Network Working Group J. Gregorio, Ed.
Internet-Draft IBM
Intended status: Standards Track B. de hOra, Ed.
Expires: September 5, 2007 Propylon Ltd.
March 4, 2007
The Atom Publishing Protocol
draft-ietf-atompub-protocol-14.txt
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Abstract
The Atom Publishing Protocol (APP) is an application-level protocol
for publishing and editing Web resources. The protocol is based on
HTTP transfer of Atom-formatted representations. The Atom format is
documented in the Atom Syndication Format [RFC4287].
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Editorial Note
To provide feedback on this Internet-Draft, join the atom-protocol
mailing list (http://www.imc.org/atom-protocol/index.html) [1].
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 5
2. Notational Conventions . . . . . . . . . . . . . . . . . . . . 6
2.1. XML-related Conventions . . . . . . . . . . . . . . . . . 6
2.1.1. Referring to Information Items . . . . . . . . . . . . 6
2.1.2. RELAX NG Schema . . . . . . . . . . . . . . . . . . . 6
2.1.3. Use of xml:base and xml:lang . . . . . . . . . . . . . 6
3. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 7
4. Protocol Model . . . . . . . . . . . . . . . . . . . . . . . . 8
4.1. Client Implementation Considerations . . . . . . . . . . . 9
5. Protocol Operations . . . . . . . . . . . . . . . . . . . . . 11
5.1. Retrieving a Service Document . . . . . . . . . . . . . . 11
5.2. Listing Collection Members . . . . . . . . . . . . . . . . 11
5.3. Creating a Resource . . . . . . . . . . . . . . . . . . . 12
5.4. Editing a Resource . . . . . . . . . . . . . . . . . . . . 12
5.4.1. Retrieving a Resource . . . . . . . . . . . . . . . . 12
5.4.2. Updating a Resource . . . . . . . . . . . . . . . . . 13
5.4.3. Deleting a Resource . . . . . . . . . . . . . . . . . 13
5.5. Use of HTTP Response codes . . . . . . . . . . . . . . . . 13
6. Atom Publishing Protocol Documents . . . . . . . . . . . . . . 14
6.1. Document Types . . . . . . . . . . . . . . . . . . . . . . 14
6.2. Document Extensibility . . . . . . . . . . . . . . . . . . 14
7. Category Documents . . . . . . . . . . . . . . . . . . . . . . 16
7.1. Example . . . . . . . . . . . . . . . . . . . . . . . . . 16
7.2. Element Definitions . . . . . . . . . . . . . . . . . . . 16
7.2.1. The "app:categories" element . . . . . . . . . . . . . 16
8. Service Documents . . . . . . . . . . . . . . . . . . . . . . 18
8.1. Workspaces . . . . . . . . . . . . . . . . . . . . . . . . 18
8.2. Example . . . . . . . . . . . . . . . . . . . . . . . . . 19
8.3. Element Definitions . . . . . . . . . . . . . . . . . . . 20
8.3.1. The "app:service" Element . . . . . . . . . . . . . . 20
8.3.2. The "app:workspace" Element . . . . . . . . . . . . . 20
8.3.3. The "app:collection" Element . . . . . . . . . . . . . 21
8.3.4. The "app:accept" Element . . . . . . . . . . . . . . . 21
8.3.5. The "app:categories" Element . . . . . . . . . . . . . 22
9. Creating and Editing Resources . . . . . . . . . . . . . . . . 24
9.1. Member URIs . . . . . . . . . . . . . . . . . . . . . . . 24
9.2. Creating resources with POST . . . . . . . . . . . . . . . 24
9.2.1. Example . . . . . . . . . . . . . . . . . . . . . . . 25
9.3. Updating Resources with PUT . . . . . . . . . . . . . . . 26
9.4. Deleting Resources with DELETE . . . . . . . . . . . . . . 26
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9.5. Caching and entity tags . . . . . . . . . . . . . . . . . 26
9.5.1. Example . . . . . . . . . . . . . . . . . . . . . . . 26
9.6. Media Resources and Media Link Entries . . . . . . . . . . 28
9.6.1. Examples . . . . . . . . . . . . . . . . . . . . . . . 29
9.7. The Slug: Header . . . . . . . . . . . . . . . . . . . . . 35
9.7.1. Slug: Header syntax . . . . . . . . . . . . . . . . . 36
9.7.2. Example . . . . . . . . . . . . . . . . . . . . . . . 36
10. Listing Collections . . . . . . . . . . . . . . . . . . . . . 37
10.1. Collection partial lists . . . . . . . . . . . . . . . . . 37
10.2. The "app:edited" Element . . . . . . . . . . . . . . . . . 38
11. Atom Format Link Relation Extensions . . . . . . . . . . . . . 40
11.1. The "edit" Link Relation . . . . . . . . . . . . . . . . . 40
11.2. The "edit-media" Link Relation . . . . . . . . . . . . . . 40
12. The Atom Format Type Parameter . . . . . . . . . . . . . . . . 41
12.1. The 'type' parameter . . . . . . . . . . . . . . . . . . . 41
12.1.1. Conformance . . . . . . . . . . . . . . . . . . . . . 41
13. Atom Publishing Controls . . . . . . . . . . . . . . . . . . . 42
13.1. The "app:control" Element . . . . . . . . . . . . . . . . 42
13.1.1. The "app:draft" Element . . . . . . . . . . . . . . . 42
14. Securing the Atom Publishing Protocol . . . . . . . . . . . . 43
15. Security Considerations . . . . . . . . . . . . . . . . . . . 44
15.1. Denial of Service . . . . . . . . . . . . . . . . . . . . 44
15.2. Replay Attacks . . . . . . . . . . . . . . . . . . . . . . 44
15.3. Spoofing Attacks . . . . . . . . . . . . . . . . . . . . . 44
15.4. Linked Resources . . . . . . . . . . . . . . . . . . . . . 44
15.5. Digital Signatures and Encryption . . . . . . . . . . . . 44
15.6. URIs and IRIs . . . . . . . . . . . . . . . . . . . . . . 44
16. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 45
16.1. Content-type registration for
'application/atomserv+xml' . . . . . . . . . . . . . . . . 45
16.2. Content-type registration for 'application/atomcat+xml' . 46
16.3. Header field registration for 'SLUG' . . . . . . . . . . . 47
16.4. The Link Relation registration "edit" . . . . . . . . . . 48
16.5. The Link Relation registration "edit-media" . . . . . . . 48
16.6. The Atom Format Media Type Parameter . . . . . . . . . . . 48
17. References . . . . . . . . . . . . . . . . . . . . . . . . . . 49
17.1. Normative References . . . . . . . . . . . . . . . . . . . 49
17.2. Informative References . . . . . . . . . . . . . . . . . . 50
Appendix A. Contributors . . . . . . . . . . . . . . . . . . . . 52
Appendix B. RELAX NG Compact Schema . . . . . . . . . . . . . . . 53
Appendix C. Revision History . . . . . . . . . . . . . . . . . . 59
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 63
Intellectual Property and Copyright Statements . . . . . . . . . . 64
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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 1.0
[W3C.REC-xml]. The protocol supports the creation of Web resources
and provides facilities for:
o Collections: Sets of resources, which can be retrieved in whole or
in part.
o Services: Discovery and description of Collections.
o Editing: Creating, updating and deleting resources.
The Atom Publishing Protocol is different from many contemporary
protocols in that the server is given wide latitude in processing
requests from clients. See Section 4 for more details.
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2. 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].
2.1. XML-related Conventions
2.1.1. Referring to Information Items
Atom Protocol Document formats are specified in terms of the XML
Information Set [W3C.REC-xml-infoset], serialized as XML 1.0
[W3C.REC-xml].
The Infoset terms "Element Information Item" and "Attribute
Information Item" are shortened to "element" and "attribute"
respectively. Therefore, when this specification uses the term
"element", it is referring to an Element Information Item, and when
it uses the term "attribute", it is referring to an Attribute
Information Item.
2.1.2. RELAX NG Schema
Some sections of this specification are illustrated with fragments of
a non-normative RELAX NG Compact schema [RNC]. However, the text of
this specification provides the definition of conformance. Complete
schemas appear in Appendix B.
2.1.3. Use of xml:base and xml:lang
XML elements defined by this specification MAY have an xml:base
attribute [W3C.REC-xmlbase-20010627]. When xml:base is used, it
serves the function described in Section 5.1.1 of URI Generic Syntax
[RFC3986], by establishing the base URI (or IRI) for resolving
relative references found within the scope of the xml:base attribute.
Any element defined by this specification MAY have an xml:lang
attribute, whose content indicates the natural language for the
element and its descendents. Requirements regarding the content and
interpretation of xml:lang are specified in Section 2.12 of XML 1.0
[W3C.REC-xml].
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3. Terminology
For convenience, this protocol can be referred to as the "Atom
Protocol" or "APP".
URI/IRI - A Uniform Resource Identifier and Internationalized
Resource Identifier. These terms and the distinction between them
are defined in [RFC3986] and [RFC3987]. Before an IRI found in a
document is used by HTTP, the IRI is first converted to a URI (see
Section 4).
In this specification the phrase "the URI of a document" is shorthand
for "a URI which, when dereferenced, is expected to produce that
document as a representation".
Resource - A network-accessible data object or service identified by
an IRI, as defined in [RFC2616]. See [W3C.REC-webarch-20041215] for
further discussion on resources.
Representation - An entity included with a request or response as
defined in [RFC2616].
Collection - A resource that contains a set of Member Entries. See
Section 9.
Member - A resource whose IRI is listed in a Collection by a link
element with a relation of "edit" or "edit-media". See Section 9.1.
The protocol defines two kinds of Members - Entry and Media
resources.
