Ghost/core/server/helpers/reading_time.js
Rosco Kalis 301e1b2419 🎨Improved image counting for the {{reading_time}} helper (#9366)
refs #9200

- We have not yet counted the images within your html, this commit counts images based on the this algorithm: https://blog.medium.com/read-time-and-you-bc2048ab620c
- Added imageCount utility, which counts images using an img-tag regex, amended from the general tag-regex found in wordCount
- Added this imageCount to the {{reading_time}} helper, adding 12 seconds to the reading time for every image
- The feature image is still counted as before
- The first image adds 12 seconds, the second 11, the third 10, and so on
- Images from the tenth onwards add 3 seconds to the reading time
2018-03-05 09:30:15 +01:00

63 lines
2.1 KiB
JavaScript

// # Reading Time Helper
//
// Usage: `{{reading_time}}`
// or for translatable themes, with (t) translation helper's subexpressions:
// `{{reading_time seconds=(t "< 1 min read") minute=(t "1 min read") minutes=(t "% min read")}}`
// and in the theme translation file, for example Spanish es.json:
// "< 1 min read": "< 1 min de lectura",
// "1 min read": "1 min de lectura",
// "% min read": "% min de lectura",
//
// Returns estimated reading time for post
var proxy = require('./proxy'),
_ = require('lodash'),
schema = require('../data/schema').checks,
SafeString = proxy.SafeString,
localUtils = proxy.localUtils;
module.exports = function reading_time(options) {// eslint-disable-line camelcase
options = options || {};
options.hash = options.hash || {};
var html,
wordsPerMinute = 275,
wordsPerSecond = wordsPerMinute / 60,
wordCount,
imageCount,
readingTimeSeconds,
readingTimeMinutes,
readingTime,
seconds = _.isString(options.hash.seconds) ? options.hash.seconds : '< 1 min read',
minute = _.isString(options.hash.minute) ? options.hash.minute : '1 min read',
minutes = _.isString(options.hash.minutes) ? options.hash.minutes : '% min read';
// only calculate reading time for posts
if (!schema.isPost(this)) {
return null;
}
html = this.html;
imageCount = this.feature_image ? 1 : 0;
imageCount += localUtils.imageCount(html);
wordCount = localUtils.wordCount(html);
readingTimeSeconds = wordCount / wordsPerSecond;
for (var i = 12; i > 12 - imageCount; i -= 1) {
// add 12 seconds for the first image, 11 for the second, etc. limiting at 3
readingTimeSeconds += Math.max(i, 3);
}
readingTimeMinutes = Math.round(readingTimeSeconds / 60);
if (readingTimeSeconds < 60) {
readingTime = seconds;
} else if (readingTimeMinutes === 1) {
readingTime = minute;
} else {
readingTime = minutes.replace('%', readingTimeMinutes);
}
return new SafeString(readingTime);
};