ErrorMsg

@tsed/schema

Usage

import { ErrorMsg } from "@tsed/schema";

See /packages/specs/schema/src/decorators/common/errorMsg.ts.

Overview

function ErrorMsg(obj: Record<string, string>): (...args: any[]) => any;

• obj (Record<string): - Object mapping validation keywords to custom error messages

Description

Adds custom error messages for validation failures using ajv-errors.

The @ErrorMsg() decorator allows specifying custom error messages that override the default validation error messages. This requires the ajv-errors plugin to be configured with your AJV validator.

Basic Usage

class UserModel {
  @ErrorMsg({ required: "Username is required" })
  @Required()
  username: string;
}

Multiple Validation Errors

class PasswordModel {
  @ErrorMsg({
    required: "Password is required",
    minLength: "Password must be at least 8 characters",
    pattern: "Password must contain letters and numbers"
  })
  @Required()
  @MinLength(8)
  @Pattern(/^(?=.*[A-Za-z])(?=.*\d)/)
  password: string;
}

Use Cases

• User-Friendly Messages: Replace technical validation errors with clear messages
• Localization: Provide translated error messages
• Business Context: Add domain-specific error descriptions
• API Consistency: Standardize error message formats

Important Notes

• Requires ajv-errors plugin to be installed and configured
• Keys should match the validation keywords (required, minLength, etc.)
• Messages are stored as custom schema keys