Entry Resource - Member Resources of a Collection that are
represented using the "application/atom+xml" media type.
Media Resource -Member Resources of a Collection that are represented
with a media type other than "application/atom+xml".
Media Link Entry - an Entry Resource that contains metadata about a
Media Resource.
Workspace - A named group of Collections. See Section 8.1.
Service Document - A document that describes the location and
capabilities of one or more Collections. See Section 8.
Category Document - A document that describes the categories allowed
in a Collection. See Section 7.
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4. Protocol Model
The Atom Publishing Protocol uses HTTP methods to author Member
Resources as follows:
o GET is used to retrieve a representation of a known resource.
o POST is used to create a new, dynamically-named, resource. When
the client submits non-Atom-Entry representations to a Collection
for creation, two resources are always created - a Media Entry for
the requested resource, and a Media Link Entry for metadata (in
Atom Entry format) about the resource.
o PUT is used to update a known resource.
o DELETE is used to remove a known resource.
The Atom Protocol does not specify the form of the URIs that are
used. HTTP ([RFC2616]) specifies that the URI space of each server
is controlled by that server, and this protocol imposes no further
constraints on that control. What is specified here are the formats
of the representations that are exchanged and the actions that can be
performed on the IRIs embedded in those representations.
The Atom Protocol only covers the creation, update and deletion of
Entry and Media resources. Other resources could be created,
updated, and deleted as the result of manipulating a Collection, but
the number of those resources, their media-types, and effects of Atom
Protocol operations on them are outside the scope of this
specification.
Since all aspects of client-server interaction are defined in terms
of HTTP, [RFC2616] should be consulted for any areas not covered in
this specification.
Along with operations on Member Resources, the Atom Protocol defines
Collection Resources for managing and organizing Member Resources.
The representation of Collections are Atom Feed documents, and
contain the IRIs of, and metadata about the Collection's Member
Resources. The Atom Protocol does not make a structural distinction
between Feeds used for Collections and other Atom Feeds. The only
mechanism that this specification supplies for indicating a
Collection Feed is its appearance in a Service Document.
Atom Protocol documents allow the use of IRIs [RFC3987], as well as
URIs [RFC3986]. Before an IRI found in a document is used by HTTP,
the IRI is first converted to a URI according the procedure defined
in Section 3.1 of [RFC3987]. In accordance with that specification,
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this conversion SHOULD be applied as late as possible. Conversion
does not imply resource creation - the IRI and the URI into which it
is converted identify the same resource.
There are two kinds of Member Resources - Entry Resources and Media
Resources. Entry Resources are represented as Atom Entries
[RFC4287]. Media Resources can have representations in any media
type. A Media Link Entry is an Entry Resource that contains metadata
about a Media Resource. This diagram shows the classification of the
resources:
Member Resource
-> Entry Resource
-> Media Link Entry
-> Media Resource
A Collection Feed's Atom Entries contain the Entry and Media Resource
IRIs of the Collection. A Collection Feed can contain any number of
Entries for either kind, or an ordered subset of the Entries (see
Section 10.1). In the diagram of a Collection below, there are two
Entries. The first contains the IRI of an Entry Resource. The
second contains the IRIs of both a Media Resource and a Media Link
Entry Resource, which contains the metadata for that Media Resource:
Collection
Entry
Member Entry IRI -> Entry Resource
Entry
Member Entry IRI -> Media Link Entry
Media IRI -> Media Resource
Service Documents represent server-defined groups of Collections, and
are used to initialize the process of creating and editing resources.
4.1. Client Implementation Considerations
The Atom Protocol imposes few restrictions on the actions of servers.
Unless a constraint is specified here, servers can be expected to
vary in behavior, in particular around the manipulation of Atom
Entries sent by clients. For example, although this specification
only defines the expected behavior of Collections with respect to GET
and POST, this does not imply that PUT, DELETE, PROPPATCH and others
are forbidden on Collection resources - only that this specification
does not define what the server's response would be to those methods.
Similarly while some HTTP status codes are mentioned explicitly,
clients ought to be prepared to handle any status code from a server.
Servers can choose to accept, reject, delay, moderate, censor,
reformat, translate, relocate or recategorize the content submitted
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to them. Only some of these choices are immediately relayed back to
the client in responses to client requests; other choices may only
become apparent later, in the feed or published entries. The same
series of requests to two different publishing sites can result in a
different series of HTTP responses, different resulting feeds or
different entry contents.
As a result, client software has to be written flexibly to accept
what the server decides are the results of its submissions. Any
server response or server content modification not explicitly
forbidden by this specification or HTTP ([RFC2616]) is therefore
allowed.
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5. Protocol Operations
5.1. Retrieving a Service Document
Client Server
| |
| 1.) GET to Service Document |
|------------------------------------------>|
| |
| 2.) Service Document |
|<------------------------------------------|
| |
1. The client sends a GET request using the URI of the Service
Document.
2. The server responds with the document enumerating the IRIs of a
group of Collections and the capabilities of those Collections
supported by the server. The content of this document can vary
based on aspects of the client request, including, but not
limited to, authentication credentials.
5.2. Listing Collection Members
To list the members of a Collection, the client sends a GET request
to the URI of a Collection. An Atom Feed Document is returned whose
Entries contain the IRIs of Member Resources. The returned Feed may
describe all, or only a partial list of the Members in a Collection
(see Section 10).
Client Server
| |
| 1.) GET to Collection URI |
|------------------------------->|
| |
| 2.) Atom Feed Doc |
|<-------------------------------|
| |
1. The client sends a GET request to the URI of the Collection.
2. The server responds with an Atom Feed Document containing the
IRIs of the Collection members.
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5.3. Creating a Resource
Client Server
| |
| 1.) POST to URI of Collection |
|------------------------------------------>|
| |
| 2.) 201 Created |
| Location: Member Entry URI |
|<------------------------------------------|
| |
1. The client POSTs a representation of the Member to the URI of the
Collection.
2. If the Member Resource was created successfully, the server
responds with a status code of 201 and a Location: header that
contains the IRI of the newly created Entry Resource. Media
Resources could have also been created and their IRIs can be
found through the Entry Resource. See Section 9.6 for more
details.
5.4. Editing a Resource
Once a resource has been created and its Member URI is known, that
URI can be used to retrieve, update, and delete the resource.
Section 11 describes extensions to the Atom Syndication Format used
in the Atom Protocol for editing purposes.
5.4.1. Retrieving a Resource
Client Server
| |
| 1.) GET to Member URI |
|------------------------------------------>|
| |
| 2.) Member Representation |
|<------------------------------------------|
| |
1. The client sends a GET request to the URI of a Member Resource to
retrieve its representation.
2. The server responds with the representation of the resource.
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5.4.2. Updating a Resource
Client Server
| |
| 1.) PUT to Member URI |
|------------------------------------------>|
| |
| 2.) 200 OK |
|<------------------------------------------|
1. The client PUTs an updated representation to the URI of a Member
Resource.
2. If the update is successful the server responds with a status
code of 200.
5.4.3. Deleting a Resource
Client Server
| |
| 1.) DELETE to Member URI |
|------------------------------------------>|
| |
| 2.) 200 OK |
|<------------------------------------------|
| |
1. The client sends a DELETE request to the URI of a Member
Resource.
2. If the deletion is successful the server responds with a status
code of 200.
A different approach is taken for deleting Media Resources; see
Section 9.6 for details.
5.5. Use of HTTP Response codes
The Atom Protocol uses the response status codes defined in HTTP to
indicate the success or failure of an operation. Consult the HTTP
specification [RFC2616] for detailed definitions of each status code.
Implementers are asked to note that according to the HTTP
specification, HTTP 4xx and 5xx response entities SHOULD include a
human-readable explanation of the error.
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6. Atom Publishing Protocol Documents
6.1. Document Types
This specification defines two kinds of Documents - Category
Documents and Service Documents.
A Category Document (Section 7) contains lists of categories
specified using the "atom:category" element from the Atom Syndication
Format.
A Service Document (Section 8) groups available Collections into
Workspaces.
The namespace name [W3C.REC-xml-names] for either kind of document
is:
http://purl.org/atom/app#
[[anchor8: The namespace name needs to be updated with the final URI
upon publication]]
This specification uses the prefix "app:" for the namespace name.
The prefix "atom:" is used for "http://www.w3.org/2005/Atom", the
namespace name of the Atom Syndication Format [RFC4287]. These
namespace prefixes are not semantically significant.
Atom Publishing Protocol Documents MUST be well-formed XML. This
specification does not define any DTDs for Atom Protocol formats, and
hence does not require them to be "valid" in the sense used by XML.
6.2. Document Extensibility
Unrecognized markup in an Atom Publishing Protocol document is
considered "foreign markup" as defined in Section 6 of [RFC4287].
Such foreign markup can be used anywhere within a Category or Service
Document unless it is explicitly forbidden. Processors that
encounter foreign markup MUST NOT stop processing and MUST NOT signal
an error. Clients SHOULD preserve foreign markup when transmitting
such documents.
The namespace name "http://purl.org/atom/app#" is reserved for
forward compatible revisions of the Category and Service Document
types - this does not exclude the addition of elements and attributes
that might not be recognized by processors conformant to this
specification. Such unrecognized markup from the
"http://purl.org/atom/app#" namespace MUST be treated as foreign
markup.
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[[anchor9: The namespace name needs to be updated with the final URI
upon publication]]
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7. Category Documents
Category Documents contain lists of categories described using the
"atom:category" element from the Atom Syndication Format [RFC4287].
Categories can also appear in Service Documents, where they describe
the categories allowed in a Collection (see Section 8.3.5).
Category Documents are identified with the "application/atomcat+xml"
media type (see Section 16).
