khrome / character-scanner

Scan character buffers for patterns and generate events in javascript

character-scanner

character-scanner.js

This is a scanner for scanning streams of characters (like you get from keyboard or "wedge" devices). It's built to be a common basis for wedge drivers, but could also be used directly.

Usage

Character scanner supports buildless execution in all supported environments.

require the library

import { CharacterScanner } from 'character-scanner';
// OR: import { CharacterScanner } from 'character-scanner/src/index.ts';
// OR: const { CharacterScanner } = require('character-scanner');

the simplest way is to just use a function to determine what we're looking for:

const keyboardBuffer = new CharacterScanner();
keyboardBuffer.addScanner(function(bufferString){
    //return truthy value whether bufferString is selected
});

A more explicit way is to set it with options:

keyboardBuffer.addScanner({
    name: 'email',
    interval: 5000,
    scan: function(bufferString){
        //return truthy value whether bufferString is selected
    },
    callback: function(value){
        //do stuff
    }
});

And if you do provide a name you can then subscribe directly to events on the object instead of, or in addition to, the callback:

keyboardBuffer.on('email', function(value){
    //do stuff
})

Then you just wire the input stream to the scanner, by piping in characters:

keyboardBuffer.input(chars);

Testing

validate the typescript with

npm run ts

validate the module with

node ./src/index.mjs

validate the commonjs with

node ./src/index.cjs

Run the es module tests to test the typescript files

npm run ts-test

Run the es module tests to test the modules

npm run import-test

to run the same test inside the browser:

npm run browser-test

to run the same test headless in chrome:

npm run headless-browser-test

to run the same test inside docker:

npm run container-test

Run the commonjs tests against the /dist commonjs source (generated with the build-commonjs target).

npm run require-test

Development

All work is done in the .mjs files and will be transpiled on commit to commonjs and tested.

If the above tests pass, then attempt a commit which will generate .d.ts files alongside the src files and commonjs classes in dist