freddi301/flow-validator

// @flow

import { Type } from "./Type";
import { AsyncType } from "../async/AsyncType";

export type Errors = { [key: string]: ValidationError };
export type ValidationErrorPayload = {
  expected: Type<any> | AsyncType<any>,
  got: mixed,
  errors?: Errors,
  description?: string
};
export type ValidationErrorJSONPayload = {
  expected: { name: string },
  description?: string,
  got: any,
  errors?: { [key: string]: ValidationErrorJSONPayload }
};
export class ValidationError extends Error {
  payload: ValidationErrorPayload;
  constructor(payload: ValidationErrorPayload) {
    super("ValidationError");
    this.payload = payload;
  }
  toJSON(): ValidationErrorJSONPayload {
    const payload: ValidationErrorJSONPayload = {
      expected: this.payload.expected.toJSON(),
      got: this.payload.got
    };
    if (this.payload.description)
      payload.description = this.payload.description;
    if (this.payload.errors) {
      const errors = {};
      for (const key of Object.keys(this.payload.errors)) {
        errors[key] = this.payload.errors[key].toJSON();
      }
      payload.errors = errors;
    }
    return payload;
  }
}