CDDL

Concise data definition language (RFC 8610) implementation for JSON validator & code generator in Node.js

CDDL expresses Concise Binary Object Representation (CBOR) data structures (RFC 7049). Its main goal is to provide an easy and unambiguous way to express structures for protocol messages and data formats that use CBOR or JSON.

There are also CDDL parsers for other languages:

• Rust: anweiss/cddl

The package is currently mostly used to help generate typed interfaces for the WebDriver Bidi specification in the following projects:

• WebdriverIO - via the cddl2ts package and this script
• Selenium - via the cddl2java package

Note: this is work in progress, feel free to have a look at the code or contribute but don't use this for anything yet!

Install

To install one of the packages run:

# Parser & validator
$ npm install @wdio/cddl

# Generate typescript definition
$ npm install @wdio/cddl2ts

Using packages

The packages expose a CLI as well as a programmatic interface for parsing and transforming CDDL.

CLI

The cddl CLI offers a validate command that helps identify invalid CDDL formats, e.g.:

npx @wdio/cddl validate ./path/to/interface.cddl
✅ Valid CDDL file!

The cddl2ts CLI allows transforming CDDL into TypeScript:

npx @wdio/cddl2ts ./path/to/interface.cddl &> ./path/to/interface.ts

Programmatic Interface

You can import any of the packages into your typescript project for an easy integration

• cddl example
• cddl2ts example

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If you are interested in this project, please feel free to contribute ideas or code patches. Have a look at our contributing guidelines to get started.