The Hypertext Transfer Protocol (HTTP) Status Code 308 (Permanent Redirect)
draft-reschke-http-status-308-05
The information below is for an old version of the document.
| Document | Type |
This is an older version of an Internet-Draft that was ultimately published as RFC 7238.
|
|
|---|---|---|---|
| Author | Julian Reschke | ||
| Last updated | 2012-03-07 (Latest revision 2012-02-13) | ||
| RFC stream | Internet Engineering Task Force (IETF) | ||
| Formats | |||
| Reviews | |||
| Stream | WG state | (None) | |
| Document shepherd | (None) | ||
| IESG | IESG state | Became RFC 7238 (Experimental) | |
| Consensus boilerplate | Unknown | ||
| Telechat date |
(None)
Needs a YES. |
||
| Responsible AD | Peter Saint-Andre | ||
| IESG note | |||
| Send notices to | julian.reschke@greenbytes.de, cyrus@daboo.name, draft-reschke-http-status-308@tools.ietf.org |
draft-reschke-http-status-308-05
Network Working Group J. Reschke
Internet-Draft greenbytes
Intended status: Experimental February 14, 2012
Expires: August 17, 2012
The Hypertext Transfer Protocol (HTTP) Status Code 308 (Permanent
Redirect)
draft-reschke-http-status-308-05
Abstract
This document specifies the additional HyperText Transfer Protocol
(HTTP) Status Code 308 (Permanent Redirect).
Editorial Note (To be removed by RFC Editor before publication)
Distribution of this document is unlimited. Although this is not a
work item of the HTTPbis Working Group, comments should be sent to
the Hypertext Transfer Protocol (HTTP) mailing list at
ietf-http-wg@w3.org [1], which may be joined by sending a message
with subject "subscribe" to ietf-http-wg-request@w3.org [2].
Discussions of the HTTPbis Working Group are archived at
<http://lists.w3.org/Archives/Public/ietf-http-wg/>.
XML versions, latest edits, and the issues list for this document are
available from
<http://greenbytes.de/tech/webdav/#draft-reschke-http-status-308>.
Test cases related to redirection in general and the status code 308
in particular can be found at
<http://greenbytes.de/tech/tc/httpredirects/#l-308>.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet-
Drafts is at http://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
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This Internet-Draft will expire on August 17, 2012.
Copyright Notice
Copyright (c) 2012 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents
(http://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents
carefully, as they describe your rights and restrictions with respect
to this document. Code Components extracted from this document must
include Simplified BSD License text as described in Section 4.e of
the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Notational Conventions . . . . . . . . . . . . . . . . . . . . 3
3. 308 Permanent Redirect . . . . . . . . . . . . . . . . . . . . 3
4. Deployment Considerations . . . . . . . . . . . . . . . . . . . 4
5. Security Considerations . . . . . . . . . . . . . . . . . . . . 5
6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . . 5
7. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 5
8. Normative References . . . . . . . . . . . . . . . . . . . . . 5
Appendix A. Implementations (to be removed by RFC Editor
before publication) . . . . . . . . . . . . . . . . . 6
Appendix B. Change Log (to be removed by RFC Editor before
publication) . . . . . . . . . . . . . . . . . . . . . 6
B.1. Since draft-reschke-http-status-308-00 . . . . . . . . . . 6
B.2. Since draft-reschke-http-status-308-01 . . . . . . . . . . 6
B.3. Since draft-reschke-http-status-308-02 . . . . . . . . . . 7
B.4. Since draft-reschke-http-status-308-03 . . . . . . . . . . 7
B.5. Since draft-reschke-http-status-308-04 . . . . . . . . . . 7
Appendix C. Resolved issues (to be removed by RFC Editor
before publication) . . . . . . . . . . . . . . . . . 7
C.1. missingconsiderations . . . . . . . . . . . . . . . . . . . 7
Appendix D. Open issues (to be removed by RFC Editor prior to
publication) . . . . . . . . . . . . . . . . . . . . . 7
D.1. edit . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
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1. Introduction
HTTP defines a set of status codes for the purpose of redirecting a
request to a different URI ([RFC3986]). The history of these status
codes is summarized in Section 7.3 of
[draft-ietf-httpbis-p2-semantics], which also classifies the existing
status codes into four categories.
