urql-array-mutations-hook

urql-array-mutations-hook

Mutate arrays in response to urql operations

React hook for combining the results from useQuery and useMutation. Meant for this scenario:

• You fetch an array of objects from a graphql server
• You send requests to modify that array on the server
• You want to sync the local array without re-requesting the whole darn thing

Example

import { useArrayMutations } from 'urql-array-mutations-hook'
import List from './ListComponent'

function ListWithGraphql ({ options }) {
  const [array, add, remove] = useArrayMutations(options)
  // These functions mutate the array,
  // which triggers a render cycle
  const addItem = add[1]
  const removeItem = remove[1]
  return (
    <List
      items={array}
      addItem={addItem}
      removeItem={removeItem}
    />
  )
}

Options

The input for useArrayMutations is an object with these properties:

• key

  • String | Function

  • Each array element must be an object with a unique key value. By default, it uses the id property from each object, but the key option makes this customizable. When using a function, it takes one item as input, and must return the key value for that item.

• get

  • String | Object

  • Input for useQuery; a string can be used as shorthand for the query property

• add

  • String

  • Input for useMutation; the operation result must include a key for the added item

• remove

  • String

  • Input for useMutation; the operation result must include a key for the removed item

• sort

  • Function

  • Invoked whenever the array is modified. It takes a single parameter (the array), and must return a sorted version.

Check here for examples of get, add, and remove.

Return Value

The return value is an array of arrays:

const [array, add, remove, query] = useArrayMutations(options)

• [0] - the current array, made by combining any graphql responses

• [1] - return value from useMutation(...options.add)

• [2] - return value from useMutation(...options.remove)

• [3] - return value from useQuery(...options.query)