blog.hangerthem.com/app/posts/[slug]/page.tsx
HangerThem 30ef0d611e Bug fixes, SEO, performance and accessibility pass (#1)
## Summary

A cleanup pass across the blog: route and feed bugs fixed, SEO basics added, smaller and lazier images, accessibility fixes, and a real README. No content or design changes beyond small fixes.

## Bug fixes

- **Tag/category pages**: static params now use slugs, so pre-rendered pages match the links (before, `/tags/standard-model` was only rendered on demand and the pre-built pages said "Tag not found"). Unknown slugs now return a real 404, and there's a new not-found page.
- **Recently updated**: sorts by last modification *before* taking the top 5, so older posts that were updated recently now show up.
- **Atom feed**: `rel="self"` now points to `/feed.xml` (was `/feed`); `<updated>` uses the `updated` frontmatter field.
- **No-JS flash**: the `no-js` → `js` class swap runs in an inline `<head>` script before first paint, not after hydration.
- **Markdown links**: only internal paths go through `next/link`; `#anchors`, `mailto:` and links without an `href` no longer break.
- **Invalid HTML**: images in a paragraph together with text (e.g. "**Screenshots:**" followed by images on the Projects page) produced `<p><figure>` and a hydration error. Those paragraphs are now split.
- **Dates**: frontmatter dates are normalized to ISO, so `<time datetime>` values are valid. Formatting is pinned to Europe/Prague so a UTC build server can't shift a date by a day.

## SEO

- `sitemap.xml` and `robots.txt`
- Canonical URLs, Twitter cards and a feed link on every page, built by a shared `pageMetadata()` helper
- Generated Open Graph images: a site card, and for each post its cover image or a branded title card (pre-rendered at build time)
- `BlogPosting` JSON-LD on post pages

## Performance

- Only the post cover and the latest-post image are preloaded (was: every image)
- In-post image quality 100 → 90, plus responsive `sizes`
- Screenshots downscaled to 1800px wide; `linkboard-old.png` converted to WebP (3.1 MB → 60 KB)
- `CodeWrapper` is now a server component; only the copy button ships to the client
- Mermaid CDN script pinned to `11.17.2` for reproducible builds

## Accessibility

- Accessible names for icon-only links (share, social, mobile nav) and `aria-current` on active nav items
- Copy button: uses React state instead of mutating `innerHTML`, handles clipboard errors, announces the result to screen readers, and is no longer inside an `aria-hidden` header
- Code-block line numbers hidden from screen readers
- Image captions: the Markdown `"title"` becomes the caption; captions that only repeat the alt text are hidden from screen readers

## Content & maintenance

- **Frontmatter validation**: a missing or malformed field fails the build and names the file, instead of rendering a broken post
- **`draft: true` support**: drafts only render in development
- About/Projects/Setup pages share one `MarkdownPage` component; tag/category lists share `PostList`
- Markdown rendering is cached, so metadata and page share one render
- New README covering features, env vars, frontmatter schema, Markdown extensions and deployment
- Removed unused ESLint setup and the unrelated `hast` package; `oxlint`, `oxfmt` and `puppeteer` moved to devDependencies (locked versions unchanged)
- Typo fix in the Tessera cover alt text; removed unused `math`/`mermaid` flags from two posts

## Deployment notes

- **`SITE_URL` is now required**: the build fails with a clear error if it's missing.
- **Puppeteer is a devDependency now**: Nixpacks installs dev dependencies for the build by default, but check that Mermaid diagrams render on the first deploy (the Standard Model post has one).

## Testing

- `tsc --noEmit` and `bun run lint` pass
- `bun run build` passes; all 81 pages are generated statically
- Smoke-tested `next start`: posts, tags, categories, feed, sitemap and OG images return 200; unknown tags and routes return 404
- No block elements nested inside `<p>` in any built page

