draft-ietf-regext-rdap-partial-response-01.txt   draft-ietf-regext-rdap-partial-response-02.txt 
Registration Protocols Extensions M. Loffredo Registration Protocols Extensions M. Loffredo
Internet-Draft M. Martinelli Internet-Draft M. Martinelli
Intended status: Standards Track IIT-CNR/Registro.it Intended status: Standards Track IIT-CNR/Registro.it
Expires: October 13, 2019 April 11, 2019 Expires: November 28, 2019 May 27, 2019
Registration Data Access Protocol (RDAP) Partial Response Registration Data Access Protocol (RDAP) Partial Response
draft-ietf-regext-rdap-partial-response-01 draft-ietf-regext-rdap-partial-response-02
Abstract Abstract
The Registration Data Access Protocol (RDAP) does not include The Registration Data Access Protocol (RDAP) does not include
capabilities to request partial responses. In fact, according to the capabilities to request partial responses. In fact, according to the
user authorization, the server can only return full responses. user authorization, the server can only return full responses.
Partial responses capability, especially in the case of search Partial responses capability, especially in the case of search
queries, could bring benefits to both clients and servers. This queries, could bring benefits to both clients and servers. This
document describes a RDAP query extension that allows clients to document describes an RDAP query extension that allows clients to
specify their preference for obtaining a partial response. specify their preference for obtaining a partial response.
Status of This Memo Status of This Memo
This Internet-Draft is submitted in full conformance with the This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79. provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet- working documents as Internet-Drafts. The list of current Internet-
Drafts is at https://datatracker.ietf.org/drafts/current/. Drafts is at https://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress." material or to cite them other than as "work in progress."
This Internet-Draft will expire on October 13, 2019. This Internet-Draft will expire on November 28, 2019.
Copyright Notice Copyright Notice
Copyright (c) 2019 IETF Trust and the persons identified as the Copyright (c) 2019 IETF Trust and the persons identified as the
document authors. All rights reserved. document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents Provisions Relating to IETF Documents
(https://trustee.ietf.org/license-info) in effect on the date of (https://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents publication of this document. Please review these documents
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Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
1.1. Conventions Used in This Document . . . . . . . . . . . . 3 1.1. Conventions Used in This Document . . . . . . . . . . . . 3
2. Approaches to Partial Response Implementation . . . . . . . . 3 2. Approaches to Partial Response Implementation . . . . . . . . 3
3. RDAP Path Segment Specification . . . . . . . . . . . . . . . 5 3. RDAP Path Segment Specification . . . . . . . . . . . . . . . 5
3.1. Subsetting Metadata . . . . . . . . . . . . . . . . . . . 5 3.1. Subsetting Metadata . . . . . . . . . . . . . . . . . . . 5
3.1.1. Representing Subsetting Links . . . . . . . . . . . . 6 3.1.1. Representing Subsetting Links . . . . . . . . . . . . 6
4. Dealing with Relationships . . . . . . . . . . . . . . . . . 7 4. Dealing with Relationships . . . . . . . . . . . . . . . . . 7
5. Basic Field Sets . . . . . . . . . . . . . . . . . . . . . . 7 5. Basic Field Sets . . . . . . . . . . . . . . . . . . . . . . 7
6. RDAP Conformance . . . . . . . . . . . . . . . . . . . . . . 8 6. Negative Answers . . . . . . . . . . . . . . . . . . . . . . 8
7. Implementation Status . . . . . . . . . . . . . . . . . . . . 8 7. RDAP Conformance . . . . . . . . . . . . . . . . . . . . . . 8
7.1. IIT-CNR/Registro.it . . . . . . . . . . . . . . . . . . . 9 8. Implementation Status . . . . . . . . . . . . . . . . . . . . 8
8. Security Considerations . . . . . . . . . . . . . . . . . . . 9 8.1. IIT-CNR/Registro.it . . . . . . . . . . . . . . . . . . . 9
9. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 10 9. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 9
10. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 10 10. Security Considerations . . . . . . . . . . . . . . . . . . . 9
11. References . . . . . . . . . . . . . . . . . . . . . . . . . 10 11. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 10
11.1. Normative References . . . . . . . . . . . . . . . . . . 10 12. References . . . . . . . . . . . . . . . . . . . . . . . . . 10
11.2. Informative References . . . . . . . . . . . . . . . . . 11 12.1. Normative References . . . . . . . . . . . . . . . . . . 10
12.2. Informative References . . . . . . . . . . . . . . . . . 11
Appendix A. Change Log . . . . . . . . . . . . . . . . . . . . . 12 Appendix A. Change Log . . . . . . . . . . . . . . . . . . . . . 12
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 12 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 12
1. Introduction 1. Introduction
The use of partial response in RESTful API ([REST]) design is very The use of partial response in RESTful API ([REST]) design is very
common. The rationale is quite simple: instead of returning objects common. The rationale is quite simple: instead of returning objects
in API responses with all data fields, only a subset is returned. in API responses with all data fields, only a subset is returned.
