webthing-node-2

Node.js implementation of a W3C WoT web thing

This is a work-in-progress pure Node.js replacement for the webthing-node library which will implement the W3C WoT Thing Description and WoT Thing Protocol specifications.

Example Web Thing

To run an example web thing representing a lamp:

$ npm run example

Create Your Own Web Thing

Import the webthing library:

import { Thing, ThingServer } from 'webthing';

Create a partial Thing Description without Forms or security definitions:

const partialTD = {
  title: 'My Lamp',
  description: 'A web connected lamp',
  properties: {
    on: {
      type: 'boolean',
      title: 'On/Off',
      description: 'Whether the lamp is turned on',
    },
    level: {
      type: 'integer',
      title: 'Brightness',
      description: 'The level of light from 0-100',
      unit: 'percent',
      minimum: 0,
      maximum: 100,
    },
  },
  actions: {
    fade: {
      title: 'Fade',
      description: 'Fade the lamp to a given level',
      synchronous: false,
      input: {
        type: 'object',
        properties: {
          level: {
            title: 'Brightness',
            type: 'integer',
            minimum: 0,
            maximum: 100,
            unit: 'percent',
          },
          duration: {
            title: 'Duration',
            type: 'integer',
            minimum: 0,
            unit: 'milliseconds',
          },
        },
      },
    },
  },
  events: {
    overheated: {
      title: 'Overheated',
      data: {
        type: 'number',
        unit: 'degree celsius',
      },
      description: 'The lamp has exceeded its safe operating temperature',
    },
  },
};

Instantiate a Web Thing from the partial Thing Description:

const thing = new Thing(partialTD);

Set property handlers:

thing.setPropertyReadHandler('on', async function () {
  return true;
});

thing.setPropertyReadHandler('level', async function () {
  return 50;
});

Expose to the Thing to the Web of Things by starting its web server, providing a port number as an argument:

Create and start a Thing server using your Thing.

const server = new ThingServer(thing);

server.start(8080);

Development

Type Checking

You can type check this library against JSDoc annotations with:

$ npm run typecheck

Fixing Formatting

$ npm run format (to write the changes)

$ npm run format:check (just to run checks without writing)

Lint

Run the linter with:

$ npm run lint

Running Tests

You can run tests with:

$ npm test