Examples for writing good serializers for React?
I totally get it—serializers can be confusing at first! The package readme can be a bit terse. Let me break it down with some practical examples.
The @portabletext/react package uses a "components" prop (they call them serializers/components interchangeably) to customize how different parts of your Portable Text render. Here's the key thing to understand: the structure of your components object mirrors the structure of your Portable Text.
Basic Structure
import {PortableText} from '@portabletext/react'
const components = {
types: {
// Custom block types (images, code blocks, etc.)
},
marks: {
// Inline formatting (bold, links, highlights, etc.)
},
block: {
// Paragraph styles and headings
},
list: {
// Bullet and numbered lists
}
}
<PortableText value={portableTextContent} components={components} />Practical Examples
Custom headings and paragraphs:
const components = {
block: {
h1: ({children}) => <h1 className="text-4xl font-bold">{children}</h1>,
h2: ({children}) => <h2 className="text-3xl">{children}</h2>,
normal: ({children}) => <p className="my-4">{children}</p>
}
}Custom marks (inline formatting):
const components = {
marks: {
link: ({value, children}) => {
const target = value?.href?.startsWith('http') ? '_blank' : undefined
return <a href={value?.href} target={target} rel={target && 'noopener'}>{children}</a>
},
highlight: ({children}) => <span className="bg-yellow-200">{children}</span>
}
}Custom types (block-level content):
const components = {
types: {
image: ({value}) => (
<img
src={value.url}
alt={value.alt || ' '}
loading="lazy"
/>
),
callout: ({value}) => (
<div className="bg-blue-100 p-4 rounded">
{value.text}
</div>
)
}
}Important Migration Note
If you're coming from the old @sanity/block-content-to-react, the main change is that node is now value in your component props. This trips people up constantly!
Complete Example
const myPortableTextComponents = {
types: {
image: ({value}) => <img src={value.imageUrl} />,
callToAction: ({value}) => <button>{value.text}</button>
},
marks: {
link: ({children, value}) => <a href={value.href}>{children}</a>,
strong: ({children}) => <strong className="font-bold">{children}</strong>
},
block: {
h1: ({children}) => <h1 className="text-5xl">{children}</h1>,
blockquote: ({children}) => <blockquote className="border-l-4">{children}</blockquote>
},
list: {
bullet: ({children}) => <ul className="list-disc ml-4">{children}</ul>,
number: ({children}) => <ol className="list-decimal ml-4">{children}</ol>
}
}Check out this comprehensive guide on customizing Portable Text for more detailed examples, including how to match your serializers to your schema definitions.
The key insight: each component receives either children (for wrappers like marks and blocks) or value (for custom types where you need the actual data). Once that clicks, everything else falls into place!
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