7.1. Example
<?xml version="1.0" ?>
<app:categories
xmlns:app="http://purl.org/atom/app#"
xmlns="http://www.w3.org/2005/Atom"
fixed="yes" scheme="http://example.com/cats/big3">
<category term="animal" />
<category term="vegetable" />
<category term="mineral" />
</app:categories>
This Category Document contains three categories, with the terms
"animal", "vegetable", and "mineral". None of the categories use the
'label' attribute defined in [RFC4287]. They all inherit the
"http://example.com/cats/big3" 'scheme' attribute declared on the
app:categories element. Therefore if the "mineral" category were to
appear in an Atom Entry or Feed Document, it would appear as:
<category scheme="http://example.com/cats/big3" term="mineral" />
7.2. Element Definitions
7.2.1. The "app:categories" element
The root of a Category Document is the "app:categories" element. An
app:categories element can contain zero or more "atom:category"
elements from the Atom namespace ("http://www.w3.org/2005/Atom").
An app:category child element that has no "scheme" attribute inherits
the attribute from its app:categories parent. An app:category child
element with an existing "scheme" attribute does not inherit the
"scheme" value of its "app:categories" parent element.
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atomCategory =
element atom:category {
atomCommonAttributes,
attribute term { text },
attribute scheme { atomURI }?,
attribute label { text }?,
undefinedContent
}
appInlineCategories =
element app:categories {
attribute fixed { "yes" | "no" }?,
attribute scheme { atomURI }?,
(atomCategory*)
}
appOutOfLineCategories =
element app:categories {
attribute href { atomURI },
undefinedContent
}
appCategories = appInlineCategories | appOutOfLineCategories
7.2.1.1. Attributes of "app:categories"
The app:categories element can contain a "fixed" attribute, with a
value of either "yes" or "no", indicating whether the list of
categories is a fixed or an open set. The absence of the "fixed"
attribute is equivalent to the presence of a "fixed" attribute with a
value of "no".
Alternatively, the app:categories element MAY contain an "href"
attribute, whose value MUST be an IRI reference identifying a
Category Document. If the "href" attribute is provided, the app:
categories element MUST be empty and MUST NOT have the "fixed" or
"scheme" attributes.
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8. Service Documents
For authoring to commence, a client needs to discover the
capabilities and locations of the available Collections. Service
Documents are designed to support this discovery process.
How Service Documents are discovered is not defined in this
specification.
Service Documents are identified with the "application/atomserv+xml"
media type (see Section 16).
8.1. Workspaces
A Service Document groups a server's Collections into Workspaces.
Operations on Workspaces, such as creation or deletion, are not
defined by this specification. In general, this specification
assigns no meaning to Workspaces; that is, a Workspace does not imply
any specific processing assumptions.
There is no requirement that a server support multiple Workspaces.
In addition, a Collection MAY appear in more than one Workspace.
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8.2. Example
<?xml version="1.0" encoding='utf-8'?>
<service xmlns="http://purl.org/atom/app#"
xmlns:atom="http://www.w3.org/2005/Atom">
<workspace>
<atom:title>Main Site</atom:title>
<collection
href="http://example.org/reilly/main" >
<atom:title>My Blog Entries</atom:title>
<categories
href="http://example.com/cats/forMain.cats" />
</collection>
<collection
href="http://example.org/reilly/pic" >
<atom:title>Pictures</atom:title>
<accept>image/*</accept>
</collection>
</workspace>
<workspace>
<atom:title>Side Bar Blog</atom:title>
<collection
href="http://example.org/reilly/list" >
<atom:title>Remaindered Links</atom:title>
<accept>entry</accept>
<categories fixed="yes">
<atom:category
scheme="http://example.org/extra-cats/"
term="joke" />
<atom:category
scheme="http://example.org/extra-cats/"
term="serious" />
</categories>
</collection>
</workspace>
</service>
The Service Document above describes two Workspaces. The first
Workspace is called "Main Site", and has two Collections called "My
Blog Entries" and "Pictures", whose IRIs are
"http://example.org/reilly/main" and "http://example.org/reilly/pic"
respectively. The "Pictures" Workspace includes an "accept" element
indicating that a client can post image files to the Collection to
create new Media Resources (entries with associated Media Resources
are discussed in Section 9.6).
The second Workspace is called "Side Bar Blog" and has a single
Collection called "Remaindered Links" whose IRI is
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"http://example.org/reilly/list".
Within each of the two Entry collections, the categories element
provides a list of available categories for Member Entries. In the
"My Blog Entries" Collection, the list of available categories is
available through the "href" attribute. The "Side Bar Blog"
Collection provides a category list within the Service Document, but
states the list is fixed, signaling a request from the server that
Entries be POSTed using only those two categories.
8.3. Element Definitions
8.3.1. The "app:service" Element
The root of a Service Document is the "app:service" element.
The "app:service" element is the container for service information
associated with one or more Workspaces. An app:service element MUST
contain one or more app:workspace elements.
namespace app = "http://purl.org/atom/app#"
start = appService
appService =
element app:service {
appCommonAttributes,
( appWorkspace+
& extensionElement* )
}
8.3.2. The "app:workspace" Element
Workspaces are server-defined groups of Collections. The "app:
workspace" element contains zero or more app:collection elements
describing the Collections of resources available for editing.
appWorkspace =
element app:workspace {
appCommonAttributes,
( atomTitle
& appCollection*
& extensionSansTitleElement* )
}
atomTitle = element atom:title { atomTextConstruct }
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8.3.2.1. The "atom:title" Element
The app:workspace element MUST contain one "atom:title" element (as
defined in [RFC4287]), giving a human-readable title for the
Workspace.
8.3.3. The "app:collection" Element
The "app:collection" element describes a Collection. The app:
collection element MAY contain one app:accept element and MAY contain
any number of app:categories elements. The app:collection element
MUST NOT contain more than one app:accept element.
appCollection =
element app:collection {
appCommonAttributes,
attribute href { atomURI },
( atomTitle
& appAccept?
& appCategories*
& extensionSansTitleElement* )
}
8.3.3.1. Usage in Atom Feed Documents
The app:collection element MAY appear as a child of an atom:feed or
atom:source element in an Atom Feed Document. Its content identifies
a Collection by which new Entries can be added to appear in the feed.
The app:collection element is considered foreign markup as defined in
Section 6 of [RFC4287].
8.3.3.2. The "href" Attribute
The app:collection element MUST contain an "href" attribute, whose
value gives the IRI of the Collection.
8.3.3.3. The "atom:title" Element
The app:collection Element MUST contain one "atom:title" element (as
defined in [RFC4287]), giving a human-readable title for the
Collection.
8.3.4. The "app:accept" Element
The "app:accept" element value specifies a comma-separated list of
media-ranges (see [RFC2616]). The list identifies the types of
representations that can be POSTed to the URI of a Collection.
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Whitespace around and between media-range values is insignificant and
MUST be ignored.
The app:accept element is similar to the HTTP Accept request-header
[RFC2616] with the exception that app:accept has no notion of
preference. As a result, the value syntax of app:accept does not use
"accept-params" or "q" arguments as specified in [RFC2616], section
14.1.
The order of media-ranges is not significant. For example, the
following lists are all equivalent:
<app:accept>image/png,image/*</app:accept>
<app:accept>image/*, image/png</app:accept>
<app:accept> image/* </app:accept>
A value of "entry" MAY appear in any list of media-ranges and
indicates that Atom Entry Documents can be POSTed to the Collection.
The value is equivalent to the media type and format parameter
"application/atom+xml;type=entry", as defined in Section 12. If the
accept element exists but is empty, clients SHOULD assume that the
Collection does not support the creation of new Entries. If the
accept element is not present, clients SHOULD treat this as
equivalent to <app:accept>entry</app:accept>.
appAccept =
element app:accept {
appCommonAttributes,
( appTypeValue? )
}
appTypeValue = ( "entry" | media-type |entry-or-media-type )
media-type = xsd:string { pattern = "entry,(.+/.+,?)*" }
entry-or-media-type = xsd:string { pattern = "(.+/.+,?)*" }
8.3.5. The "app:categories" Element
The "app:categories" element provides a list of the categories that
can be applied to the members of a Collection. See Section 7.2.1 for
the detailed definition of app:categories.
The server MAY reject attempts to create or update members whose
categories are not listed in the Collection Document. Collections
that indicate the category set is open SHOULD NOT reject otherwise
acceptable members whose categories are not listed by the Collection.
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The absence of an "app:categories" element means that the category
handling of the Collection is unspecified.
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9. Creating and Editing Resources
9.1. Member URIs
The Member URI allows clients to retrieve, update and delete a Member
Resource using HTTP's GET, PUT and DELETE methods. As their name
indicates, Entry Resources have Atom Entry documents as
representations.
Member URIs appear in two places. They are returned in a Location
header after successful resource creation using POST, as described in
Section 9.2 below. They can also appear in a Collection feed's
entries, as atom:link elements with a link relation of "edit".
A Member Entry SHOULD contain such an atom:link element with a link
relation of "edit", which indicates the Member URI.
9.2. Creating resources with POST
To add members to a Collection, clients send POST requests to the URI
of the Collection.
Successful member creation is indicated with a 201 ("Created")
response code. When the Collection responds with a status code of
201 ("Created"), it SHOULD also return a response body, which MUST be
an Atom Entry Document representing the newly-created resource.
Since the server is free to alter the POSTed Entry, for example by
changing the content of the "atom:id" element, returning the Entry
can be useful to the client, enabling it to correlate the client and
server views of the new Entry.
When a Member Resource is created, its Member Entry URI MUST be
returned in a Location header in the Collections's response.
