ CGI Authentication] are
susceptible to dictionary-based attacks on the shared secret. If the
shared secret is a password (instead of a random string with
sufficient entropy), an attacker can determine the secret by
exhaustively comparing the authenticating string with hashed results
of the public string and dictionary entries.
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See RFC 2617 for more detailed description of the security properties
of HTTP Digest Authentication.
@@TBD@@ Talk here about using HTTP basic and digest authentication.
@@TBD@@ Talk here about denial of service attacks using large XML
files, or the billion laughs DTD attack.
5. IANA Considerations
This document has no actions for IANA.
6. Appendix A - SOAP Enabling
All servers SHOULD support the following alternate interface
mechanisms to enable a wider variety of clients to interact with Atom
Publishing Protocol servers. The following requirements are in
addition to the ones listed in the Functional Specification Section.
If a server supports SOAP Enabling then it MUST support all of the
following.
6.1 Servers
1. All servers MUST support the limited use of the SOAPAction HTTP
Header as described below in the Client section.
2. All servers MUST be able to process well formed XML. Servers
need not be able to handle processing instructions or DTDs.
3. Servers MUST accept content in a SOAP Envelope, and if they
receive a request that is wrapped in a SOAP Envelope then they
MUST wrap their responses in SOAP envelopes or produce a SOAP
Fault.
6.2 Clients
1. Clients SHOULD use the appropriate HTTP Method when possible.
When not possible, they should use POST and include a SOAPAction
HTTP header which is constrained as follows:
2. SOAPAction: "http://schemas.xmlsoap.org/wsdl/http/[METHOD]"
3. Where [METHOD] is replaced by the desired HTTP Method.
4. Clients MAY wrap their XML payload in a SOAP Envelope. If so,
they must also wrap it in an element which exactly matches the
HTTP Method.
7. Appendix B - Examples
7.1 Example for a weblog
Fill this in with an example for how all the above is used for a
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weblog. Start with main HTML page, link tag of type service.feed to
the 'introspection' file. 1. Creating a new entry 2. Finding an
old entry 3. editing an old entry 4. commenting on a entry (via
HTML and Atom)
7.2 Example for a wiki
Fill this in like above but for a wiki.
8. Revision History
draft-ietf-atompub-protocol-02 - Incorporates Pace409Response,
PacePostLocationMust, and PaceSimpleResourcePosting.
draft-ietf-atompub-protocol-01 - Added in sections on Responses for
the EditURI. Allow 2xx for response to EditURI PUTs. Elided all
mentions of WSSE. Started adding in some normative references.
Added the section "Securing the Atom Protocol". Clarified that it is
possible that the PostURI and FeedURI could be the same URI. Cleaned
up descriptions for Response codes 400 and 500.
Rev draft-ietf-atompub-protocol-00 - 5Jul2004 - Renamed the file and
re-titled the document to conform to IETF submission guidelines.
Changed MIME type to match the one selected for the Atom format.
Numerous typographical fixes. We used to have two 'Introduction'
sections. One of them was moved into the Abstract the other absorbed
the Scope section. IPR and copyright notifications were added.
Rev 09 - 10Dec2003 - Added the section on SOAP enabled clients and
servers.
Rev 08 - 01Dec2003 - Refactored the specification, merging the
Introspection file into the feed format. Also dropped the
distinction between the type of URI used to create new entries and
the kind used to create comments. Dropped user preferences.
Rev 07 - 06Aug2003 - Removed the use of the RSD file for
auto-discovery. Changed copyright until a final standards body is
chosen. Changed query parameters for the search facet to all begin
with atom- to avoid name collisions. Updated all the Entries to
follow the 0.2 version. Changed the format of the search results and
template file to a pure element based syntax.
Rev 06 - 24Jul2003 - Moved to PUT for updating Entries. Changed all
the mime-types to application/x.atom+xml. Added template editing.
Changed 'edit-entry' to 'create-entry' in the Introspection file to
more accurately reflect it's purpose.
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Rev 05 - 17Jul2003 - Renamed everything Echo into Atom. Added
version numbers in the Revision history. Changed all the mime-types
to application/atom+xml.
Rev 04 - 15Jul2003 - Updated the RSD version used from 0.7 to 1.0.
Change the method of deleting an Entry from POSTing <delete/> to
using the HTTP DELETE verb. Also changed the query interface to GET
instead of POST. Moved Introspection Discovery to be up under
Introspection. Introduced the term 'facet' for the services listed
in the Introspection file.
Rev 03 - 10Jul2003 - Added a link to the Wiki near the front of the
document. Added a section on finding an Entry. Retrieving an Entry
now broken out into it's own section. Changed the HTTP status code
for a successful editing of an Entry to 205.
Rev 02 - 7Jul2003 - Entries are no longer returned from POSTs,
instead they are retrieved via GET. Cleaned up figure titles, as
they are rendered poorly in HTML. All content-types have been
changed to application/atom+xml.
Rev 01 - 5Jul2003 - Renamed from EchoAPI.html to follow the more
commonly used format: draft-gregorio-NN.html. Renamed all references
to URL to URI. Broke out introspection into it's own section. Added
the Revision History section. Added more to the warning that the
example URIs are not normative.
9 Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC2246] Dierks, T. and C. Allen, "The TLS Protocol Version 1.0",
RFC 2246, January 1999.
[RFC2396] Berners-Lee, T., Fielding, R. and L. Masinter, "Uniform
Resource Identifiers (URI): Generic Syntax", RFC 2396,
August 1998.
[RFC2616] Fielding, R., Gettys, J., Mogul, J., Frystyk, H.,
Masinter, L., Leach, P. and T. Berners-Lee, "Hypertext
Transfer Protocol -- HTTP/1.1", RFC 2616, June 1999.
[RFC2617] Franks, J., Hallam-Baker, P., Hostetler, J., Lawrence, S.,
Leach, P., Luotonen, A. and L. Stewart, "HTTP
Authentication: Basic and Digest Access Authentication",
RFC 2617, June 1999.
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Authors' Addresses
Joe Gregorio (editor)
BitWorking, Inc
1002 Heathwood Dairy Rd.
Apex, NC 27502
US
Phone: +1 919 272 3764
EMail: joe@bitworking.com
URI: http://bitworking.com/
Robert Sayre (editor)
Boswijck Memex Consulting
148 N 9th St. 4R
Brooklyn, NY 11211
US
EMail: rfsayre@boswijck.com
URI: http://boswijck.com
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