The benefit is obvious: less data transferred over the network mean The benefit is obvious: less data transferred over the network means
less bandwidth usage, faster server response, less CPU time spent less bandwidth usage, faster server response, less CPU time spent
both on the server and the client, as well as less memory usage on both on the server and the client, as well as less memory usage on
the client. the client.
Several leading APIs providers (e.g. LinkedIn [LINKEDIN], Facebook Several leading APIs providers (e.g. LinkedIn [LINKEDIN], Facebook
[FACEBOOK], Google [GOOGLE]) implement the partial response feature [FACEBOOK], Google [GOOGLE]) implement the partial response feature
by providing an optional query parameter by which users require the by providing an optional query parameter by which users require the
fields they wish to receive. Partial response is also considered a fields they wish to receive. Partial response is also considered a
leading principle by many best practices guidelines in REST APIs leading principle by many best practices guidelines in REST APIs
implementation ([REST-API1], [REST-API2]) in order to improve implementation ([REST-API1], [REST-API2]) in order to improve
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o the client declares explicitly the data fields to get back; o the client declares explicitly the data fields to get back;
o the client declares a name identifying a server pre-defined set of o the client declares a name identifying a server pre-defined set of
data fields. data fields.
The former is more flexible than the latter, because clients can The former is more flexible than the latter, because clients can
specify all the data fields they need. However, it has some specify all the data fields they need. However, it has some
drawbacks: drawbacks:
o Fields have to be declared according to a given syntax. This is a o fields have to be declared according to a given syntax. This is a
simple task when the data structure of the object is flat, but it simple task when the data structure of the object is flat, but it
is much more difficult when the object has a tree structure like is much more difficult when the object has a tree structure like
the one of a JSON object. The presence of arrays and deep nested the one of a JSON object. The presence of arrays and deep nested
objects contribute to complicate both the syntax definition of the objects contributes to complicate both the syntax definition of
query and, consequently, the processing phase on the server side. the query and, consequently, the processing phase on the server
side;
o Clients should perfectly know the returned object to avoid cases o clients should perfectly know the returned data structure to avoid
when the required fields are not compliant with the object data cases when the requested fields are invalid;
structure.
o The request of some fields cannot match the user access levels. o the request of some fields might not match the user access levels.
Clients could put unauthorized fields in their requests and Clients might put unauthorized fields in their requests and
servers should define a strategy for providing a response: to servers should define a strategy for providing a response:
return always an error response or to return a response ignoring returning always an error response or returning a response that
the unauthorized fields. ignores the unauthorized fields.
In addition to those listed above, RDAP responses raise some specific In addition to those listed above, RDAP responses raise some specific
issues: issues:
o Most of the relevant information of the entity object is included o most of the relevant information of the entity object is included
in the jCard but such information cannot be easily selected in the jCard but such information cannot be easily selected
because it is split into the items of a jagged array. because it is split into the items of a jagged array;
o RDAP responses contain some properties providing service o RDAP responses contain some properties providing service
information (e.g. rdapConformance, links, notices, remarks, etc.) information (e.g. rdapConformance, links, notices, remarks, etc.)
which are not normally selected but they are just as important. which are not normally selected but they are just as important.
They could be returned anyway but, in this case, the server would They could be returned anyway but, in this case, the server would
provide unrequested data. provide unrequested data.