If the creation request contained an Atom Entry Document, and the
subsequent response from the server contains a Content-Location
header that matches the Location header character-for-character, then
the client is authorized to interpret the response entity as being
the representation of the newly created Entry. Without a matching
Content-Location header the client MUST NOT assume the returned
entity is a complete representation of the created resource.
The request body sent with the POST need not be an Atom Entry. For
example, it might be a picture, or a movie. Collections MAY return a
response with a status code of 415 ("Unsupported Media Type") to
indicate that the media-type of the POSTed entity is not allowed or
supported by the Collection. For a discussion of the issues in
creating such content, see Section 9.6.
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9.2.1. Example
Below, the client sends a POST request containing an Atom Entry
representation to the URI of the Collection:
POST /myblog/entries HTTP/1.1
Host: example.org
User-Agent: Thingio/1.0
Authorization: Basic ZGFmZnk6c2VjZXJldA==
Content-Type: application/atom+xml
Content-Length: nnn
Slug: First Post
<?xml version="1.0" ?>
<entry xmlns="http://www.w3.org/2005/Atom">
<title>Atom-Powered Robots Run Amok</title>
<id>urn:uuid:1225c695-cfb8-4ebb-aaaa-80da344efa6a</id>
<updated>2003-12-13T18:30:02Z</updated>
<author><name>John Doe</name></author>
<content>Some text.</content>
</entry>
The server signals a successful creation with a status code of 201.
The response includes a Location: header indicating the Member Entry
URI of the Atom Entry, and a representation of that Entry in the body
of the response.
HTTP/1.1 201 Created
Date: Fri, 7 Oct 2005 17:17:11 GMT
Content-Length: nnn
Content-Type: application/atom+xml; charset="utf-8"
Location: http://example.org/edit/first-post.atom
<?xml version="1.0"?>
<entry xmlns="http://www.w3.org/2005/Atom">
<title>Atom-Powered Robots Run Amok</title>
<id>urn:uuid:1225c695-cfb8-4ebb-aaaa-80da344efa6a</id>
<updated>2003-12-13T18:30:02Z</updated>
<author><name>John Doe</name></author>
<content>Some text.</content>
<link rel="edit"
href="http://example.org/edit/first-post.atom"/>
</entry>
The Entry created and returned by the Collection might not match the
Entry POSTed by the client. A server MAY change the values of
various elements in the Entry, such as the atom:id, atom:updated and
atom:author values, and MAY choose to remove or add other elements
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and attributes, or change element content and attribute values.
9.3. Updating Resources with PUT
To update a Member Resource, clients send PUT requests to its Member
URI, as specified in [RFC2616].
To avoid unintentional loss of data when editing Member Entries or
Media Link Entries, Atom Protocol clients SHOULD preserve all
metadata that has not been intentionally modified, including unknown
foreign markup as defined in Section 6 of [RFC4287].
9.4. Deleting Resources with DELETE
To delete a Member Resource, clients send DELETE requests to its
Member URI, as specified in [RFC2616]. For a Media Resource, the
deletion of its Media Link Entry SHOULD result in the deletion of the
Media Resource.
9.5. Caching and entity tags
Implementers are advised to pay attention to cache controls, and to
make use of the mechanisms available in HTTP to make editing resource
easier, in particular entity-tags as outlined in
[W3C.NOTE-detect-lost-update-19990510]. Clients are not assured to
receive the most recent representations of Collection Members using
GET if the server is authorizing intermediaries to cache them.
9.5.1. Example
Below, the client creates a Member Entry using POST:
POST /myblog/entries HTTP/1.1
Host: example.org
Authorization: Basic ZGFmZnk6c2VjZXJldA==
Content-Type: application/atom+xml;type=entry
Content-Length: nnn
Slug: First Post
<?xml version="1.0" ?>
<entry xmlns="http://www.w3.org/2005/Atom">
<title>Atom-Powered Robots Run Amok</title>
<id>urn:uuid:1225c695-cfb8-4ebb-aaaa-80da344efa6a</id>
<updated>2007-02-123T17:09:02Z</updated>
<author><name>Captain Lansing</name></author>
<content>It's something moving... solid metal</content>
</entry>
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The server signals a successful creation with a status code of 201,
and returns an ETag header in the response. Because in this case the
server returned a Content-Location and Location header with the same
value, the returned Entry representation can be understood to be
complete (see Section 9.2) and thus the ETag entity value can be also
be used.
HTTP/1.1 201 Created
Date: Fri, 23 Feb 2007 21:17:11 GMT
Content-Length: nnn
Content-Type: application/atom+xml;type=entry
Location: http://example.org/edit/first-post.atom
Content-Location: http://example.org/edit/first-post.atom
ETag: "e180ee84f0671b1"
<?xml version="1.0" ?>
<entry xmlns="http://www.w3.org/2005/Atom">
<title>Atom-Powered Robots Run Amok</title>
<id>urn:uuid:1225c695-cfb8-4ebb-aaaa-80da344efa6a</id>
<updated>2007-02-123T17:09:02Z</updated>
<author><name>Captain Lansing</name></author>
<content>It's something moving... solid metal</content>
</entry>
The client can if it wishes use the returned ETag value to later
construct a "Conditional GET" as defined in [RFC2616]. In this case,
prior to editing the client sends the ETag value for the Member using
the If-None-Match: header.
GET /edit/first-post.atom HTTP/1.1
Host: example.org
Authorization: Basic ZGFmZnk6c2VjZXJldA==
If-None-Match: "e180ee84f0671b1"
If the Entry has not been modified, the server (or an intermediary
cache) can return a status code of 304 (Not Modified). This allows
the client to determine it still has the most recent representation
of the Entry at the time of editing.
HTTP/1.1 304 Not Modified
Date: Sat, 24 Feb 2007 13:17:11 GMT
ETag: "e180ee84f0671b1"
After editing, the client can PUT the updated Entry and send the ETag
entity value in an If-Match header, informing the server to accept
the entry on the condition the entity value sent still matches the
server's.
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PUT /edit/first-post.atom HTTP/1.1
Host: example.org
Authorization: Basic ZGFmZnk6c2VjZXJldA==
Content-Type: application/atom+xml;type=entry
Content-Length: nnn
If-Match: "e180ee84f0671b1"
<?xml version="1.0" ?>
<entry xmlns="http://www.w3.org/2005/Atom">
<title>Atom-Powered Robots Run Amok</title>
<id>urn:uuid:1225c695-cfb8-4ebb-aaaa-80da344efa6a</id>
<updated>2007-02-24T16:34:06Z</updated>
<author><name>Captain Lansing</name></author>
<content>Update: it's a hoax!</content>
</entry>
The server however has since received a more recent update than the
client's, and responds with a status code of 412 (Precondition
Failed).
HTTP/1.1 412 Precondition Failed
Date: Sat, 24 Feb 2007 16:34:11 GMT
ETag: "r34rrt84f0671b22"
This informs the client that the server has a more recent version of
the Entry and will not allow the update.
9.6. Media Resources and Media Link Entries
A client can POST a media type other than application/atom+xml to a
Collection. Such a request always creates two new resources - one
that corresponds to the entity sent in the request, called the Media
Resource, and an associated Member Entry, called the Media Link
Entry. Media Link Entries are represented as Atom Entries and appear
in the Collection.
The Media Link Entry contains the metadata and IRI of the (perhaps
non-textual) Media Resource. The Media Link Entry thus makes the
metadata about the Media Resource separately available for retrieval
and update.
The server can signal the media types it will accept using the
"accept" element in the Service Document as specified in
Section 8.3.4.
Successful responses to creation requests MUST include the URI of the
Media Link Entry in the Location header. The Media Link Entry SHOULD
contain an atom:link element with a link relation of "edit-media"
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that contains the Media Resource IRI. The Media Link Entry MUST have
an "atom:content" element with a "src" attribute. The value of the
"src" attribute is an IRI for the newly created Media Resource. It
is OPTIONAL that the IRI of the "src" attribute on the atom:content
element be the same as the Media Resource IRI. For example, the
"src" attribute value might instead be a link into a static cache or
content distribution network and not the Media Resource IRI.
Implementers are asked to note that according to the requirements of
[RFC4287], Entries, and thus Media Link Entries, MUST contain an
atom:summary element. Upon successful creation of a Media Link
Entry, a server MAY choose to populate the atom:summary element (as
well as any other required elements such as atom:id, atom:author and
atom:title) with content derived from the POSTed entity or from any
other source. A server might not allow a client to modify the server
selected values for these elements.
For resource creation this specification only defines cases where the
POST body has an Atom Entry entity declared as an Atom media type
("application/atom+xml"), or a non-Atom entity declared as a non-Atom
media type. It does not specify any request semantics or server
behavior in the case where the POSTed media-type is "application/
atom+xml" but the body is something other than an Atom Entry. In
particular, what happens on POSTing an Atom Feed Document to a
Collection using the "application/atom+xml" media type is undefined.
The Atom Protocol does not specify a means to create multiple
representations of the same resource (for example a PNG and a JPG of
the same image) on creation or update.
9.6.1. Examples
Below, the client sends a POST request containing a PNG image to the
URI of a Collection that accepts PNG images:
POST /media/ HTTP/1.1
Host: example.org
Content-Type: image/png
Slug: The Beach
Authorization: Basic ZGFmZnk6c2VjZXJldA==
Content-Length: nnn
...binary data...
The server signals a successful creation with a status code of 201.
The response includes a Location header indicating the Member URI of
the Media Link Entry and a representation of that entry in the body
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of the response. The Media Link Entry includes a content element
with a src attribute. It also contains a link with a link relation
of "edit-media", specifying the IRI to be used for modifying the
Media Resource.