The first of these categories contains the status codes 301 (Moved
Permanently), 302 (Found), and 307 (Temporary Redirect), which can be
classified as below:
+-------------------------------------------+-----------+-----------+
| | Permanent | Temporary |
+-------------------------------------------+-----------+-----------+
| Allows changing the request method from | 301 | 302 |
| POST to GET | | |
| Does not allow changing the request | - | 307 |
| method from POST to GET | | |
+-------------------------------------------+-----------+-----------+
Section 7.3.8 of [draft-ietf-httpbis-p2-semantics] states that HTTP
does not define a permanent variant of status code 307; this
specification adds the status code 308, defining this missing variant
(Section 3).
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].
3. 308 Permanent Redirect
The target resource has been assigned a new permanent URI and any
future references to this resource SHOULD use one of the returned
URIs. Clients with link editing capabilities ought to automatically
re-link references to the effective request URI (Section 4.3 of
[draft-ietf-httpbis-p1-messaging]) to one or more of the new
references returned by the server, where possible.
Caches MAY use a heuristic (see [draft-ietf-httpbis-p6-cache],
Section 2.3.1.1) to determine freshness for 308 responses.
The new permanent URI SHOULD be given by the Location field in the
response ([draft-ietf-httpbis-p2-semantics], Section 9.5). A
response payload can contain a short hypertext note with a hyperlink
to the new URI(s).
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4. Deployment Considerations
Section 4 of [draft-ietf-httpbis-p2-semantics] requires recipients to
treat unknown 3xx status codes the same way as status code 300
Multiple Choices ([draft-ietf-httpbis-p2-semantics], Section 7.3.1).
Thus, servers will not be able to rely on automatic redirection
happening similar to status codes 301, 302, or 307.
Therefore, initial use of status code 308 will be restricted to cases
where the server has sufficient confidence in the clients
understanding the new code, or when a fallback to the semantics of
status code 300 is not problematic.
Note that many existing HTML-based user agents will emulate a refresh
when encountering an HTML <meta> refresh directive. This can be used
as another fallback. For example:
Client request:
GET / HTTP/1.1
Host: example.com
Server response:
HTTP/1.1 308 Permanent Redirect
Content-Type: text/html; charset=UTF-8
Location: http://example.com/new
Content-Length: 454
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN"
"http://www.w3.org/TR/html4/strict.dtd">
<html>
<head>
<title>Permanent Redirect</title>
<meta http-equiv="refresh"
content="0; url=http://example.com/new">
</head>
<body>
<p>
The document has been moved to
<a href="http://example.com/new"
>http://example.com/new</a>.
</p>
</body>
</html>
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5. Security Considerations
All security considerations that apply to HTTP redirects apply to the
308 status code as well (see Section 11 of
[draft-ietf-httpbis-p2-semantics]).
6. IANA Considerations
The registration below shall be added to the HTTP Status Code
Registry (defined in Section 4.2 of [draft-ietf-httpbis-p2-semantics]
and located at <http://www.iana.org/assignments/http-status-codes>):
+-------+--------------------+---------------------------------+
| Value | Description | Reference |
+-------+--------------------+---------------------------------+
| 308 | Permanent Redirect | Section 3 of this specification |
+-------+--------------------+---------------------------------+
7. Acknowledgements
The definition for the new status code 308 re-uses text from the
HTTP/1.1 definitions of status codes 301 and 307.
Furthermore, thanks to Cyrus Daboo, Bjoern Hoehrmann, Subramanian
Moonesamy, and Peter Saint-Andre for feedback on this document.
