Throwing

import { Exception2, exception2Types } from 'exception2';

throw new Exception2({
  // exceptionKey is camelCase string to strictly and
  // easily identify exception and to use as i18n key
  exceptionKey: 'someKey1',
  
  // data is object to pass everything you want to pass
  // to catcher or to frontend from backend
  data: { userIdHavingThisError: 1 },

  // Optional property to map into http error codes when needed
  exceptionTypeKey: exception2Types.validation,
});

When using on backend and requiring defining http status of error, use optional exceptionTypeKey and httpStatusByExceptionType for mapping to https codes

Handling

You want to know if caught exception is exception2 When catching within same application use instanceOf Exception2 When getting it serialized from another api use isSerializedException When you catch unknown exception use getCaughtExceptionMessage to either read its message or exceptionKey If you want to unify unknown caught exception to Exception2, use toException. It will put the passed exception to data.