fix(blog): ensure unique and valid slugs for tag pages

- fix: improve slugifyTag to support non-ASCII characters (Japanese/etc)
- fix: filter empty slugs in getStaticPaths to prevent build errors
- fix: eliminate duplicate slugs in tag page generation

Author: leonism

CHANGELOG

@@ -19,6 +19,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - **fix(search):** Removed unused test file `EnhancedSearchEngine.test.ts`.
 - **fix(blog):** Corrected the blog tags link generation to point to the new static tag pages instead of using query parameters, ensuring distinct URLs for each tag view.
 - **fix(api):** Updated the `/api/get-posts` endpoint to return server-rendered HTML fragments (using `BlogCard`) instead of JSON, aligning with the client-side consumption model.
+- **fix(blog):** Resolved "Missing parameter: tag" build error by enhancing `slugifyTag` to support non-ASCII characters and filtering out empty slugs in `getStaticPaths`.
 ## [1.0.6] - 2026-01-10
 
 ### Changed

src/i18n/utils.ts

@@ -87,9 +87,10 @@ export function isValidLanguage(lang: string): lang is keyof typeof ui {
 export function slugifyTag(tag: string) {
   return tag
     .toLowerCase()
+    .trim()
     .replace(/\s+/g, '-')
     .replace(/\//g, '-')
-    .replace(/[^\w-]+/g, '')
+    .replace(/[!"#$%&'()*+,.:;<=>?@\[\\\]^`{|}~]/g, '') // Remove common symbols except hyphen
     .replace(/--+/g, '-')
     .replace(/^-+/, '')
     .replace(/-+$/, '');

src/pages/[lang]/blog/tags/[tag].astro

@@ -8,18 +8,22 @@ import { ui } from '@/i18n/ui';
 export async function getStaticPaths() {
   const allPosts = await getCollection('blog');
   const uniqueTags = [...new Set(allPosts.flatMap(post => post.data.tags || []))];
-  const validTags = uniqueTags.filter(tag => tag && tag.trim().length > 0);
   const languages = ['es', 'ja']; // en is handled separately
 
-  return languages.flatMap(lang =>
-    validTags.map(tag => ({
-      params: {
-        lang,
-        tag: slugifyTag(tag)
-      },
-      props: { tag }
-    }))
-  );
+  return languages.flatMap(lang => {
+    const paths = uniqueTags
+      .map(tag => {
+        const slug = slugifyTag(tag);
+        return {
+          params: { lang, tag: slug },
+          props: { tag }
+        };
+      })
+      .filter(path => path.params.tag.length > 0);
+
+    // Eliminate duplicate slugs per language
+    return Array.from(new Map(paths.map(p => [p.params.tag, p])).values());
+  });
 }
 
 const { tag } = Astro.props;

src/pages/en/blog/tags/[tag].astro

@@ -7,12 +7,21 @@ import { useTranslations, slugifyTag } from '@/i18n/utils';
 export async function getStaticPaths() {
   const allPosts = await getCollection('blog');
   const uniqueTags = [...new Set(allPosts.flatMap(post => post.data.tags || []))];
-  const validTags = uniqueTags.filter(tag => tag && tag.trim().length > 0);
 
-  return validTags.map(tag => ({
-    params: { tag: slugifyTag(tag) },
-    props: { tag }
-  }));
+  const paths = uniqueTags
+    .map(tag => {
+      const slug = slugifyTag(tag);
+      return {
+        params: { tag: slug },
+        props: { tag }
+      };
+    })
+    .filter(path => path.params.tag.length > 0);
+
+  // Eliminate duplicate slugs
+  const uniquePaths = Array.from(new Map(paths.map(p => [p.params.tag, p])).values());
+
+  return uniquePaths;
 }
 
 const { tag } = Astro.props;