api-types.ts

import * as t from 'io-ts';
function request<P extends t.Props>(type:string, props:P) {
  return t.type({
    type: t.literal(type),
    props: t.type(props)
  });
}
export const RequestT = t.union([
  request('foo', {
    baz: t.string,
    quux: t.array(t.string)
  }),
  request('bar', {
    a: t.number,
    b: t.string
  })
]);
export type Request = t.TypeOf<typeof RequestT>;
export const ResponseT = t.union([
  t.type({})
])
export type Response = t.TypeOf<typeof ResponseT>;