As an example compliant to the first approach, the Catnap Query As an example compliant to the first approach, the Catnap Query
Language ([CQL]) is a comprehensive expression language that can be Language ([CQL]) is a comprehensive expression language that can be
used to customize the JSON response of a RESTful web service. The used to customize the JSON response of a RESTful web service. The
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The latter approach seems to facilitate RDAP interoperability. In The latter approach seems to facilitate RDAP interoperability. In
fact, servers can define some basic field sets which, if known to the fact, servers can define some basic field sets which, if known to the
clients, can increase the probability to get a valid response. The clients, can increase the probability to get a valid response. The
usage of field sets lets the query string be less complex. In usage of field sets lets the query string be less complex. In
addition, the definition of pre-defined sets of fields makes easier addition, the definition of pre-defined sets of fields makes easier
to establish the results limits. to establish the results limits.
Finally, considering that there is not a real need for RDAP users to Finally, considering that there is not a real need for RDAP users to
have the maximum flexibility in defining all the possible sets of have the maximum flexibility in defining all the possible sets of
logically connected fields (for example, users interested in domains logically connected fields (e.g. users interested in domains usually
usually need to know the status, the creation date, the expire date need to know the status, the creation date, the expire date of each
of each domain), the latter approach is preferred. domain), the latter approach is preferred.
3. RDAP Path Segment Specification 3. RDAP Path Segment Specification
The path segment defined in this section is an OPTIONAL extension of The path segment defined in this section is an OPTIONAL extension of
search path segments defined in RFC 7482 ([RFC7482]). This document search path segments defined in RFC 7482 ([RFC7482]). This document
defines an RDAP query parameter, "fieldSet", whose value is a string defines an RDAP query parameter, "fieldSet", whose value is a string
identifying a server pre-defined set of fields (Figure 2). identifying a server pre-defined set of fields (Figure 2).
https://example.com/rdap/domains?name=example*.com&fieldSet=afieldset https://example.com/rdap/domains?name=example*.com&fieldSet=afieldset
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* "description": "String" (OPTIONAL) a human-readable description * "description": "String" (OPTIONAL) a human-readable description
of the field set; of the field set;
* "links": "Link[]" (OPTIONAL) an array of links as described in * "links": "Link[]" (OPTIONAL) an array of links as described in
RFC 8288 ([RFC8288]) containing the query string that applies RFC 8288 ([RFC8288]) containing the query string that applies
the field set. the field set.
3.1.1. Representing Subsetting Links 3.1.1. Representing Subsetting Links
An RDAP server MAY use the "links" array of the "subsetting_metadata" An RDAP server MAY use the "links" array of the "subsetting_metadata"
section to provide ready-made references ([RFC8288]) to the available element to provide ready-made references ([RFC8288]) to the available
field sets (Figure 3). Each link represents a reference to an field sets (Figure 3). Each link represents a reference to an
alternate view of the results. alternate view of the results.
{ {
"rdapConformance": [ "rdapConformance": [
"rdap_level_0", "rdap_level_0",
"subsetting_level_0" "subsetting_level_0"
], ],
... ...
"subsetting_metadata": { "subsetting_metadata": {
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for a subset of the full response which gives a basic knowledge of for a subset of the full response which gives a basic knowledge of
each object; each object;
o "full": it contains all the information the server can provide for o "full": it contains all the information the server can provide for
a particular object. a particular object.
The "objectClassName" field is implicitly included in each of the The "objectClassName" field is implicitly included in each of the
above field sets. RDAP providers MAY add any property providing above field sets. RDAP providers MAY add any property providing
service information. service information.
Fields belonging to "brief" and "full" field sets could be returned Fields included in "brief" and "full" field sets could be returned
according to users access levels. according to users access levels.
{ {
"rdapConformance": [ "rdapConformance": [
"rdap_level_0", "rdap_level_0",
], ],
... ...
"domainSearchResults": [ "domainSearchResults": [
{ {
"objectClassName": "domain", "objectClassName": "domain",
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{ {
"objectClassName": "domain", "objectClassName": "domain",
"ldhName": "example2.com" "ldhName": "example2.com"
}, },
... ...
] ]
} }
Figure 4: Example of RDAP response according to the "id" field set Figure 4: Example of RDAP response according to the "id" field set
6. RDAP Conformance 6. Negative Answers
Each request including an unsupported field set SHOULD obtain an HTTP
400 (Bad Request) response code.
Optionally, the response MAY include additional information regarding
the negative answer in the HTTP entity body.
7. RDAP Conformance
Servers returning the "subsetting_metadata" section in their Servers returning the "subsetting_metadata" section in their
responses MUST include "subsetting_level_0" in the rdapConformance responses MUST include "subsetting_level_0" in the rdapConformance
array. array.