HTTP/1.1 201 Created
Date: Fri, 7 Oct 2005 17:17:11 GMT
Content-Length: nnn
Content-Type: application/atom+xml; charset="utf-8"
Location: http://example.org/media/edit/the_beach.atom
<?xml version="1.0"?>
<entry xmlns="http://www.w3.org/2005/Atom">
<title>The Beach</title>
<id>urn:uuid:1225c695-cfb8-4ebb-aaaa-80da344efa6a</id>
<updated>2005-10-07T17:17:08Z</updated>
<author><name>Daffy</name></author>
<summary type="text" />
<content type="image/png"
src="http://media.example.org/the_beach.png"/>
<link rel="edit-media"
href="http://media.example.org/edit/the_beach.png" />
<link rel="edit"
href="http://example.org/media/edit/the_beach.atom" />
</entry>
Later, the client PUTS a new PNG to the URI indicated in the Media
Link Entry's "edit-media" link:
PUT /edit/the_beach.png HTTP/1.1
Host: media.example.org
Content-Type: image/png
Authorization: Basic ZGFmZnk6c2VjZXJldA==
Content-Length: nnn
...binary data...
The server signals a successful update with a status code of 200.
HTTP/1.1 200 Ok
Date: Fri, 8 Oct 2006 17:17:11 GMT
Content-Length: nnn
The client can update the metadata for the picture. First GET the
Media Link Entry:
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GET /media/edit/the_beach.atom HTTP/1.1
Host: example.org
Authorization: Basic ZGFmZnk6c2VjZXJldA==
The Media Link Entry is returned.
HTTP/1.1 200 Ok
Date: Fri, 7 Oct 2005 17:18:11 GMT
Content-Length: nnn
Content-Type: application/atom+xml; charset="utf-8"
<?xml version="1.0"?>
<entry xmlns="http://www.w3.org/2005/Atom">
<title>The Beach</title>
<id>urn:uuid:1225c695-cfb8-4ebb-aaaa-80da344efa6a</id>
<updated>2005-10-07T17:17:08Z</updated>
<author><name>Daffy</name></author>
<summary type="text" />
<content type="image/png"
src="http://media.example.org/the_beach.png"/>
<link rel="edit-media"
href="http://media.example.org/edit/the_beach.png" />
<link rel="edit"
href="http://example.org/media/edit/the_beach.atom" />
</entry>
The metadata can be updated, in this case to add a summary, and then
PUT back to the server.
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PUT /media/edit/the_beach.atom HTTP/1.1
Host: example.org
Authorization: Basic ZGFmZnk6c2VjZXJldA==
Content-Type: application/atom+xml
Content-Length: nnn
<?xml version="1.0"?>
<entry xmlns="http://www.w3.org/2005/Atom">
<title>The Beach</title>
<id>urn:uuid:1225c695-cfb8-4ebb-aaaa-80da344efa6a</id>
<updated>2005-10-07T17:17:08Z</updated>
<author><name>Daffy</name></author>
<summary type="text">
A nice sunset picture over the water.
</summary>
<content type="image/png"
src="http://media.example.org/the_beach.png"/>
<link rel="edit-media"
href="http://media.example.org/edit/the_beach.png" />
<link rel="edit"
href="http://example.org/media/edit/the_beach.atom" />
</entry>
The update was successful.
HTTP/1.1 200 Ok
Date: Fri, 7 Oct 2005 17:19:11 GMT
Content-Length: 0
Multiple media resources can be added to the Collection.
POST /media/ HTTP/1.1
Host: example.org
Content-Type: image/png
Slug: The Pier
Authorization: Basic ZGFmZnk6c2VjZXJldA==
Content-Length: nnn
...binary data...
The resource is created successfully.
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HTTP/1.1 201 Created
Date: Fri, 7 Oct 2005 17:17:11 GMT
Content-Length: nnn
Content-Type: application/atom+xml; charset="utf-8"
Location: http://example.org/media/edit/the_pier.atom
<?xml version="1.0"?>
<entry xmlns="http://www.w3.org/2005/Atom">
<title>The Pier</title>
<id>urn:uuid:1225c695-cfb8-4ebb-aaaa-80da344efe6b</id>
<updated>2005-10-07T17:26:43Z</updated>
<author><name>Daffy</name></author>
<summary type="text" />
<content type="image/png"
src="http://media.example.org/the_pier.png"/>
<link rel="edit-media"
href="http://media.example.org/edit/the_pier.png" />
<link rel="edit"
href="http://example.org/media/edit/the_pier.atom" />
</entry>
The client can now create a new Atom Entry in the blog Entry
Collection that references the two newly created Media Resources.
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POST /blog/ HTTP/1.1
Host: example.org
Content-Type: application/atom+xml
Slug: A day at the beach
Authorization: Basic ZGFmZnk6c2VjZXJldA==
Content-Length: nnn
<?xml version="1.0"?>
<entry xmlns="http://www.w3.org/2005/Atom">
<title>A fun day at the beach</title>
<id>urn:uuid:1225c695-cfb8-4ebb-aaaa-80da344efa6b</id>
<updated>2005-10-07T17:40:02Z</updated>
<author><name>Daffy</name></author>
<content type="xhtml">
<xhtml:div xmlns:xhtml="http://www.w3.org/1999/xhtml">
<xhtml:p>We had a good day at the beach.
<xhtml:img
src="http://media.example.org/the_beach.png"/>
</xhtml:p>
<xhtml:p>Later we walked down to the pier.
<xhtml:img
src="http://media.example.org/the_pier.png"/>
</xhtml:p>
</xhtml:div>
</content>
</entry>
The resource is created successfully.
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HTTP/1.1 200 Ok
Date: Fri, 7 Oct 2005 17:20:11 GMT
Content-Length: nnn
Content-Type: application/atom+xml; charset="utf-8"
Location: http://example.org/blog/atom/a-day-at-the-beach.atom
<?xml version="1.0"?>
<entry xmlns="http://www.w3.org/2005/Atom">
<title>A fun day at the beach</title>
<id>http://example.org/blog/a-day-at-the-beach.xhtml</id>
<updated>2005-10-07T17:43:07Z</updated>
<author><name>Daffy</name></author>
<content type="xhtml">
<xhtml:div xmlns:xhtml="http://www.w3.org/1999/xhtml">
<xhtml:p>We had a good day at the beach.
<xhtml:img
src="http://media.example.org/the_beach.png"/>
</xhtml:p>
<xhtml:p>Later we walked down to the pier.
<xhtml:img
src="http://media.example.org/the_pier.png"/>
</xhtml:p>
</xhtml:div>
</content>
<link rel="edit"
href="http://example.org/blog/edit/a-day-at-the-beach.atom"/>
<link rel="alternate" type="application/xhtml+xml"
href="http://example.org/blog/a-day-at-the-beach.xhtml"/>
</entry>
Note that the returned Entry contains a link with a relation of
"alternate" that points to the associated XHTML page that was
created. This is not required by this specification, but is included
to show the kinds of changes a server may make to an Entry.
9.7. The Slug: Header
Slug is a HTTP entity-header that when accompanying a POST to a
Collection, constitutes a request by the client that its value be
used as part of the URI for the to-be-created Member Resource.
Servers MAY use the value of the Slug header when creating the Member
URI of the newly-created resource, for instance by using some or all
of the words in the value for the last URI segment. Servers MAY also
use the value when creating the atom:id or as the title of a Media
Link Entry (see Section 9.6.).
Servers MAY choose to ignore the Slug entity-header and MAY alter the
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value before using it. For instance, a server might filter out some
characters or replace accented letters with non-accented ones,
replace spaces with underscores, change case, and so on.
9.7.1. Slug: Header syntax
The syntax of this header MUST conform to the augmented BNF grammar
in section 2.1 of the HTTP/1.1 specification [RFC2616]. The TEXT
rule is described in section 2.2 of the same document.
Slug = "Slug" ":" *TEXT
Clients MAY send non-ASCII characters in the Slug entity-header,
which they MUST encode using "encoded-words", as defined in
[RFC2047]. Servers SHOULD treat the slug as [RFC2047] encoded if it
matches the "encoded-words" production.
9.7.2. Example
Here is an example of the Slug: header that uses the encoding rules
of [RFC2047].
POST /myblog/entries HTTP/1.1
Host: example.org
Content-Type: image/png
Slug: =?iso-8859-1?q?The_Beach?=
Authorization: Basic ZGFmZnk6c2VjZXJldA==
Content-Length: nnn
...binary data...
See Section 9.2.1 for an example of the Slug: header applied to the
creation of an Entry Resource.
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10. Listing Collections
Collection Resources MUST provide representations in the form of Atom
Feed documents whose Entries contain the IRIs of the Members in the
Collection. No structural distinction is made between Collection
Feeds and other kinds of Feeds - a Feed might act both as a 'public'
feed for subscription purposes and as a Collection Feed.
Each Entry in the Feed Document SHOULD have an atom:link element with
a relation of "edit" (See Section 11.1).
The Entries in the returned Atom Feed SHOULD be ordered by their
"atom:updated" property, with the most recently updated Entries
coming first in the document order. Since the Atom Syndication
Format states that the value of atom:updated is altered when the
changes to an Entry are something that "the publisher considers
significant", clients SHOULD be constructed in consideration of the
fact that changes which do not result in alterations to the atom:
updated value of an Entry will not affect the position of the Entry
in a Collection. The atom:updated value is not equivalent to the
HTTP Last-Modified: header and can not be used to determine the
freshness of cached responses.
Clients MUST NOT assume that an Atom Entry returned in the Feed is a
full representation of an Entry Resource and SHOULD perform a GET on
the URI of the Member Entry before editing it. See Section 9.5 for a
discussion on the implications of cache control directives when
obtaining entries.
