cogear/lib/plugins/preload.js

Cogear.JS – modern static websites generator (Node.JS/Webpack)

const path = require('path');
const glob = require('glob');
const fs = require('fs');
const chalk = require('chalk');
const now = require('performance-now');
const prettyMs = require('pretty-ms');
const yamlFront = require('yaml-front-matter');
cogear.parser = require('../utils/parser')();
const {forEach} = require('p-iteration');
const merge = require('webpack-merge');

module.exports = {
  apply(){
    cogear.on('preload',async()=>{
      await this.preload();
    });
    cogear.on('preload.page',async ([file,obj])=>{
      let page =  await this.page(file,obj);
      return page;
    });
  },
  async preload(){
    if(!cogear.webpackConfig){
      cogear.loader.fail('Webpack config must be loaded before pages preload starts.');
      process.exit();
    }
    return new Promise(async(resolve)=>{
      cogear.loader.start('Preloading pages...\n');
      let files = glob.sync(`**/*.@(${cogear.pageFormats.join('|')})`, { cwd: cogear.options.srcPages });
      cogear.pages = {};
      let start = now();
      if (!files.length) {
        cogear.loader.fail(`No files are found in the source dir ${chalk.bold(cogear.options.src.replace(require('os').homedir,'~'))}.\nPlease, make sure that at least one page file is available.`);
        process.exit();
      }	
      await cogear.emit('preload.before');
      await forEach(files, async (file) => {
        await cogear.emit('preload.page',[file]);
      });
      cogear.loader.succeed(`${chalk.whiteBright.bold('Preloaded')} in ${prettyMs(now()-start)}.`);	
      await cogear.emit('preload.done');
      resolve();	
    });
  },
  async page(file,page){
    return new Promise(async(resolve,reject)=>{
      // 1. If file but no page object
      if(file){
        page = {
          file: file,
          filePath: path.join(cogear.options.srcPages,file),
        };
        try {
          page = merge(page,yamlFront.loadFront(fs.readFileSync(page.filePath, 'utf-8')));
        } catch (e){
          console.error(e.message);
        }
        let stats = fs.statSync(page.filePath);
        page.date = page.date || new Date(stats.birthtimeMs);
        page.created_at = page.date;
        page.updated_at = stats.mtime;
      } 
      page.filename = path.parse(page.file).name,
      page.format = path.extname(page.file);						
      // 4. Set page path (in output folder) and uri (in browser)
      if (page.uri) {
        page.path = page.uri.indexOf('.html') != -1 ? page.uri : page.uri + '/index.html';
      } else {
        page.path = page.file.replace(/\.(md|html|pug|ejs|hbs)$/, '') + (page.filename == 'index' ? '.html' : '/index.html');
        page.uri = page.path.replace('index.html','');
      }
      // 5. Merge with global config page-per-uri-regex params
      /**
			 * You can set pages params for any match path globally in ./config.yaml
			 * 
			 * pages:
			 * 	docs/: # Any page uri that matched to given page. Can be regexp
			 * 		layout: docs # Any params from YAML-front-matter
			 * 		js:
			 *		 		- js/docs.js # Path relative to ./src dir
			 */
      if(cogear.config.pages){
        Object.keys(cogear.config.pages)
          .filter(regex=>{ // If match page path
            return new RegExp(regex).test(page.uri);
          }) 
          .forEach(key=>{ // Copy given options to the page
            page = merge(page,cogear.config.pages[key]);
          });
      }
      // 6. Render page
      await cogear.emit('preload.page.parse',page);
      if(page.__content){
        try {
          page.content  = await cogear.parser.render(page.__content, page);
        } catch (e){
          console.error(`\n ${chalk.red(e)} \n`);
          reject(e);
        }
      }
      await cogear.emit('preload.page.parse.after',page);
      // 7. Processing js entry points (chunks)
      page.chunks = ['app']; 
			
      await cogear.emit('preload.page.chunks',page);
      // Inject js
      if(Array.isArray(page.js)){
        page.chunks = [];
        // Avoid duplicates
        page.js = page.js.filter((v, i, a) => a.indexOf(v) === i);
        // if(!page.keepJS) page.chunks = []
        for(let script of page.js){
          let scriptPath = script.indexOf(cogear.baseDir) !== -1 ? script : path.join(cogear.options.src,script);
          if(script.indexOf(cogear.baseDir) !== -1){
            script = script.replace(process.cwd()+'/','');
          }
          if(cogear.mode == 'development'){
            cogear.webpackConfig.entry[script] = [path.join(cogear.baseDir,'lib','hot.js'),scriptPath];
          } else {
            cogear.webpackConfig.entry[script] = [scriptPath];
          }
          page.chunks.push(script);				
        }
      }
      await cogear.emit('preload.page.chunks.after',page);
      // 8. Add to global pages array
      cogear.pages[page.uri] = page;
      resolve(page);
    });
  }
};