7. Implementation Status 8. Implementation Status
NOTE: Please remove this section and the reference to RFC 7942 prior NOTE: Please remove this section and the reference to RFC 7942 prior
to publication as an RFC. to publication as an RFC.
This section records the status of known implementations of the This section records the status of known implementations of the
protocol defined by this specification at the time of posting of this protocol defined by this specification at the time of posting of this
Internet-Draft, and is based on a proposal described in RFC 7942 Internet-Draft, and is based on a proposal described in RFC 7942
([RFC7942]). The description of implementations in this section is ([RFC7942]). The description of implementations in this section is
intended to assist the IETF in its decision processes in progressing intended to assist the IETF in its decision processes in progressing
drafts to RFCs. Please note that the listing of any individual drafts to RFCs. Please note that the listing of any individual
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Furthermore, no effort has been spent to verify the information Furthermore, no effort has been spent to verify the information
presented here that was supplied by IETF contributors. This is not presented here that was supplied by IETF contributors. This is not
intended as, and must not be construed to be, a catalog of available intended as, and must not be construed to be, a catalog of available
implementations or their features. Readers are advised to note that implementations or their features. Readers are advised to note that
other implementations may exist. other implementations may exist.
According to RFC 7942, "this will allow reviewers and working groups According to RFC 7942, "this will allow reviewers and working groups
to assign due consideration to documents that have the benefit of to assign due consideration to documents that have the benefit of
running code, which may serve as evidence of valuable experimentation running code, which may serve as evidence of valuable experimentation
and feedback that have made the implemented protocols more mature. and feedback that have made the implemented protocols more mature.
It is up to the individual working groups to use this information as It is up to the individual working groups to use this information as
they see fit". they see fit".
7.1. IIT-CNR/Registro.it 8.1. IIT-CNR/Registro.it
Responsible Organization: Institute of Informatics and Telematics Responsible Organization: Institute of Informatics and Telematics
of National Research Council (IIT-CNR)/Registro.it of National Research Council (IIT-CNR)/Registro.it
Location: https://rdap.pubtest.nic.it/ Location: https://rdap.pubtest.nic.it/
Description: This implementation includes support for RDAP queries Description: This implementation includes support for RDAP queries
using data from the public test environment of .it ccTLD. using data from .it public test environment.
Level of Maturity: This is a "proof of concept" research Level of Maturity: This is a "proof of concept" research
implementation. implementation.
Coverage: This implementation includes all of the features Coverage: This implementation includes all of the features
described in this specification. described in this specification.
Contact Information: Mario Loffredo, mario.loffredo@iit.cnr.it Contact Information: Mario Loffredo, mario.loffredo@iit.cnr.it
8. Security Considerations 9. IANA Considerations
IANA is requested to register the following value in the RDAP
Extensions Registry:
Extension identifier: subsetting
Registry operator: Any
Published specification: This document.
Contact: IESG <iesg@ietf.org>
Intended usage: This extension describes a best practice for
partial response provisioning.
10. Security Considerations
Search query typically requires more server resources (such as Search query typically requires more server resources (such as
memory, CPU cycles, and network bandwidth) when compared to lookup memory, CPU cycles, and network bandwidth) when compared to lookup
query. This increases the risk of server resource exhaustion and query. This increases the risk of server resource exhaustion and
subsequent denial of service due to abuse. Partial response can subsequent denial of service due to abuse. Partial response can
contribute together with other strategies (e.g. restricting search contribute together with other strategies (e.g. restricting search
functionality, limiting the rate of search requests, truncating and functionality, limiting the rate of search requests, truncating and
paging results) to mitigate this risk. paging results) to mitigate this risk.
Furthermore, partial response can help RDAP operators to regulate Furthermore, partial response can support RDAP operators to implement
access control based on client identification, implemented by HTTP a versatile access control policy through the HTTP authentication
authentication mechanisms as described in RFC 7481 ([RFC7481]). In mechanisms as described in RFC 7481 ([RFC7481]). In fact, RDAP
fact, RDAP operators can follow different, not alternative, operators can follow different, not alternative, approaches to the
approaches to the building of responses according to the user access building of responses according to the user access levels:
levels:
o the list of fields for each set can be different according to the o the list of fields for each set can be different according to the
user access levels; user access levels;
o some field sets could be available only to some users. o some field sets could be available only to some users.
