Delete

Describes entities to be marked as DELETED. This is a special symbol.

• entity which entity to delete. The input is used to compute the pk() for lookup.

Usage

Normalize

// Example data response
const data = { users: [{ id: '123' }, { id: '543' }] };

class User extends Entity {
  readonly name: string = '';
  pk() {
    return this.id;
  }
}
const deleteSchema = { users: [new schema.Delete(User)] };

const normalizedData = normalize(data, deleteSchema);

Output

{
  entities: {
    User: { '123': DELETED, '543': DELETED }
  },
  result: { User: [ '123', '543' ] }
}

Batch Deletes

Here we add another endpoint for deleting many entities at a time. Here we pass in a list of ids, and the response is an empty string.

Constructing an article response using the params argument in fetch empowers the normalized cache to know which entities to delete when the request is success, or if optimistic updates are used.

import { Resource, schema } from '@rest-hooks/rest';

class MyResource extends Resource {
  static deleteList<T extends typeof MyResource>(this: T) {
    const init = this.getFetchInit({ method: 'DELETE' });
    return new Endpoint(
      (params: readonly string[]) =>
        this.fetch(this.url(params).then(() => params.map(id => ({ id })))),
      {
        ...this.getEndpointExtra(),
        schema: [new schemas.Delete(this)],
      },
    );
  }
}

function MyTable() {
  const { selectedIds } = useFields(TableForm);
  const list = useResource(MyResource.list(), {});
  const delMany = useFetcher(MyResource.deleteList());

  return (
    <div>
      <header>
        <span>My Table</span>
        <button onClick={() => delMany(selectedIds)}>Delete</button>
      </header>
      <TableBody data={list} form={TableForm} />
    </div>
  );
}

Impact on useResource()

When entities are deleted in a result currently being presented in React, useResource() will consider them invalid

• For optional Entities, they are simply removed
• For required Entities, this invalidates the entire response re-triggering suspense.