qvac-lib-error-base

This library provides standardized error handling capabilities for all QVAC libraries. It ensures consistency in error reporting, serialization, and handling across the entire QVAC ecosystem.

Installation

npm i git+https://github.com/tetherto/qvac-lib-error-base.git

Features

• Base error class extending native Error
• Standardized error codes and messages
• Support for dynamic error messages with parameters
• Error serialization for logging and API responses
• Registry system for error code management
• Mechanisms to prevent error code conflicts

Usage

Basic Usage

const { QvacErrorBase, addCodes } = require('@qvac/error-base')

// Create your own error class extending the base
class QvacErrorCustom extends QvacErrorBase {
  constructor(code, adds) {
    super(code, adds)
  }
}

// Define your error codes (reserve at least 1000 codes per library)
const ERR_CODES = Object.freeze({
  VALIDATION_ERROR: 1000,
  CONNECTION_ERROR: 1001,
  TIMEOUT_ERROR: 1002
})

// Register your error codes and their messages
addCodes({
  [ERR_CODES.VALIDATION_ERROR]: {
    name: 'VALIDATION_ERROR',
    message: (...field) => `Validation failed for field: ${field}`
  },
  [ERR_CODES.CONNECTION_ERROR]: {
    name: 'CONNECTION_ERROR',
    message: 'Failed to establish connection'
  },
  [ERR_CODES.TIMEOUT_ERROR]: {
    name: 'TIMEOUT_ERROR',
    message: (timeout) => `Operation timed out after ${timeout}ms`
  }
})

// Using your custom errors
try {
  // Some operation that fails
  throw new QvacErrorCustom(ERR_CODES.VALIDATION_ERROR, 'username')
} catch (error) {
  console.error(error.message) // "Validation failed for field: username"
  console.error(error.code)    // 1000
  console.error(error.name)    // "VALIDATION_ERROR"
}

Error Code Conventions

• Each library should reserve a range of at least 1000 codes
• Keep codes in ascending order based on abstraction level
• Base libraries should have lower code ranges
• Document your code range to avoid conflicts with other libraries

API Reference

QvacErrorBase

Base error class that extends the native Error.

new QvacErrorBase(code, adds)

• code (Number): The error code
• adds (Array|String): Additional parameters to format the error message

addCodes(codes)

Register new error codes.

• codes (Object): Map of error codes to their definitions

getRegisteredCodes()

Get all registered error codes and their definitions.

isCodeRegistered(code)

Check if a code is already registered.

• code (Number): The error code to check

INTERNAL_ERROR_CODES

Reserved internal error codes:

• UNKNOWN_ERROR_CODE: 0
• INVALID_CODE_DEFINITION: 1
• ERROR_CODE_ALREADY_EXISTS: 2
• MISSING_ERROR_DEFINITION: 3

Development

After cloning, run npm install. If npm lifecycle scripts are disabled, also run npm run prepare to initialize git hooks.

Best Practices

1. Create a dedicated errors file/module in each library
2. Extend QvacErrorBase with a library-specific class name (e.g., QvacErrorAgent)
3. Keep all error codes in a separate, well-documented module
4. Use descriptive error names and clear messages
5. Avoid relying on error messages for logic (use codes instead)
6. Consider generating documentation from your error codes