feat: add highlight for article html.

src/articles/articles.resolver.ts

@@ -12,6 +12,7 @@ import { Article } from './entities/article.entity';
 import { CreateArticleInput } from './dto/create-article.input';
 import { UpdateArticleInput } from './dto/update-article.input';
 import * as marked from 'marked';
+import { getLanguage, highlight } from 'highlight.js';
 
 @Resolver(() => Article)
 export class ArticlesResolver {
@@ -49,7 +50,22 @@ export class ArticlesResolver {
 
   @ResolveField(() => String)
   async html(@Parent() article: Article) {
-    return marked(article.content);
+    const tokens = marked.lexer(article.content);
+    const index = tokens.findIndex((token) => ['heading'].includes(token.type));
+    if (index !== -1) {
+      tokens.splice(index, 1);
+    }
+    return marked.parser(tokens, {
+      gfm: true,
+      smartLists: true,
+      smartypants: true,
+      langPrefix: 'hljs language-',
+      highlight: (code, language) => {
+        return highlight(code, {
+          language: getLanguage(language) ? language : 'plaintext',
+        }).value;
+      },
+    });
   }
 
   @ResolveField(() => String, { nullable: true })