json-type-check A typechecker for JSON import Jst from 'json-type-check' const value = { requiredString: 'foo'} const schema = Jst.shape({ requiredString: [ Jst.string, Jst.required ], optionalInteger: Jst.integer, optionalDate: Jst.date, optionalEnum: Jst.oneOf([ Jst.integer, Jst.string ])}) const check = new Jst(value, schema) console.log(check.valid) // true console.log(check.errors) // []