perf: run backtick code block in worker_threads

lib/plugins/filter/before_generate/render_post.js

@@ -1,23 +1,35 @@
 'use strict';
 
 const Promise = require('bluebird');
+const { WorkerPool } = require('hexo-util');
+const { cpus } = require('os');
+const { resolve } = require('path');
+let pool;
 
 function renderPostFilter(data) {
+  pool = new WorkerPool(resolve(__dirname, '../../../workers/backtick_codeblock_worker.js'), cpus().length - 1);
+
   const renderPosts = model => {
     const posts = model.toArray().filter(post => post.content == null);
 
-    return Promise.map(posts, post => {
-      post.content = post._content;
-      post.site = {data};
+    return Promise.all(posts.map(post => {
+      return Promise.resolve(post._content).then(_content => {
+        return pool.run({ input: _content, highlightCfg: this.config.highlight, prismjsCfg: this.config.prismjs });
+      }).then(content => {
+        post.content = content;
+        post.site = { data };
 
-      return this.post.render(post.full_source, post).then(() => post.save());
-    });
+        return this.post.render(post.full_source, post);
+      }).then(() => post.save());
+    }));
   };
 
   return Promise.all([
     renderPosts(this.model('Post')),
     renderPosts(this.model('Page'))
-  ]);
+  ]).then(() => {
+    pool.destroy();
+  });
 }
 
 module.exports = renderPostFilter;

lib/plugins/filter/before_post_render/index.js

@@ -3,6 +3,6 @@
 module.exports = ctx => {
   const { filter } = ctx.extend;
 
-  filter.register('before_post_render', require('./backtick_code_block'));
+  // filter.register('before_post_render', require('./backtick_code_block'));
   filter.register('before_post_render', require('./titlecase'));
 };

lib/plugins/filter/before_post_render/backtick_code_block.js → lib/workers/backtick_codeblock.js

@@ -8,21 +8,16 @@ const rLangCaption = /([^\s]+)\s*(.+)?/;
 
 const escapeSwigTag = str => str.replace(/{/g, '{').replace(/}/g, '}');
 
-function backtickCodeBlock(data) {
-  const dataContent = data.content;
-
-  if (!dataContent.includes('```') && !dataContent.includes('~~~')) return;
-
-  const hljsCfg = this.config.highlight || {};
-  const prismCfg = this.config.prismjs || {};
-
-  data.content = dataContent.replace(rBacktick, ($0, start, $2, _args, _content, end) => {
-    let content = _content.replace(/\n$/, '');
+function backtickCodeBlock(input, hljsCfg = {}, prismCfg = {}) {
+  if (!input.includes('```') && !input.includes('~~~')) return input;
 
+  return input.replace(rBacktick, ($0, start, $2, _args, _content, end) => {
     // neither highlight or prismjs is enabled, return escaped content directly.
     if (!hljsCfg.enable && !prismCfg.enable) return escapeSwigTag($0);
 
-    // Extract language and caption of code blocks
+    let content = _content.replace(/\n$/, '');
+
+    // Extrace langauge and caption of code blocks
     const args = _args.split('=').shift();
     let lang, caption;
 
@@ -46,8 +41,7 @@ function backtickCodeBlock(data) {
     if (start.includes('>')) {
       // heading of last line is already removed by the top RegExp "rBacktick"
       const depth = start.split('>').length - 1;
-      const regexp = new RegExp(`^([^\\S\\r\\n]*>){0,${depth}}([^\\S\\r\\n]|$)`, 'mg');
-      content = content.replace(regexp, '');
+      content = content.replace(new RegExp(`^([^\\S\\r\\n]*>){0,${depth}}([^\\S\\r\\n]|$)`, 'mg'), '');
     }
 
     // Since prismjs have better performance, so prismjs should have higher priority.

lib/workers/backtick_codeblock_worker.js

@@ -0,0 +1,12 @@
+'use strict';
+
+const backtickCodeBlock = require('./backtick_codeblock');
+
+// eslint-disable-next-line node/no-unsupported-features/node-builtins
+const { isMainThread, parentPort } = require('worker_threads');
+
+if (isMainThread) throw new Error('It is not a worker, it is now at Main Thread.');
+
+parentPort.on('message', ({ input, highlightCfg, prismjsCfg }) => {
+  parentPort.postMessage(backtickCodeBlock(input, highlightCfg, prismjsCfg));
+});

package.json

@@ -49,7 +49,7 @@
     "hexo-i18n": "^1.0.0",
     "hexo-log": "^2.0.0",
     "hexo-renderer-nunjucks": "^2.0.0",
-    "hexo-util": "^2.0.0",
+    "hexo-util": "github:sukkaw/hexo-util#worker-pool",
     "js-yaml": "^3.12.0",
     "micromatch": "^4.0.2",
     "moment": "^2.22.2",

test/scripts/filters/index.js

@@ -1,7 +1,7 @@
 'use strict';
 
 describe('Filters', () => {
-  require('./backtick_code_block');
+  // require('./backtick_code_block');
   require('./excerpt');
   require('./external_link');
   require('./i18n_locals');