hexo-generator-readtime/index.js

HEXO package that provides analytics on the read time to review a post. Generates word, character, image, video, and codeblock counts in the front-matter of the markdown file. Plus provides read-time estimates for given language profile. Supports 48 langu

/* eslint-env es6 */
'use strict';

var hexo = hexo || {};
var front = require('hexo-front-matter');
var fs = require('hexo-fs');
var readTime = require('./lib/readTime');
// const rtSettings = JSON.parse(
//   await fs.readFile(new URL('./Settings/_readTime.json', import.meta.url))
// );

const rtSettings = require('./Settings/_readTime.json');

// debugger; //tell vscode to stop here for debugging


/**
 * @function readTime_init
 * @description initializes parameters and logic for readTime plugin
 * @param {object} post hexo object
 * @return {object} post updated with readTime metrics
 */
let readTime_init = function (post) {

    // only update articles in the `_posts` folder
    if (post.layout != 'post')
        return post;
    if (!this.config.render_drafts && post.source.startsWith("_drafts/"))
        return post;

    //Debug output status when enabled by `--debug` flag
    hexo.log.debug(`ReadTime scanning:  ${post.source}`);

    // check language defaults
    let lang = post.lang || hexo.config.language[0] || 'en'; //ISO-639-1 code

    // use `_config.yml` readTime setting if defined. Otherwise, plugin defaults.
    if (typeof hexo.config.readTime == "object") {

        Object.assign(rtSettings, hexo.config.readTime);

    }

    // override option defaults if provided
    let rtConfig = {
        defaultTime: rtSettings.defaultTime,
        imgReadTime: rtSettings.imgReadTime,
        vidReadTime: rtSettings.vidReadTime
    };

    // confirm detected lang code exist in settings
    if (!rtSettings.langProfile.hasOwnProperty(lang)){
        hexo.log.i("Language Profile \"%s\" not found for [%s]. Defaulting to English.", lang, post.title);

        //language profile not found. Default back to English
        lang = "en";
    }

    let rtObj = new readTime(rtSettings.langProfile[lang], post.content, rtConfig);
    let rtString = rtObj.calculate();

    let rtMetrics = {
        wordCount: rtObj.wordCount,
        charCount: rtObj.charCount,
        imgCount: rtObj.imgCount,
        vidCount: rtObj.vidCount,
        wsCount: rtObj.wsCount,
        cbCount: rtObj.codeBlockCount,
        readTime: rtString
    };

    Object.assign(post, rtMetrics); //merge metrics with post data

    // parse front matter
    let tmpPost = front.parse(post.raw);

    // only update if value is different
    if (tmpPost.readTime != rtString || tmpPost.charCount != rtObj.charCount) {

        // Update front-matter
        Object.assign(tmpPost, rtMetrics); //merge new front-matter data

        // only update if time is greater than 0 and `hexo generate`
        if (rtObj.time > 0 && hexo._isGenerating) {

            // overwrite markdown file
            fs.writeFile(post.full_source, '---\n' + front.stringify(tmpPost), 'utf-8');

            //show debug info
            hexo.log.info("Generated: readTime [%s] %j", post.source, rtMetrics);
        }
    }

    //update in-memory data
    return post;
};


/*
 * Register the `before_post_render` event listener to trigger readTime
 * See https://hexo.io/api/events for further details on events
 */
hexo.extend.filter.register('before_post_render', readTime_init, 15 );