handlebarsHelpers.js

const moment = require('moment');
const md = require('marked');

// Prevent markdown renderer wrapping all content in paragraphs
const renderer = new md.Renderer;
renderer.paragraph = function(text) {
  return text;
}

const dedupe = key => events => {
  const deduped = {};
  events && events.forEach(event => {
    event[key] && event[key].forEach(item => {
      deduped[item.name] = item;
    });
  });
  return Object.values(deduped);
}

module.exports = {
  'moment': function(date, format) {
    return new moment(date).format(format);
  },
  'withFirst': function(context, options) {
    return options.fn(context[0]);
  },
  'coalesce': function() {
    const len = arguments.length;
    for (let i = 0; i < len - 1; i ++) {
      if (arguments[i]) {
        return arguments[i];
      }
    }
    return;
  },
  'getLink': function(context, options) {
    const d = moment(context.date).format('YYYY-MM-DD');
    const title = (context.title || '').replace(/\W+/g, '-').replace(/-$/g, '');
    return `/${d}-${title}/`.toLowerCase();
  },
  'md': function(context, skipRenderer) {
    const options = skipRenderer ? undefined : { renderer: renderer };
    return context ? md(context, options) : context;
  },
  'lowerCase': function(context) {
    return context ? context.toLowerCase() : '';
  },
  'getSpeakers': dedupe('speakers'),
  'getSponsors': dedupe('sponsors'),
  'isEvent': function(context) {
    if (this.layout === 'event.html') {
      return context.fn(this);
    }
    return context.inverse(this);
  }
}