A JSON Meta Application Protocol (JMAP) Subprotocol for WebSocket
RFC 8887
Document | Type | RFC - Proposed Standard (August 2020; No errata) | |
---|---|---|---|
Author | Kenneth Murchison | ||
Last updated | 2020-08-27 | ||
Replaces | draft-murchison-jmap-websocket | ||
Stream | IETF | ||
Formats | plain text html xml pdf htmlized bibtex | ||
Reviews | |||
Stream | WG state | Submitted to IESG for Publication | |
Document shepherd | Jim Fenton | ||
Shepherd write-up | Show (last changed 2019-11-25) | ||
IESG | IESG state | RFC 8887 (Proposed Standard) | |
Action Holders |
(None)
|
||
Consensus Boilerplate | Yes | ||
Telechat date | |||
Responsible AD | Alexey Melnikov | ||
Send notices to | Jim Fenton <fenton@bluepopcorn.net> | ||
IANA | IANA review state | IANA OK - Actions Needed | |
IANA action state | RFC-Ed-Ack |
Internet Engineering Task Force (IETF) K. Murchison Request for Comments: 8887 Fastmail Category: Standards Track August 2020 ISSN: 2070-1721 A JSON Meta Application Protocol (JMAP) Subprotocol for WebSocket Abstract This document defines a binding for the JSON Meta Application Protocol (JMAP) over a WebSocket transport layer. The WebSocket binding for JMAP provides higher performance than the current HTTP binding for JMAP. 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/rfc8887. Copyright Notice Copyright (c) 2020 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 (https://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 2. Conventions Used in This Document 3. Discovering Support for JMAP over WebSocket 4. JMAP Subprotocol 4.1. Authentication 4.2. Handshake 4.3. WebSocket Messages 4.3.1. Handling Invalid Data 4.3.2. JMAP Requests 4.3.3. JMAP Responses 4.3.4. JMAP Request-Level Errors 4.3.5. JMAP Push Notifications 4.4. Examples 5. Security Considerations 5.1. Connection Confidentiality and Integrity 5.2. Non-browser Clients 6. IANA Considerations 6.1. Registration of the WebSocket JMAP Subprotocol 7. References 7.1. Normative References 7.2. Informative References Acknowledgments Author's Address 1. Introduction JMAP [RFC8620] over HTTP [RFC7235] requires that every JMAP API request be authenticated. Depending on the type of authentication used by the JMAP client and the configuration of the JMAP server, authentication could be an expensive operation both in time and resources. In such circumstances, reauthenticating for every JMAP API request may harm performance. The WebSocket [RFC6455] binding for JMAP eliminates this performance hit by authenticating just the WebSocket handshake request and having those credentials remain in effect for the duration of the WebSocket connection. This binding supports JMAP API requests and responses, with optional support for push notifications. Furthermore, the WebSocket binding for JMAP can optionally compress [RFC7692] both JMAP API requests and responses. Although compression of HTTP responses is ubiquitous, compression of HTTP requests has very low, if any, deployment and therefore isn't a viable option for JMAP API requests over HTTP. 2. Conventions Used in This Document 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 document uses the terminology defined in the core JMAP specification [RFC8620]. 3. Discovering Support for JMAP over WebSocket The JMAP capabilities object is returned as part of the standard JMAP Session object (see Section 2 of [RFC8620]). Servers supporting this specification MUST add a property named "urn:ietf:params:jmap:websocket" to the capabilities object. The value of this property is an object that MUST contain the following information on server capabilities: * url: "String" The wss-URI (see Section 3 of [RFC6455]) to use for initiating a JMAP-over-WebSocket handshake (the "WebSocket URL endpoint" colloquially). * supportsPush: "Boolean" This is true if the server supports push notifications over the WebSocket, as described in Section 4.3.5. Example: "urn:ietf:params:jmap:websocket": { "url": "wss://server.example.com/jmap/ws/", "supportsPush": true } 4. JMAP Subprotocol The term WebSocket subprotocol refers to an application-levelShow full document text