block-content-to-html

Render an array of block text from Sanity to HTML.

Installing

npm install --save @sanity/block-content-to-html

Usage

const blocksToHtml = require('@sanity/block-content-to-html')
const client = require('@sanity/client')({
  projectId: '<your project id>',
  dataset: '<some dataset>',
  apiVersion: '2021-03-25',
  useCdn: true
})

// `h` is a way to build HTML known as hyperscript
// See https://github.com/hyperhype/hyperscript for more info
const h = blocksToHtml.h

const serializers = {
  types: {
    code: props => (
      h('pre', {className: props.node.language},
        h('code', props.node.code)
      )
    )
  }
}

client.fetch('*[_type == "article"][0]').then(article => {
  const el = blocksToHtml({
    blocks: article.body,
    serializers: serializers
  })

  document.getElementById('root').appendChild(el)
})

Options

• className - When more than one block is given, a container node has to be created. Passing a className will pass it on to the container. Note that if only a single block is given as input, the container node will be skipped.
• serializers - Specifies the functions to use for rendering content. Merged with default serializers.
• serializers.types - Serializers for block types, see example above
• serializers.marks - Serializers for marks - data that annotates a text child of a block. See example usage below.
• serializers.list - Function to use when rendering a list node
• serializers.listItem - Function to use when rendering a list item node
• serializers.hardBreak - Function to use when transforming newline characters to a hard break (<br/> by default, pass false to render newline character)
• serializers.unknownType - Override the default serializer for blocks of unknown type, if ignoreUnknownTypes is set to false (the default).
• serializers.unknownMark - Override the default serializer for marks of unknown type. Defaults to a span without any styling.
• imageOptions - When encountering image blocks, this defines which query parameters to apply in order to control size/crop mode etc.
• ignoreUnknownTypes - By default (or when setting this property explicitly to true) it will output a hidden <div> with a warning. By setting this property to false, the renderer will throw an error when encountering unknown block types. The behavior of the unknown type rendering can be customized by specifying a serializer with serializers.unknownType.

In addition, in order to render images without materializing the asset documents, you should also specify:

• projectId - The ID of your Sanity project.
• dataset - Name of the Sanity dataset containing the document that is being rendered.

Examples

Rendering custom marks

const input = [{
  _type: 'block',
  children: [{
    _key: 'a1ph4',
    _type: 'span',
    marks: ['s0m3k3y'],
    text: 'Sanity'
  }],
  markDefs: [{
    _key: 's0m3k3y',
    _type: 'highlight',
    color: '#E4FC5B'
  }]
}]

const highlight = props => (
  h('span', {style: {backgroundColor: props.mark.color}}, props.children)
)

const content = blocksToHtml({
  blocks: input,
  serializers: {marks: {highlight}}
})

Specifying image options

blocksToHtml({
  blocks: input,
  imageOptions: {w: 320, h: 240, fit: 'max'},
  projectId: 'myprojectid',
  dataset: 'mydataset',
})

Customizing default serializer for block-type

const BlockRenderer = props => {
  const style = props.node.style || 'normal'

  if (/^h\d/.test(style)) {
    const level = style.replace(/[^\d]/g, '')
    return h('h2', {className: `my-heading level-${level}`}, props.children)
  }

  return style === 'blockquote'
    ? h('blockquote', {className: 'my-block-quote'}, props.children)
    : h('p', {className: 'my-paragraph'}, props.children)
}

blocksToHtml({
  blocks: input,
  serializers: {types: {block: BlockRenderer}}
})

License

MIT-licensed. See LICENSE.