8. Normative References
[RFC2119] Bradner, S., "Key words for use in
RFCs to Indicate Requirement
Levels", BCP 14, RFC 2119,
March 1997.
[RFC3986] Berners-Lee, T., Fielding, R., and
L. Masinter, "Uniform Resource
Identifier (URI): Generic Syntax",
STD 66, RFC 3986, January 2005.
[draft-ietf-httpbis-p1-messaging] Fielding, R., Ed., Gettys, J.,
Mogul, J., Frystyk, H., Masinter,
L., Leach, P., Berners-Lee, T.,
Lafon, Y., Ed., and J. Reschke,
Ed., "HTTP/1.1, part 1: URIs,
Connections, and Message Parsing",
draft-ietf-httpbis-p1-messaging-18
(work in progress), January 2012.
[draft-ietf-httpbis-p2-semantics] Fielding, R., Ed., Gettys, J.,
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Mogul, J., Frystyk, H., Masinter,
L., Leach, P., Berners-Lee, T.,
Lafon, Y., Ed., and J. Reschke,
Ed., "HTTP/1.1, part 2: Message
Semantics",
draft-ietf-httpbis-p2-semantics-18
(work in progress), January 2012.
[draft-ietf-httpbis-p6-cache] Fielding, R., Ed., Gettys, J.,
Mogul, J., Frystyk, H., Masinter,
L., Leach, P., Berners-Lee, T.,
Lafon, Y., Ed., Nottingham, M.,
Ed., and J. Reschke, Ed.,
"HTTP/1.1, part 6: Caching",
draft-ietf-httpbis-p6-cache-18
(work in progress), January 2012.
[1] <mailto:ietf-http-wg@w3.org>
[2] <mailto:ietf-http-wg-request@w3.org?subject=subscribe>
Appendix A. Implementations (to be removed by RFC Editor before
publication)
Chrome: Feature requested in Chromium Issue 109012
(<http://code.google.com/p/chromium/issues/detail?id=109012>).
Curl (the library): no change was needed (test case:
<https://github.com/bagder/curl/blob/master/tests/data/test1325>).
Firefox: Feature requested in Bugzilla bug 714302
(<https://bugzilla.mozilla.org/show_bug.cgi?id=714302>), patch
available.
Safari: automatically redirects 3xx status codes when a Location
header field is present, but does not preserve the request method.
Appendix B. Change Log (to be removed by RFC Editor before publication)
B.1. Since draft-reschke-http-status-308-00
Updated HTTPbis reference. Added Appendix A. Added and resolved
issue "refresh".
B.2. Since draft-reschke-http-status-308-01
Added URI spec reference.
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B.3. Since draft-reschke-http-status-308-02
Tune HTML example. Expand "Implementations" section. Added and
resolved issue "respformat" (align with new proposed text for 307 in
HTTPbis P2).
B.4. Since draft-reschke-http-status-308-03
Added and resolved issue "uaconfirm".
B.5. Since draft-reschke-http-status-308-04
Added and resolved issue "missingconsiderations". Added request
message to example. Updated the Safari implementation note.
Appendix C. Resolved issues (to be removed by RFC Editor before
publication)
Issues that were either rejected or resolved in this version of this
document.
C.1. missingconsiderations
In Section 3:
Type: change
stpeter@stpeter.im (2012-02-10): According to HTTPbis Part 2, need to
explain the request conditions, interactions with response headers,
and implications for caches. If certain default behavior is assumed,
it would be good to make that explicit.
Resolution (2012-02-13): Added missing caching considerations.
Appendix D. Open issues (to be removed by RFC Editor prior to
publication)
D.1. edit
Type: edit
julian.reschke@greenbytes.de (2011-04-15): Umbrella issue for
editorial fixes/enhancements.
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Author's Address
Julian F. Reschke
greenbytes GmbH
Hafenweg 16
Muenster, NW 48155
Germany
EMail: julian.reschke@greenbytes.de
URI: http://greenbytes.de/tech/webdav/
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