10.1. Collection partial lists
Collections can contain large numbers of resources. A client such as
a web spider or web browser might be overwhelmed if the response to a
GET contained every Entry in a Collection - in turn the server might
also waste bandwidth and processing time on generating a response
that cannot be handled. For this reason, servers MAY respond to
Collection GET requests with a feed document containing a 'partial
list' of the Collection's members, which also links to the next
partial list feed if it exists. The first such partial list returned
MUST contain the most recently updated member resources and MUST have
an atom:link with a "next" relation whose "href" value is the URI of
the next partial list of the Collection. This next partial list will
contain the next most recently updated set of Member Resources (and
an atom:link to the following partial list if it exists).
In addition, partial list feeds MAY contain link elements with "rel"
attribute values of "next", "previous", "first" and "last" that can
be used to navigate through the complete set of entries in the
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Collection.
For instance, suppose a client is supplied the URI
"http://example.org/entries/go" of a Collection of Member entries,
where the server as a matter of policy avoids generating feed
documents containing more than 10 Entries. The Atom Feed document
for the Collection will then represent the first partial list of a
set of 10 linked feed documents. The "first" relation will reference
the initial feed document in the set and the "last" relation
references the final Atom Feed Document in the set. Within each
document, the "next" and "previous" link relations reference the
preceding and subsequent documents.
<feed xmlns="http://www.w3.org/2005/Atom">
<link rel="first"
href="http://example.org/entries/go" />
<link rel="next"
href="http://example.org/entries/2" />
<link rel="last"
href="http://example.org/entries/10" />
...
</feed>
The "next" and "previous" link elements for the partial list feed
located at "http://example.org/entries/2" would look like this:
<feed xmlns="http://www.w3.org/2005/Atom">
<link rel="first"
href="http://example.org/entries/go" />
<link rel="previous"
href="http://example.org/entries/go" />
<link rel="next"
href="http://example.org/entries/3" />
<link rel="last"
href="http://example.org/entries/10" />
...
</feed>
10.2. The "app:edited" Element
The "app:edited" element is a Date construct as defined by [RFC4287]
whose content indicates the last time an Entry was edited. If the
entry has not been edited yet, the content indicates the time it was
created. Atom Entry elements in Collection documents SHOULD contain
one "app:edited" element, and MUST NOT contain more than one.
appEdited = element app:edited ( atomDateConstruct )
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The server SHOULD change the value of this element every time a
Collection Member Resource or an associated Media Resource has been
edited.
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11. Atom Format Link Relation Extensions
11.1. The "edit" Link Relation
This specification adds the value "edit" to the Atom Registry of Link
Relations (see section 7.1 of [RFC4287]). The value of "edit"
specifies that the value of the href attribute is the IRI of an
editable Member Entry. When appearing within an atom:entry, the href
IRI can be used to retrieve, update and delete the resource
represented by that Entry. An atom:entry MUST contain no more than
one "edit" link relation.
11.2. The "edit-media" Link Relation
This specification adds the value "edit-media" to the Atom Registry
of Link Relations (see section 7.1 of [RFC4287]). When appearing
within an atom:entry, the value of the href attribute is an IRI that
can be used to modify a Media Resource associated with that Entry.
An atom:entry element MAY contain zero or more "edit-media" link
relations. An atom:entry MUST NOT contain more than one atom:link
element with a rel attribute value of "edit-media" that has the same
"type" and "hreflang" attribute values. All "edit-media" link
relations in the same Entry reference the same resource. If a client
encounters multiple "edit-media" link relations in an Entry then it
SHOULD choose a link based on the client preferences for "type" and
"hreflang". If a client encounters multiple "edit-media" link
relations in an Entry and has no preference based on the "type" and
"hreflang" attributes then the client SHOULD pick the first "edit-
media" link relation in document order.
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12. The Atom Format Type Parameter
The Atom Syndication Format (RFC 4287) defines the "application/
atom+xml" media type to identify both Atom Feed and Atom Entry
Documents. Implementation experience has demonstrated that Atom Feed
and Entry Documents can have different processing models and that
there are situations where they need to be differentiated. This
document defines an optional "type" parameter used to differentiate
the two types of Atom documents.
12.1. The 'type' parameter
This document defines a new "type" parameter for use with the
"application/atom+xml" media type:
type = "entry" / "feed"
Neither the parameter name nor its value are case sensitive.
The value "entry" indicates that the media type identifies an Atom
Entry Document. The root element of the document MUST be atom:entry.
The value "feed" indicates that the media type identifies an Atom
Feed Document. The root element of the document MUST be atom:feed.
If not specified, the type is assumed to be unspecified, requiring
Atom processors to examine the root element to determine the type of
Atom document.
12.1.1. Conformance
New specifications MAY require that the type parameter be used to
identify the Atom Document type. Producers of Atom Entry Documents
SHOULD use the type parameter regardless of whether or not it is
required. Producers of Atom Feed Documents MAY use the parameter.
Atom processors that do not recognize the "type" parameter MUST
ignore its value and examine the root element to determine the
document type.
Atom processors that do recognize the "type" parameter SHOULD detect
and report inconsistencies between the parameter's value and the
actual type of the document's root element.
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13. Atom Publishing Controls
This specification defines an Atom Format Structured Extension, as
defined in Section 6 of [RFC4287], for publishing control within the
"http://purl.org/atom/app#" namespace.
13.1. The "app:control" Element
namespace app = "http://purl.org/atom/app#"
pubControl =
element app:control {
atomCommonAttributes,
pubDraft?
& extensionElement
}
pubDraft =
element app:draft { "yes" | "no" }
The "app:control" element MAY appear as a child of an atom:entry
which is being created or updated via the Atom Publishing Protocol.
The app:control element MUST appear only once in an Entry. The app:
control element is considered foreign markup as defined in Section 6
of [RFC4287].
The app:control element and its child elements MAY be included in
Atom Feed or Entry Documents.
The app:control element can contain an optional "app:draft" element
as defined below, and can contain extension elements as defined in
Section 6 of [RFC4287].
13.1.1. The "app:draft" Element
The inclusion of the app:draft element represents a request by the
client to control the visibility of a Member Resource. Server
support is optional and thus the app:draft element MAY be ignored by
the server.
The number of app:draft elements in app:control MUST be zero or one.
The content of an app:draft element MUST be one of "yes" or "no". If
the element contains "no" this indicates a client request that the
Member Resource be made publicly visible. If the app:draft element
is not present then servers that support the extension MUST behave as
though an app:draft element containing "no" was sent.
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14. Securing the Atom Publishing Protocol
The Atom Publishing Protocol is based on HTTP. Authentication
requirements for HTTP are covered in Section 11 of [RFC2616].
The use of authentication mechanisms to prevent POSTing or editing by
unknown or unauthorized clients is RECOMMENDED but not required.
When authentication is not used, clients and servers are vulnerable
to trivial spoofing, denial of service and defacement attacks,
however, in some contexts, this is an acceptable risk.
The type of authentication deployed is a local decision made by the
server operator. Clients are likely to face authentication schemes
that vary across server deployments. At a minimum, client and server
implementations MUST be capable of being configured to use HTTP Basic
Authentication [RFC2617] in conjunction with a TLS connection as
specified by [RFC2818]. See [RFC4346] for more information on TLS.
The choice of authentication mechanism will impact interoperability.
The minimum level of security referenced above (Basic Authentication
with TLS) is considered good practice for Internet applications at
the time of publication of this specification and sufficient for
establishing a baseline for interoperability. Implementers are
encouraged to investigate and use alternative mechanisms regarded as
equivalently good or better at the time of deployment. It is
RECOMMENDED that clients be implemented in such a way that allows new
authentication schemes to be deployed.
Because this protocol uses HTTP response status codes as the primary
means of reporting the result of a request, servers are advised to
respond to unauthorized or unauthenticated requests using an
appropriate 4xx HTTP response code (e.g. 401 "Unauthorized" or 403
"Forbidden") in accordance with [RFC2617].
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15. Security Considerations
As an HTTP-based protocol, APP is subject to the security
considerations found in Section 15 of [RFC2616].
15.1. Denial of Service
Atom Publishing server implementations need to take adequate
precautions to ensure malicious clients cannot consume excessive
server resources (CPU, memory, disk, etc).
15.2. Replay Attacks
Atom Publishing server implementations are susceptible to replay
attacks. Specifically, this specification does not define a means of
detecting duplicate requests. Accidentally sent duplicate requests
are indistinguishable from intentional and malicious replay attacks.
15.3. Spoofing Attacks
Atom Publishing implementations are susceptible to a variety of
spoofing attacks. Malicious clients may send Atom Entries containing
inaccurate information anywhere in the document.
15.4. Linked Resources
Atom Feed and Entry documents can contain XML External Entities as
defined in Section 4.2.2 of [W3C.REC-xml]. Atom implementations are
not required to load external entities. External entities are
subject to the same security concerns as any network operation and
can alter the semantics of an Atom document. The same issues exist
for resources linked to by Atom elements such as atom:link and atom:
content.
15.5. Digital Signatures and Encryption
Atom Entry Documents sent to a server might contain XML Digital
Signatures [W3C.REC-xmldsig-core] and might be encrypted using XML
Encryption [W3C.REC-xmlenc-core] as specified in Section 5 of
[RFC4287].
Servers are allowed to modify received resource representations in
ways that can invalidate signatures covering those representations.
15.6. URIs and IRIs
Atom Publishing Protocol implementations handle URIs and IRIs. See
Section 7 of [RFC3986] and Section 8 of [RFC3987].
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16. IANA Considerations
16.1. Content-type registration for 'application/atomserv+xml'
An Atom Publishing Protocol Service Document, when serialized as XML
1.0, can be identified with the following media type:
MIME media type name: application
MIME subtype name: atomsvc+xml
Mandatory parameters: None.
