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watcher.js

'use strict';

/*
*   Run the Metalsmith build upon hbs and json changes
*   This enables live reloading of template and data changes
*/

const { watch } = require('fs');
const { spawn: run } = require('child_process');
const { resolve, extname } = require('path');
const src = resolve(__dirname, '../src/app');

watch(src, {recursive: true}, (eventType, file) => {
    let extension = extname(file);

    if (extension === '.hbs' || extension === '.json') {
        run('npm', ['run', 'metalsmith'], {stdio: 'inherit'});
    }

});