Errors from the server

serverErrorsFrom(body, options?) turns the answer of a backend that refused a submit into errors by field path, ready for a form store's setServerErrors:

import {
  collectFieldPaths,
  FORM_ERROR_KEY,
  serverErrorsFrom,
} from '@dynamic-field-kit/core';

serverErrorsFrom(
  { errors: { Email: ['Already registered'] } },
  { paths: collectFieldPaths(fields, data) },
);
// { email: ['Already registered'] }

serverErrorsFrom({
  errors: [
    { pointer: '/contacts/1/phone', detail: 'Not a phone number' },
    { message: 'The order is closed' },
  ],
});
// { 'contacts[1].phone': ['Not a phone number'], [FORM_ERROR_KEY]: ['The order is closed'] }

It reads a map of field to message or messages; that map under errors or fieldErrors (with formErrors beside it); and a list under errors or issues whose items name their field as field, path, name, property, param, pointer or source.pointer and carry a message, detail, msg or constraints. A JSON Pointer, a dotted path, a JSONPath and a list of segments all become the path the kit uses (contacts[1].phone). With paths, a key that differs from a form field only by case takes that field's spelling. Errors that name no field are kept under FORM_ERROR_KEY. A body that is not a set of field errors answers an empty object.