RFC 9652 Link-Template September 2024
Nottingham Standards Track [Page]
Stream:
Internet Engineering Task Force (IETF)
RFC:
9652
Category:
Standards Track
Published:
ISSN:
2070-1721
Author:
M. Nottingham

RFC 9652

The Link-Template HTTP Header Field

Abstract

This specification defines the Link-Template HTTP header field, providing a means for describing the structure of a link between two resources so that new links can be generated.

Status of This Memo

This is an Internet Standards Track document.

This document is a product of the Internet Engineering Task Force (IETF). It represents the consensus of the IETF community. It has received public review and has been approved for publication by the Internet Engineering Steering Group (IESG). Further information on Internet Standards is available in Section 2 of RFC 7841.

Information about the current status of this document, any errata, and how to provide feedback on it may be obtained at https://www.rfc-editor.org/info/rfc9652.

Table of Contents

1. Introduction

[URI-TEMPLATE] defines a syntax for templates that, when expanded using a set of variables, results in a URI [URI].

This specification defines a HTTP header field [HTTP] for conveying templates for links in the headers of a HTTP message. It is complimentary to the Link header field defined in Section 3 of [WEB-LINKING], which carries links directly.

1.1. Notational Conventions

The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all capitals, as shown here.

This specification uses the following terms from [STRUCTURED-FIELDS]: List, String, Display String, and Parameter.

3. Security Considerations

The security considerations for the Link header field in [WEB-LINKING] and those for URI Templates [URI-TEMPLATE] apply.

Target attributes that are conveyed via Display Strings can be vulnerable to a wide variety of attacks. See [UNICODE-SECURITY] for advice regarding their handling. Specific advice is not given by this specification since there are a variety of potential use cases for such attributes.

4. IANA Considerations

This specification enters the "Link-Template" field name into the "Hypertext Transfer Protocol (HTTP) Field Name Registry".

Table 1
Field Name Status Reference
Link-Template Permanent This document

5. Normative References

[HTTP]
Fielding, R., Ed., Nottingham, M., Ed., and J. Reschke, Ed., "HTTP Semantics", STD 97, RFC 9110, DOI 10.17487/RFC9110, , <https://www.rfc-editor.org/info/rfc9110>.
[RFC2119]
Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, , <https://www.rfc-editor.org/info/rfc2119>.
[RFC8174]
Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, , <https://www.rfc-editor.org/info/rfc8174>.
[STRUCTURED-FIELDS]
Nottingham, M. and P-H. Kamp, "Structured Field Values for HTTP", RFC 9651, DOI 10.17487/RFC9651, , <https://www.rfc-editor.org/info/rfc9651>.
[UNICODE-SECURITY]
Davis, M. and M. Suignard, "Unicode Security Considerations", Unicode Technical Report #16, , <https://www.unicode.org/reports/tr36/>. Latest version available at <https://www.unicode.org/reports/tr36/>.
[URI]
Berners-Lee, T., Fielding, R., and L. Masinter, "Uniform Resource Identifier (URI): Generic Syntax", STD 66, RFC 3986, DOI 10.17487/RFC3986, , <https://www.rfc-editor.org/info/rfc3986>.
[URI-TEMPLATE]
Gregorio, J., Fielding, R., Hadley, M., Nottingham, M., and D. Orchard, "URI Template", RFC 6570, DOI 10.17487/RFC6570, , <https://www.rfc-editor.org/info/rfc6570>.
[WEB-LINKING]
Nottingham, M., "Web Linking", RFC 8288, DOI 10.17487/RFC8288, , <https://www.rfc-editor.org/info/rfc8288>.

Author's Address

Mark Nottingham
Prahran
Australia