svelte-qparam

🔎 Type-Safe Query Parameter for SvelteKit

Demo

Installation

npm i svelte-qparam

Bulk Parameters

Use the define function to set multiple parameter definitions at once.

<script>
  import { page } from '$app/state'
  import { define } from 'svelte-qparam'
  import { string, number, boolean } from 'svelte-qparam/serde'

  const extract = define({
    str: string,
    num: number,
    bool: boolean
  })

  // https://example.com/?str=value&num=123&bool=false
  let { values, qparams: q } = $derived(extract(page.url))

  // {
  //   str: 'value',
  //   num: 123,
  //   bool: false
  // }
  console.log(values)

  // output 'value'
  console.log(q.str)
  q.num = 456
  q.bool = true
</script>

Fullstack Type-Safety

Values defined with the define function can be used in +page.js and +page.server.js. This allows you to handle parameters type-safely across applications across servers and clients.

// +page.js
import { define } from 'svelte-qparam'
import { string, number, boolean } from 'svelte-qparam/serde'

export const _extract = define({
  str: string,
  num: number,
  bool: boolean
})

export const load = ({ url, data }) => {
  const { values, qparams } = _extract(url)

  // ...

  return {
    qparams
  }
}

// +page.server.js
import { _extract } from './+page.js'

export const load = ({ url }) => {
  const { values } = _extract(url)

  // ...

  return {
    // Note: Cannot return `qparams` from server
    // ...
  }
}

<!-- +page.svelte -->
<script>
  let { data } = $props()

  let { qparams: q } = $derived(data)

  // ...
</script>

License

MIT