Added code highlighting

server/utils/markdown.js

@@ -0,0 +1,45 @@
+import truncate from 'truncate-html';
+import marked, { Renderer } from 'marked';
+import highlight from 'highlight.js';
+
+const renderer = new Renderer();
+renderer.code = (code, language) => {
+  const validLang = !!(language && highlight.getLanguage(language));
+  const highlighted = validLang ? highlight.highlight(language, code).value : code;
+  return `<pre><code class="hljs ${language}">${highlighted}</code></pre>`;
+};
+
+
+marked.setOptions({
+  renderer: renderer,
+  gfm: true,
+  tables: true,
+  breaks: false,
+  pedantic: false,
+  sanitize: true,
+  smartLists: true,
+  smartypants: true,
+});
+
+// TODO: This is syncronous and can be costly,
+// should be performed outside http request
+const convertToMarkdown = (text) => {
+  return marked(text);
+};
+
+truncate.defaultOptions = {
+  stripTags: false,
+  ellipsis: '...',
+  decodeEntities: false,
+  excludes: ['h1', 'pre', ],
+};
+
+const truncateMarkdown = (text, length) => {
+  const html = convertToMarkdown(text);
+  return truncate(html, length);
+};
+
+export {
+  convertToMarkdown,
+  truncateMarkdown,
+};