Servers can also define different results limits according to the Servers can also define different results limits according to the
available field sets, so a more flexible truncation strategy can be available field sets, so a more flexible truncation strategy can be
realized. realized.
Therefore, the new query parameter presented in this document Therefore, the new query parameter presented in this document
provides the RDAP operators with a way to implement a secure server provides the RDAP operators with a way to implement a secure server
without penalizing its efficiency. without penalizing its efficiency.
9. IANA Considerations 11. Acknowledgements
This document has no actions for IANA.
10. Acknowledgements
The authors would like to acknowledge Scott Hollenbeck for his The authors would like to acknowledge Scott Hollenbeck for his
contribution to this document. contribution to this document.
11. References 12. References
11.1. Normative References 12.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997, DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>. <https://www.rfc-editor.org/info/rfc2119>.
[RFC7230] Fielding, R., Ed. and J. Reschke, Ed., "Hypertext Transfer [RFC7230] Fielding, R., Ed. and J. Reschke, Ed., "Hypertext Transfer
Protocol (HTTP/1.1): Message Syntax and Routing", Protocol (HTTP/1.1): Message Syntax and Routing",
RFC 7230, DOI 10.17487/RFC7230, June 2014, RFC 7230, DOI 10.17487/RFC7230, June 2014,
<https://www.rfc-editor.org/info/rfc7230>. <https://www.rfc-editor.org/info/rfc7230>.
skipping to change at page 11, line 5 skipping to change at page 11, line 19
[RFC7483] Newton, A. and S. Hollenbeck, "JSON Responses for the [RFC7483] Newton, A. and S. Hollenbeck, "JSON Responses for the
Registration Data Access Protocol (RDAP)", RFC 7483, Registration Data Access Protocol (RDAP)", RFC 7483,
DOI 10.17487/RFC7483, March 2015, DOI 10.17487/RFC7483, March 2015,
<https://www.rfc-editor.org/info/rfc7483>. <https://www.rfc-editor.org/info/rfc7483>.
[RFC8288] Nottingham, M., "Web Linking", RFC 8288, [RFC8288] Nottingham, M., "Web Linking", RFC 8288,
DOI 10.17487/RFC8288, October 2017, DOI 10.17487/RFC8288, October 2017,
<https://www.rfc-editor.org/info/rfc8288>. <https://www.rfc-editor.org/info/rfc8288>.
11.2. Informative References 12.2. Informative References
[CQL] Whitaker, G., "Catnap Query Language Reference", September [CQL] Whitaker, G., "Catnap Query Language Reference", September
2017, <https://github.com/gregwhitaker/catnap/wiki/ 2017, <https://github.com/gregwhitaker/catnap/wiki/
Catnap-Query-Language-Reference>. Catnap-Query-Language-Reference>.
[FACEBOOK] [FACEBOOK]
facebook.com, "facebook for developers - Using the Graph facebook.com, "facebook for developers - Using the Graph
API", July 2017, <https://developers.facebook.com/docs/ API", July 2017, <https://developers.facebook.com/docs/
graph-api/using-graph-api>. graph-api/using-graph-api>.
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Appendix A. Change Log Appendix A. Change Log
00: Initial working group version ported from draft-loffredo-regext- 00: Initial working group version ported from draft-loffredo-regext-
rdap-partial-response-03 rdap-partial-response-03
01: Removed "FOR DISCUSSION" items. Changed the basic field sets 01: Removed "FOR DISCUSSION" items. Changed the basic field sets
from REQUIRED to OPTIONAL. Removed the definition of fields from REQUIRED to OPTIONAL. Removed the definition of fields
included in "brief" field set. Provided a more detailed included in "brief" field set. Provided a more detailed
description of "subsetting_metadata" structure. Removed some description of "subsetting_metadata" structure. Removed some
references. references.
02: Added the "Negative Answers" section. Changed "IANA
Considerations" section.
Authors' Addresses Authors' Addresses
Mario Loffredo Mario Loffredo
IIT-CNR/Registro.it IIT-CNR/Registro.it
Via Moruzzi,1 Via Moruzzi,1
Pisa 56124 Pisa 56124
IT IT
Email: mario.loffredo@iit.cnr.it Email: mario.loffredo@iit.cnr.it
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