The Constrained RESTful Application Language (CoRAL)

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Last updated 2020-03-09
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CoRE Working Group                                             K. Hartke
Internet-Draft                                                  Ericsson
Intended status: Standards Track                            9 March 2020
Expires: 10 September 2020

          The Constrained RESTful Application Language (CoRAL)


   The Constrained RESTful Application Language (CoRAL) defines a data
   model and interaction model as well as two specialized serialization
   formats for the description of typed connections between resources on
   the Web ("links"), possible operations on such resources ("forms"),
   and simple resource metadata.

Note to Readers

   This note is to be removed before publishing as an RFC.

   The issues list for this Internet-Draft can be found at

   Companion material for this Internet-Draft can be found at

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Table of Contents

   1.  Introduction
     1.1.  Data and Interaction Model
     1.2.  Serialization Formats
     1.3.  Notational Conventions
   2.  Data and Interaction Model
     2.1.  Browsing Context
     2.2.  Documents
     2.3.  Links
     2.4.  Forms
     2.5.  Form Fields
     2.6.  Navigation
     2.7.  History Traversal
   3.  Binary Format
     3.1.  Data Structure
       3.1.1.  Documents
       3.1.2.  Directives
       3.1.3.  IRIs
       3.1.4.  Links
       3.1.5.  Forms
       3.1.6.  Form Fields
     3.2.  Dictionary Compression
       3.2.1.  Dictionary References
       3.2.2.  Media Type Parameter
     3.3.  Export Interface
   4.  Textual Format
     4.1.  Lexical Structure
       4.1.1.  Line Terminators
       4.1.2.  White Space
       4.1.4.  Identifiers
       4.1.5.  Literals
       4.1.6.  Punctuators
     4.2.  Syntactic Structure
       4.2.1.  Documents
       4.2.2.  Directives
       4.2.3.  IRIs
       4.2.4.  Links
       4.2.5.  Forms
       4.2.6.  Form Fields
   5.  Document Semantics
     5.1.  Submitting Documents
       5.1.1.  PUT Requests
       5.1.2.  POST Requests
     5.2.  Returning Documents
       5.2.1.  Success Responses
       5.2.2.  Redirection Responses
       5.2.3.  Error Responses
   6.  Usage Considerations
     6.1.  Specifying CoRAL-based Applications
       6.1.1.  Application Interfaces
       6.1.2.  Resource Identifiers
       6.1.3.  Implementation Limits
     6.2.  Minting Vocabulary
     6.3.  Expressing Registered Link Relation Types
     6.4.  Expressing Simple RDF Statements
     6.5.  Expressing Natural Language Texts
     6.6.  Embedding Representations in CoRAL
   7.  Security Considerations
   8.  IANA Considerations
     8.1.  Media Type "application/coral+cbor"
     8.2.  Media Type "text/coral"
     8.3.  CoAP Content Formats
     8.4.  CBOR Tag
   9.  References
     9.1.  Normative References
     9.2.  Informative References
   Appendix A.  Core Vocabulary
     A.1.  Base
     A.2.  Collections
     A.3.  HTTP
     A.4.  CoAP
   Appendix B.  Default Dictionary
   Appendix C.  Change Log
   Author's Address

1.  Introduction

   The Constrained RESTful Application Language (CoRAL) is a language
   for the description of typed connections between resources on the Web
   ("links"), possible operations on such resources ("forms"), and
   simple resource metadata.

   CoRAL is intended for driving automated software agents that navigate
   a Web application based on a standardized vocabulary of link relation
   types and operation types.  It is designed to be used in conjunction
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