refactor note processing functions

lib/helpers/posts.ts

@@ -19,46 +19,8 @@ export type FrontMatter = {
   noComments?: boolean;
 };
 
-// returns front matter and the **raw & uncompiled** markdown of a given slug
-export const getFrontMatter = cache(async (slug: string): Promise<FrontMatter | undefined> => {
-  try {
-    const { frontmatter } = await import(`../../${POSTS_DIR}/${slug}/index.mdx`);
-
-    // process markdown title to html...
-    const htmlTitle = await unified()
-      .use(remarkParse)
-      .use(remarkSmartypants)
-      .use(remarkHtml, {
-        sanitize: {
-          // allow *very* limited markdown to be used in post titles
-          tagNames: ["code", "em", "strong"],
-        },
-      })
-      .process(frontmatter.title)
-      .then((result) => result.toString().trim());
-
-    // ...and then (sketchily) remove said html for a plaintext version:
-    // https://css-tricks.com/snippets/javascript/strip-html-tags-in-javascript/
-    const title = decode(htmlTitle.replace(/<[^>]*>/g, ""));
-
-    return {
-      ...(frontmatter as Partial<FrontMatter>),
-      // plain title without html or markdown syntax:
-      title,
-      // stylized title with limited html tags:
-      htmlTitle,
-      slug,
-      date: new Date(frontmatter.date).toISOString(), // validate/normalize the date string provided from front matter
-      permalink: `${BASE_URL}/${POSTS_DIR}/${slug}`,
-    };
-  } catch (error) {
-    console.error(`Failed to load front matter for post with slug "${slug}":`, error);
-    return undefined;
-  }
-});
-
-// use filesystem to get a simple list of all post slugs
-export const getPostSlugs = cache(async (): Promise<string[]> => {
+/** Use filesystem to get a simple list of all post slugs */
+export const getSlugs = cache(async (): Promise<string[]> => {
   // list all .mdx files in POSTS_DIR
   const mdxFiles = await glob("*/index.mdx", {
     cwd: path.join(process.cwd(), POSTS_DIR),
@@ -71,10 +33,76 @@ export const getPostSlugs = cache(async (): Promise<string[]> => {
   return slugs;
 });
 
-// returns the content of a post with very limited processing to include in RSS feeds
-// TODO: also remove MDX-related syntax (e.g. import/export statements)
-export const getPostContent = cache(async (slug: string): Promise<string | undefined> => {
+// overloaded to return either the front matter of a single post or ALL posts
+export const getFrontMatter: {
+  /**
+   * Parses and returns the front matter of ALL posts, sorted reverse chronologically
+   */
+  (): Promise<FrontMatter[]>;
+  /**
+   * Parses and returns the front matter of a given slug, or undefined if the slug does not exist
+   */
+  (slug: string): Promise<FrontMatter | undefined>;
+} = cache(
+  // eslint-disable-next-line @typescript-eslint/no-explicit-any
+  async (slug?: any): Promise<any> => {
+    if (typeof slug === "string") {
+      try {
+        const { frontmatter } = await import(`../../${POSTS_DIR}/${slug}/index.mdx`);
+
+        // process markdown title to html...
+        const htmlTitle = await unified()
+          .use(remarkParse)
+          .use(remarkSmartypants)
+          .use(remarkHtml, {
+            sanitize: {
+              // allow *very* limited markdown to be used in post titles
+              tagNames: ["code", "em", "strong"],
+            },
+          })
+          .process(frontmatter.title)
+          .then((result) => result.toString().trim());
+
+        // ...and then (sketchily) remove said html for a plaintext version:
+        // https://css-tricks.com/snippets/javascript/strip-html-tags-in-javascript/
+        const title = decode(htmlTitle.replace(/<[^>]*>/g, ""));
+
+        return {
+          ...(frontmatter as Partial<FrontMatter>),
+          // plain title without html or markdown syntax:
+          title,
+          // stylized title with limited html tags:
+          htmlTitle,
+          slug,
+          // validate/normalize the date string provided from front matter
+          date: new Date(frontmatter.date).toISOString(),
+          permalink: `${BASE_URL}/${POSTS_DIR}/${slug}`,
+        } as FrontMatter;
+      } catch (error) {
+        console.error(`Failed to load front matter for post with slug "${slug}":`, error);
+        return undefined;
+      }
+    }
+
+    if (!slug) {
+      // concurrently fetch the front matter of each post
+      const slugs = await getSlugs();
+      const posts = await Promise.all(slugs.map(getFrontMatter));
+
+      // sort the results reverse chronologically and return
+      return posts.sort(
+        (post1, post2) => new Date(post2!.date).getTime() - new Date(post1!.date).getTime()
+      ) as FrontMatter[];
+    }
+
+    throw new Error(`getFrontMatter() called with invalid argument.`);
+  }
+);
+
+/** Returns the content of a post with very limited processing to include in RSS feeds */
+export const getContent = cache(async (slug: string): Promise<string | undefined> => {
   try {
+    // TODO: also remove MDX-related syntax (e.g. import/export statements)
     const content = await unified()
       .use(remarkParse)
       .use(remarkFrontmatter)
@@ -104,20 +132,10 @@ export const getPostContent = cache(async (slug: string): Promise<string | undef
       })
       .process(await read(path.resolve(process.cwd(), `${POSTS_DIR}/${slug}/index.mdx`)));
 
-    // convert the parsed content to a string
-    return content.toString().trim();
+    // convert the parsed content to a string with "safe" HTML
+    return content.toString().replaceAll("<p></p>", "").trim();
   } catch (error) {
     console.error(`Failed to load/parse content for post with slug "${slug}":`, error);
     return undefined;
   }
 });
-
-// returns the parsed front matter of ALL posts, sorted reverse chronologically
-export const getAllPosts = cache(async (): Promise<FrontMatter[]> => {
-  // concurrently fetch the front matter of each post
-  const slugs = await getPostSlugs();
-  const posts = (await Promise.all(slugs.map(getFrontMatter))) as FrontMatter[];
-
-  // sort the results reverse chronologically and return
-  return posts.sort((post1, post2) => new Date(post1.date).getTime() - new Date(post2.date).getTime());
-});