Optional parameters:
"charset": This parameter has identical semantics to the charset
parameter of the "application/xml" media type as specified in
[RFC3023].
Encoding considerations: Identical to those of "application/xml" as
described in [RFC3023], section 3.2.
Security considerations: As defined in this specification.
[[anchor30: update upon publication]]
In addition, as this media type uses the "+xml" convention, it
shares the same security considerations as described in [RFC3023],
section 10.
Interoperability considerations: There are no known interoperability
issues.
Published specification: This specification. [[anchor31: update upon
publication]]
Applications that use this media type: No known applications
currently use this media type.
Additional information:
Magic number(s): As specified for "application/xml" in [RFC3023],
section 3.2.
File extension: .atomsvc
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Fragment identifiers: As specified for "application/xml" in
[RFC3023], section 5.
Base URI: As specified in [RFC3023], section 6.
Macintosh File Type code: TEXT
Person and email address to contact for further information: Joe
Gregorio <joe@bitworking.org>
Intended usage: COMMON
Author/Change controller: This specification's author(s).
[[anchor32: update upon publication]]
16.2. Content-type registration for 'application/atomcat+xml'
An Atom Publishing Protocol Category Document, when serialized as XML
1.0, can be identified with the following media type:
MIME media type name: application
MIME subtype name: atomcat+xml
Mandatory parameters: None.
Optional parameters:
"charset": This parameter has identical semantics to the charset
parameter of the "application/xml" media type as specified in
[RFC3023].
Encoding considerations: Identical to those of "application/xml" as
described in [RFC3023], section 3.2.
Security considerations: As defined in this specification.
[[anchor33: update upon publication]]
In addition, as this media type uses the "+xml" convention, it
shares the same security considerations as described in [RFC3023],
section 10.
Interoperability considerations: There are no known interoperability
issues.
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Published specification: This specification. [[anchor34: update upon
publication]]
Applications that use this media type: No known applications
currently use this media type.
Additional information:
Magic number(s): As specified for "application/xml" in [RFC3023],
section 3.2.
File extension: .atomcat
Fragment identifiers: As specified for "application/xml" in
[RFC3023], section 5.
Base URI: As specified in [RFC3023], section 6.
Macintosh File Type code: TEXT
Person and email address to contact for further information: Joe
Gregorio <joe@bitworking.org>
Intended usage: COMMON
Author/Change controller: This specification's author(s).
[[anchor35: update upon publication]]
16.3. Header field registration for 'SLUG'
Header field: SLUG
Applicable protocol: http [RFC2616]
Status: standard.
Author/Change controller: IETF (iesg@ietf.org) Internet Engineering
Task Force
Specification document(s): draft-ietf-atompub-protocol-13.txt
([[anchor36: update on rfc number assignment]])
Related information:
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16.4. The Link Relation registration "edit"
Attribute Value: edit
Description: An IRI of an editable Member Entry. When appearing
within an atom:entry, the href IRI can be used to retrieve, update
and delete the resource represented by that Entry.
Expected display characteristics: Undefined; this relation can be
used for background processing or to provide extended
functionality without displaying its value.
Security considerations: Automated agents should take care when this
relation crosses administrative domains (e.g., the URI has a
different authority than the current document).
16.5. The Link Relation registration "edit-media"
Attribute Value: edit-media
Description: An IRI of an editable Media Resource. When appearing
within an atom:entry, the href IRI can be used to retrieve, update
and delete the Media Resource associated with that Entry.
Expected display characteristics: Undefined; this relation can be
used for background processing or to provide extended
functionality without displaying its value.
Security considerations: Automated agents should take care when this
relation crosses administrative domains (e.g., the URI has a
different authority than the current document).
16.6. The Atom Format Media Type Parameter
IANA is requested to add a reference to this specification in the
'application/atom+xml' media type registration.
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17. References
17.1. Normative References
[RFC2047] Moore, K., "MIME (Multipurpose Internet Mail Extensions)
Part Three: Message Header Extensions for Non-ASCII Text",
RFC 2047, November 1996.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
[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.
[RFC3023] Murata, M., St. Laurent, S., and D. Kohn, "XML Media
Types", RFC 3023, January 2001.
[RFC3986] Berners-Lee, T., Fielding, R., and L. Masinter, "Uniform
Resource Identifier (URI): Generic Syntax", STD 66,
RFC 3986, January 2005.
[RFC3987] Duerst, M. and M. Suignard, "Internationalized Resource
Identifiers (IRIs)", RFC 3987, January 2005.
[RFC4287] Nottingham, M. and R. Sayre, "The Atom Syndication
Format", RFC 4287, December 2005.
[RFC4346] Dierks, T. and E. Rescorla, "The Transport Layer Security
(TLS) Protocol Version 1.1", RFC 4346, April 2006.
[W3C.REC-xml]
Yergeau, F., Paoli, J., Bray, T., Sperberg-McQueen, C.,
and E. Maler, "Extensible Markup Language (XML) 1.0
(Fourth Edition)", World Wide Web Consortium
Recommendation REC-xml-20060816, August 2006,
<http://www.w3.org/TR/2006/REC-xml-20060816>.
[W3C.REC-xml-infoset]
Cowan, J. and R. Tobin, "XML Information Set (Second
Edition)", World Wide Web Consortium Recommendation REC-
xml-infoset-20040204, February 2004,
<http://www.w3.org/TR/2004/REC-xml-infoset-20040204>.
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[W3C.REC-xml-names]
Hollander, D., Bray, T., Tobin, R., and A. Layman,
"Namespaces in XML 1.0 (Second Edition)", World Wide Web
Consortium Recommendation REC-xml-names-20060816,
August 2006,
<http://www.w3.org/TR/2006/REC-xml-names-20060816>.
[W3C.REC-xmlbase-20010627]
Marsh, J., "XML Base", W3C REC W3C.REC-xmlbase-20010627,
June 2001.
[W3C.REC-xmldsig-core]
Solo, D., Reagle, J., and D. Eastlake, "XML-Signature
Syntax and Processing", World Wide Web Consortium
Recommendation REC-xmldsig-core-20020212, February 2002,
<http://www.w3.org/TR/2002/REC-xmldsig-core-20020212>.
[W3C.REC-xmlenc-core]
Eastlake, D. and J. Reagle, "XML Encryption Syntax and
Processing", World Wide Web Consortium Recommendation REC-
xmlenc-core-20021210, December 2002,
<http://www.w3.org/TR/2002/REC-xmlenc-core-20021210>.
17.2. Informative References
[RFC2818] Rescorla, E., "HTTP Over TLS", RFC 2818, May 2000.
[RNC] Clark, J., "RELAX NG Compact Syntax", December 2001, <http
://www.oasis-open.org/committees/relax-ng/
compact-20021121.html>.
[W3C.NOTE-detect-lost-update-19990510]
Nielsen, H. and D. LaLiberte, "Editing the Web: Detecting
the Lost Update Problem Using Unreserved Checkout", World
Wide Web Consortium NOTE NOTE-detect-lost-update,
May 1999, <http://www.w3.org/1999/04/Editing/>.
[W3C.REC-webarch-20041215]
Walsh, N. and I. Jacobs, "Architecture of the World Wide
Web, Volume One", W3C REC REC-webarch-20041215,
December 2004.
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URIs
[1] <http://www.imc.org/atom-protocol/index.html>
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Appendix A. Contributors
The content and concepts within are a product of the Atom community
and the Atompub Working Group.
[[anchor40: chairs to compile a contribution list for 1.0 --dehora]]
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Appendix B. RELAX NG Compact Schema
This appendix is informative.
The Relax NG schema explicitly excludes elements in the Atom Protocol
namespace which are not defined in this revision of the
specification. Requirements for Atom Protocol processors
encountering such markup are given in Section 6.2 and Section 6.3 of
[RFC4287].
The Schema for Service Documents:
# -*- rnc -*-
# RELAX NG Compact Syntax Grammar for the Atom Protocol
namespace app = "http://purl.org/atom/app#"
namespace atom = "http://www.w3.org/2005/Atom"
namespace xsd = "http://www.w3.org/2001/XMLSchema"
namespace xhtml = "http://www.w3.org/1999/xhtml"
namespace local = ""
start = appService
# common:attrs
atomURI = text
appCommonAttributes =
attribute xml:base { atomURI }?,
attribute xml:lang { atomLanguageTag }?,
undefinedAttribute*
atomCommonAttributes = appCommonAttributes
undefinedAttribute =
attribute * - (xml:base | xml:lang | local:*) { text }
atomLanguageTag = xsd:string {
pattern = "[A-Za-z]{1,8}(-[A-Za-z0-9]{1,8})*"
}
atomDateConstruct =
appCommonAttributes,
xsd:dateTime
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# app:service
appService =
element app:service {
appCommonAttributes,
( appWorkspace+
& extensionElement* )
}
# app:workspace
appWorkspace =
element app:workspace {
appCommonAttributes,
( atomTitle
& appCollection*
& extensionSansTitleElement* )
}
atomTitle = element atom:title { atomTextConstruct }
# app:collection
appCollection =
element app:collection {
appCommonAttributes,
attribute href { atomURI },
( atomTitle
& appAccept?