Reviewed-on: #1
2026-10-19 12:41:40 +00:00

194 lines
7.2 KiB
TypeScript

import { AUTHOR, pageMetadata, SITE_NAME, SITE_URL } from '@/app/metadata'
import { ImageWrapper } from '@/components/content/ImageWrapper'
import { ShareLinks } from '@/components/post/ShareLinks'
import { TableOfContents } from '@/components/post/TableOfContents'
import { getAllPostSlugs, getNextAndPreviousPosts, getPostBySlug } from '@/lib/posts'
import { slugify } from '@/utils/slug'
import { dateTimeFormatter, shortDateFormatter } from '@/utils/time'
import { ArrowLeft, ArrowRight, Pencil, SendHorizonal } from 'lucide-react'
import type { Metadata } from 'next'
import Link from 'next/link'
export async function generateStaticParams() {
return getAllPostSlugs().map((slug) => ({ slug }))
}
export const dynamicParams = false
export async function generateMetadata({
params,
}: {
params: Promise<{ slug: string }>
}): Promise<Metadata> {
const { slug } = await params
const { meta } = await getPostBySlug(slug)
return pageMetadata({
title: meta.title,
description: meta.description,
path: `/posts/${slug}`,
image: `/posts/${slug}/opengraph-image`,
openGraph: {
type: 'article',
publishedTime: meta.date,
modifiedTime: meta.updated,
authors: [AUTHOR.url],
section: meta.category,
tags: meta.tags,
},
})
}
export default async function Post({ params }: { params: Promise<{ slug: string }> }) {
const { slug } = await params
const { meta, content, tableOfContents } = await getPostBySlug(slug)
const { next, previous } = getNextAndPreviousPosts(slug)
const url = `${SITE_URL}/posts/${slug}`
const jsonLd = {
'@context': 'https://schema.org',
'@type': 'BlogPosting',
headline: meta.title,
description: meta.description,
url,
mainEntityOfPage: url,
datePublished: meta.date,
dateModified: meta.updated ?? meta.date,
image: `${url}/opengraph-image`,
articleSection: meta.category,
keywords: meta.tags.join(', '),
author: { '@type': 'Person', name: AUTHOR.name, url: AUTHOR.url },
publisher: { '@type': 'Person', name: AUTHOR.name, url: AUTHOR.url },
isPartOf: { '@type': 'Blog', name: SITE_NAME, url: SITE_URL },
}
return (
<main className="flex w-full">
<script
type="application/ld+json"
// Escape "<" so post content can never close the script tag early
dangerouslySetInnerHTML={{ __html: JSON.stringify(jsonLd).replace(/</g, '\\u003c') }}
/>
<article className="max-w-3xl 2xl:max-w-4xl mx-auto px-4 py-8 mb-8 lg:py-16 min-w-0">
{meta.category && (
<Link
href={`/categories/${slugify(meta.category)}`}
className="text-accent hover:underline font-sm mb-2 inline-block"
>
{meta.category}
</Link>
)}
<h1 className="text-4xl font-bold mb-4">{meta.title}</h1>
<div className="flex justify-between md:justify-normal items-center gap-2 text-fg-dim mb-4 border-y border-border py-2 px-2 md:px-4 text-sm">
<div className="flex items-center gap-2">
<span className="hidden md:inline">Posted</span>
<span className="md:hidden">
<SendHorizonal className="w-3 h-3" />
</span>
<time
dateTime={meta.date}
title={dateTimeFormatter.format(new Date(meta.date))}
className="font-semibold"
>
{shortDateFormatter.format(new Date(meta.date))}
</time>
</div>
<span className="hidden md:inline">&middot;</span>
{meta.updated && (
<>
<div className="flex items-center gap-2">
<span className="hidden md:inline">Updated</span>
<span className="md:hidden">
<Pencil className="w-3 h-3" />
</span>
<time
dateTime={meta.updated}
title={dateTimeFormatter.format(new Date(meta.updated))}
className="font-semibold"
>
{shortDateFormatter.format(new Date(meta.updated))}
</time>
</div>
<span className="hidden md:inline">&middot;</span>
</>
)}
<span>{meta.readingTimeText}</span>
</div>
<p className="text-fg text-lg mb-4">{meta.description}</p>
{process.env.NODE_ENV === 'development' && (
<span className="text-fg-dim text-sm mb-4 block">
Description has {meta.description.length} characters, which is{' '}
{meta.description.length < 120
? 'too short'
: meta.description.length > 160
? 'too long'
: 'just right'}{' '}
for SEO.
</span>
)}
{meta.coverImage && (
<ImageWrapper src={meta.coverImage} alt={meta.coverImageAlt} priority />
)}
<div className="prose">{content}</div>
{meta.tags.length > 0 && (
<div className="mt-6 border-t border-border pt-4 flex gap-2 items-center flex-wrap">
<h2 className="text-lg font-bold">Tags</h2>
<div className="flex flex-wrap gap-1">
{meta.tags.map((tag) => (
<Link
key={tag}
href={`/tags/${slugify(tag)}`}
className="bg-accent/20 text-accent px-3 py-1 rounded-full text-xs hover:bg-accent/30 transition-colors"
>
{tag}
</Link>
))}
</div>
</div>
)}
<div className="mt-8 mx-auto flex">
<ShareLinks url={url} title={meta.title} description={meta.description} />
</div>
<div className="mt-12 grid grid-cols-1 sm:grid-cols-2 gap-3 sm:gap-4 border-t border-border pt-8">
{previous ? (
<Link
href={`/posts/${previous.slug}`}
className="group flex flex-col gap-1 rounded-lg p-4 transition-colors hover:bg-fg/10 active:bg-fg/15"
>
<span className="flex items-center gap-1 text-xs text-fg-dim uppercase tracking-wide">
<ArrowLeft className="w-3 h-3 shrink-0 transition-transform group-hover:-translate-x-1" />
Previous
</span>
<span className="text-accent font-medium group-hover:underline line-clamp-2">
{previous.title}
</span>
</Link>
) : (
<div className="hidden sm:block" />
)}
{next ? (
<Link
href={`/posts/${next.slug}`}
className="group flex flex-col gap-1 rounded-lg p-4 transition-colors hover:bg-fg/10 active:bg-fg/15 sm:text-right"
>
<span className="flex items-center gap-1 text-xs text-fg-dim uppercase tracking-wide sm:justify-end">
Next
<ArrowRight className="w-3 h-3 shrink-0 transition-transform group-hover:translate-x-1" />
</span>
<span className="text-accent font-medium group-hover:underline line-clamp-2">
{next.title}
</span>
</Link>
) : (
<div className="hidden sm:block" />
)}
</div>
</article>
<TableOfContents items={tableOfContents} />
</main>
)
}