markdownを特定の文字数まで減らす

https://www.claritician.com/how-to-generate-an-excerpt-from-markdown-text
tunamaguro · May 5, 2023 · e843bc7 · e843bc7
1 parent 0b9f607
commit e843bc7
Show file tree

Hide file tree

Showing 3 changed files with 29 additions and 0 deletions.
diff --git a/app/package-lock.json b/app/package-lock.json
diff --git a/app/package.json b/app/package.json
@@ -29,13 +29,15 @@
     "react-dom": "^18.2.0",
     "rehype-katex": "^6.0.2",
     "remark-math": "^5.1.1",
+    "remove-markdown": "^0.5.0",
     "satori": "^0.7.3",
     "sharp": "^0.32.1",
     "tailwindcss": "^3.2.7",
     "twemoji-parser": "^14.0.0"
   },
   "devDependencies": {
     "@tailwindcss/typography": "^0.5.9",
+    "@types/remove-markdown": "^0.3.1",
     "@types/twemoji-parser": "^13.1.1",
     "prettier": "^2.8.4",
     "prettier-plugin-astro": "^0.8.0",

diff --git a/app/src/server/getMarkdownExcerpt/index.ts b/app/src/server/getMarkdownExcerpt/index.ts
@@ -0,0 +1,14 @@
+import removeMd from "remove-markdown";
+
+export function getMarkdownExcerpt(markdown: string, maxExcerptLength = 70) {
+  let parsedText = removeMd(markdown);
+  // 空白を正規化
+  const contentText = parsedText.trim().replace(/\s+/g, " ");
+  const excerpt = contentText.slice(0, maxExcerptLength);
+
+  if (contentText.length > maxExcerptLength) {
+    return excerpt + "...";
+  }
+
+  return excerpt;
+}