& appCategories*
& extensionSansTitleElement* )
}
# app:categories
atomCategory =
element atom:category {
atomCommonAttributes,
attribute term { text },
attribute scheme { atomURI }?,
attribute label { text }?,
undefinedContent
}
appInlineCategories =
element app:categories {
attribute fixed { "yes" | "no" }?,
attribute scheme { atomURI }?,
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(atomCategory*)
}
appOutOfLineCategories =
element app:categories {
attribute href { atomURI },
undefinedContent
}
appCategories = appInlineCategories | appOutOfLineCategories
# app:accept
appAccept =
element app:accept {
appCommonAttributes,
( appTypeValue? )
}
appTypeValue = ( "entry" | media-type |entry-or-media-type )
media-type = xsd:string { pattern = "entry,(.+/.+,?)*" }
entry-or-media-type = xsd:string { pattern = "(.+/.+,?)*" }
# above is an approximation, rnc doesn't support interleaved text
# Simple Extension
simpleSansTitleExtensionElement =
element * - (app:*|atom:title) {
text
}
simpleExtensionElement =
element * - (app:*) {
text
}
# Structured Extension
structuredSansTitleExtensionElement =
element * - (app:*|atom:title) {
(attribute * { text }+,
(text|anyElement)*)
| (attribute * { text }*,
(text?, anyElement+, (text|anyElement)*))
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}
structuredExtensionElement =
element * - (app:*) {
(attribute * { text }+,
(text|anyElement)*)
| (attribute * { text }*,
(text?, anyElement+, (text|anyElement)*))
}
# Other Extensibility
extensionSansTitleElement =
simpleSansTitleExtensionElement|structuredSansTitleExtensionElement
extensionElement =
simpleExtensionElement | structuredExtensionElement
undefinedContent = (text|anyForeignElement)*
# Extensions
anyElement =
element * {
(attribute * { text }
| text
| anyElement)*
}
anyForeignElement =
element * - app:* {
(attribute * { text }
| text
| anyElement)*
}
atomPlainTextConstruct =
atomCommonAttributes,
attribute type { "text" | "html" }?,
text
atomXHTMLTextConstruct =
atomCommonAttributes,
attribute type { "xhtml" },
xhtmlDiv
atomTextConstruct = atomPlainTextConstruct | atomXHTMLTextConstruct
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anyXHTML = element xhtml:* {
(attribute * { text }
| text
| anyXHTML)*
}
xhtmlDiv = element xhtml:div {
(attribute * { text }
| text
| anyXHTML)*
}
# EOF
The Schema for Category Documents:
# -*- rnc -*-
# RELAX NG Compact Syntax Grammar for the Atom Protocol
namespace app = "http://purl.org/atom/app#"
namespace atom = "http://www.w3.org/2005/Atom"
namespace xsd = "http://www.w3.org/2001/XMLSchema"
namespace local = ""
start = appCategories
atomCommonAttributes =
attribute xml:base { atomURI }?,
attribute xml:lang { atomLanguageTag }?,
undefinedAttribute*
undefinedAttribute =
attribute * - (xml:base | xml:lang | local:*) { text }
atomURI = text
atomLanguageTag = xsd:string {
pattern = "[A-Za-z]{1,8}(-[A-Za-z0-9]{1,8})*"
}
atomCategory =
element atom:category {
atomCommonAttributes,
attribute term { text },
attribute scheme { atomURI }?,
attribute label { text }?,
undefinedContent
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}
appInlineCategories =
element app:categories {
attribute fixed { "yes" | "no" }?,
attribute scheme { atomURI }?,
(atomCategory*)
}
appOutOfLineCategories =
element app:categories {
attribute href { atomURI },
(empty)
}
appCategories = appInlineCategories | appOutOfLineCategories
# Extensibility
undefinedContent = (text|anyForeignElement)*
anyElement =
element * {
(attribute * { text }
| text
| anyElement)*
}
anyForeignElement =
element * - atom:* {
(attribute * { text }
| text
| anyElement)*
}
# EOF
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Appendix C. Revision History
[[anchor42: This section to be removed upon publication.]]
draft-ietf-atompub-protocol-14: typos; removed "The language context
is only significant for elements and attributes declared to be
"Language-Sensitive" by this specification. "; "Successful member
creation is normally indicated with a 201 ("Created") response code."
removed "normally" from that sentence (9.2); Added "Media Link
Entries are represented as Atom Entries and appear in the
Collection." to 9.6; said that an app:accept value of "entry" is
equivalent to "application/atom+xml;type=entry"; double-check spec
terms; Member Entry Resource -> Entry Resource; Added MLE, Entry
Resource and Media Resource terms defs; 6.1 para split; 10.1
collection paging, rewrote for clarity; 13.1.1 app:edited rewrote for
clarity/conflict; text for GETting entries and cache handling; 4:
Typo: "And Media Resources IRIs", s/Resources/Resource/; consensus
call: application/atomsvc+xml, extension is .atomsvc; DRY app:
categories; make it clear the app:draft support is optional whether
or not the value is sent; 9.2: put related ideas together into
paragraphs.; 10: partial list editing; security: use elharos text;
app:edited: tweak text suplied by ari; create a section for
workspaces and move the descriptive text there; Moved rfc2818 to non-
normative references. Added the W3C note on lost updates as a
reference.
draft-ietf-atompub-protocol-13: Added Lisa's verbiage. Folded in
James' Atom Format media type 'type' parameter spec. Updated
document references to be more consistent, added URLs to some, and
shortened up their anchors. Debugged rnc.
draft-ietf-atompub-protocol-11: Parts of PaceAppEdited.
PaceSecurityConsiderationsRevised.
draft-ietf-atompub-protocol-10: PaceRemoveTitleHeader2,
PaceSlugHeader4, PaceOnlyMemberURI,PaceOneAppNamespaceOnly,
PaceAppCategories, PaceExtendIntrospection,
UseElementsForAppCollectionTitles3, renamed Introspection to Service,
lots of good editorials suggestions, updated media example with slug,
moved xml conventions to convention sections, renamed XMl related
Conventions to Atom Publishing Protocol Documents, added auth header
to examples, consolidated definition of all resource types into the
model section, added IANA reg info for application/atomcat+xml.
draft-ietf-atompub-protocol-09: PaceWorkspaceMayHaveCollections,
PaceMediaEntries5,
http://www.imc.org/atom-protocol/mail-archive/msg05322.html, and
http://www.imc.org/atom-protocol/mail-archive/msg05272.html
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draft-ietf-atompub-protocol-08: added infoset ref; added wording re
IRI/URI; fixed URI/IRI ; next/previous fixed as per Atom
LinkRelations Attribute
(http://www.imc.org/atom-protocol/mail-archive/msg04095.html);
incorporated: PaceEditLinkMustToMay; PaceMissingDraftHasNoMeaning,
PaceRemoveMemberTypeMust, PaceRemoveMemberTypePostMust,
PaceTitleHeaderOnlyInMediaCollections, PacePreserveForeignMarkup,
PaceClarifyTitleHeader, PaceClarifyMediaResourceLinks,
PaceTwoPrimaryCollections;
draft-ietf-atompub-protocol-07: updated Atom refs to RFC4287;
incorporated PaceBetterHttpResponseCode;
PaceClarifyCollectionAndDeleteMethodByWritingLessInsteadOfMore;
PaceRemoveAcceptPostText; PaceRemoveListTemplate2;
PaceRemoveRegistry; PaceRemoveWhoWritesWhat;
PaceSimplifyClarifyBetterfyRemoveBogusValidityText;
PaceCollectionOrderSignificance; PaceFixLostIntrospectionText;
PaceListPaging; PaceCollectionControl; element typo in Listing
collections para3 (was app:member-type, not app:list-template);
changed post atom entry example to be valid. Dropped inline use of
'APP'. Removed nested diagram from section 4. Added ed notes in the
security section.
draft-ietf-atompub-protocol-06 - Removed: Robert Sayre from the
contributors section per his request. Added in
PaceCollectionControl. Fixed all the {daterange} verbage and
examples so they all use a dash. Added full rnc schema. Collapsed
Introspection and Collection documents into a single document.
Removed {dateRange} queries. Renamed search to list. Moved
discussion of media and entry collection until later in the document
and tied the discussion to the Introspection element app:member-type.
draft-ietf-atompub-protocol-05 - Added: Contributors section. Added:
de hOra to editors. Fixed: typos. Added diagrams and description to
model section. Incorporates PaceAppDocuments, PaceAppDocuments2,
PaceSimplifyCollections2 (large-sized chunks of it anyhow: the
notions of Entry and Generic resources, the section 4 language on the
Protocol Model, 4.1 through 4.5.2, the notion of a Collection
document, as in Section 5 through 5.3, Section 7 "Collection
resources", Selection resources (modified from pace which talked
about search); results in major mods to Collection Documents, Section
9.2 "Title: Header" and brokeout para to section 9.1 Editing Generic
Resources). Added XML namespace and language section. Some cleanup
of front matter. Added Language Sensitivity to some attributes.
Removed resource descriptions from terminology. Some juggling of
sections. See:
http://www.imc.org/atom-protocol/mail-archive/msg01812.html.
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draft-ietf-atompub-protocol-04 - Add ladder diagrams, reorganize, add
SOAP interactions
draft-ietf-atompub-protocol-03 - Incorporates PaceSliceAndDice3 and
PaceIntrospection.
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 its purpose.
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.
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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 its 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 its own section. Added
the Revision History section. Added more to the warning that the
example URIs are not normative.
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Authors' Addresses
Joe Gregorio (editor)
IBM
4205 South Miama Blvd.
Research Triangle Park, NC 27709
US
Phone: +1 919 272 3764
Email: joe@bitworking.org
URI: http://ibm.com/
Bill de hOra (editor)
Propylon Ltd.
45 Blackbourne Square, Rathfarnham Gate
Dublin, Dublin D14
IE
Phone: +353-1-4927444
Email: bill.dehora@propylon.com
URI: http://www.propylon.com/
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Full Copyright Statement
Copyright (C) The IETF Trust (2007).
This document is subject to the rights, licenses and restrictions
contained in BCP 78, and except as set forth therein, the authors
retain all their rights.
This document and the information contained herein are provided on an
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