RSS 피드 썸네일 정보 추가

server/utils/rss-feed.js

@@ -22,6 +22,34 @@ const escapeXml = (value) => String(value || '')
  */
 const normalizeSiteUrl = (value) => String(value || '').trim().replace(/\/+$/, '')
 
+/**
+ * URL을 절대 URL로 변환한다.
+ * @param {unknown} value - 원본 URL
+ * @param {string} siteUrl - 사이트 URL
+ * @returns {string} 절대 URL
+ */
+const toAbsoluteUrl = (value, siteUrl) => {
+  const url = String(value || '').trim()
+
+  if (!url) {
+    return ''
+  }
+
+  if (/^https?:\/\//i.test(url)) {
+    return url
+  }
+
+  if (url.startsWith('//')) {
+    return `https:${url}`
+  }
+
+  if (url.startsWith('/')) {
+    return `${siteUrl}${url}`
+  }
+
+  return `${siteUrl}/${url.replace(/^\/+/, '')}`
+}
+
 /**
  * RSS 날짜 문자열을 만든다.
  * @param {unknown} value - ISO 날짜 문자열
@@ -45,6 +73,14 @@ const formatRssDate = (value) => {
  */
 const getPostUrl = (post, siteUrl) => `${siteUrl}/post/${encodeURIComponent(post.slug)}`
 
+/**
+ * 게시물 RSS 썸네일 URL을 반환한다.
+ * @param {Object} post - 게시물
+ * @param {string} siteUrl - 사이트 URL
+ * @returns {string} 썸네일 절대 URL
+ */
+const getPostThumbnailUrl = (post, siteUrl) => toAbsoluteUrl(post.ogImage || post.featuredImage, siteUrl)
+
 /**
  * RSS item XML을 만든다.
  * @param {Object} post - 게시물
@@ -53,6 +89,7 @@ const getPostUrl = (post, siteUrl) => `${siteUrl}/post/${encodeURIComponent(post
  */
 const buildRssItem = (post, siteUrl) => {
   const postUrl = getPostUrl(post, siteUrl)
+  const thumbnailUrl = getPostThumbnailUrl(post, siteUrl)
   const description = createPostSummary(post.excerpt, post.content, {
     maxLength: 280,
     appendEllipsis: true
@@ -65,6 +102,8 @@ const buildRssItem = (post, siteUrl) => {
     `      <link>${escapeXml(postUrl)}</link>`,
     `      <guid isPermaLink="true">${escapeXml(postUrl)}</guid>`,
     `      <pubDate>${escapeXml(formatRssDate(publishedAt))}</pubDate>`,
+    thumbnailUrl ? `      <media:thumbnail url="${escapeXml(thumbnailUrl)}" />` : '',
+    thumbnailUrl ? `      <media:content url="${escapeXml(thumbnailUrl)}" medium="image" />` : '',
     description ? `      <description>${escapeXml(description)}</description>` : '',
     '    </item>'
   ].filter(Boolean).join('\n')
@@ -89,7 +128,7 @@ export const buildRssFeed = async (selfPath = '/rss.xml', fallbackSiteUrl = '')
 
   return [
     '<?xml version="1.0" encoding="UTF-8"?>',
-    '<rss version="2.0" xmlns:atom="http://www.w3.org/2005/Atom">',
+    '<rss version="2.0" xmlns:atom="http://www.w3.org/2005/Atom" xmlns:media="http://search.yahoo.com/mrss/">',
     '  <channel>',
     `    <title>${escapeXml(settings.title)}</title>`,
     `    <link>${escapeXml(siteUrl)}</link>`,