Eratum

Installation

npm install --save eratum

Usage

Import

// Old way
const { default: Errors, registerError } = require('eratum');

// Module way
import Errors, { registerError } from 'eratum';

Throw

import Errors from 'eratum';

const error = Errors.notYetImplemented({ name: 'awesomeFeature', reason: 'Planned in v2.3' });
/*
{
	tag: 'NOT_YET_IMPLEMENTED',
	message: 'NOT_YET_IMPLEMENTED - Feature(awesomeFeature) is not yet implemented.Planned in v2.3'
}
*/

try {
	try {
		throw Errors.notEqual({ name: 'key.length', actualValue: 16, expectedValue: 32 });
	} catch (cause) {
		throw Errors.unexpectedError({ reason: 'Cipher fail', origin: 'CRYPTO', cause })
	}
} catch (cause) {
	throw Errors.internalError({ reason: 'Authentication fail', origin: 'LOGIN', cause })
}
/*
{
	tag: 'INTERNAL_ERROR',
	message: 'INTERNAL_ERROR - Authentication fail',
	origin: 'LOGIN'
	cause: {
		tag: 'UNEXPECTED_ERROR',
		message: 'UNEXPECTED_ERROR - Cipher fail',
		origin: 'CRYPTO'
		cause: {
			tag: 'NOT_EQUAL',
			message: 'NOT_EQUAL - key.length(16) is not equal to 32'
		},
	},
}
*/

Extends

import Errors, { registerError } from 'eratum';

registerError('outOfBound', 'Resource(<%= name %>) is out of bound(<%= bound %>)', [ 'name', 'bound' ] );
// Errors.outOfBound.tag === 'OUT_OF_BOUND'

const error = Errors.outOfBound({ name: 'amount', bound: 10 });
// error instanceof Errors.outOfBound.class === true
// error.tag === 'OUT_OF_BOUND'

// Optional parameters
registerError('notYetImplemented', 'Feature(<%- name %>) is not yet implemented.<% if (locals.reason) { %><%- reason %><% } %>', ['name']);

Documentation

Eratum

Class extending Error

• Properties
  • tag String Unique string identifier for this error type. Must be capitalized snake case (/^[A-Z_]+$/). Generated from name when using registerError.
  • message String Human readable message explaining error. Generated by EJS template and parameters. Inherited from Error.
  • cause any Previous Error generating this one. (optional, default null)
  • origin String Human readable hint about thrower. Should be capitalized snake case (/^[A-Z_]*$/). (optional, default '')
  • parameters Object Object storing extra parameters while producing this Eratum (including required attributes).
• Static properties
  • origin String Prefix for all generated errors.
  • isStackEnabled boolean Define default option for get function.
• Functions
  • get Serilize error in JSON ready object.
    • Parameters
      • isStackEnabled boolean Define if stack is includes in returns. (optional, default Eratum.isStackEnabled)
    • Returns IEratum

IEratum

Interface defining properties of Eratum class

• Properties
  • tag String Unique string identifier for this error type. Must be capitalized snake case (/^[A-Z_]+$/).
  • message String Human readable message explaining error.
  • cause any Previous Error generating this one.
  • origin String Human readable hint about thrower. Should be capitalized snake case (/^[A-Z_]*$/).

registerError

Register error by name

• Parameters
  • name String Unique string name for this error type. Must be camel case (/^[a-z][a-zA-Z]*$/).
  • template String EJS template to build error message. (optional, default '')
  • requiredAttrs String[] Required attributes for previous EJS template. Rendering fail if those attributes are undefined. (optional, default [])
• Return void
• Throw Eratum.doesntExist if missing parameter
• Throw Eratum.invalidType if type parameter missmatch
• Throw Eratum.invalidFormat if format parameter missmatch
• Throw Eratum.exist if error name is already registered

Error producer

All errors have the same producer signature.

• Parameters
  • parameters EratumOptions
  • parameters.cause any
  • parameters.origin String ****
  • parameters[...requiredAttrs] Stringable
• Return class extending Eratum
• Throw Eratum.doesntExist if missing parameters or required attributes.
• Throw Eratum.invalidType if type parameter missmatch

Registered errors

• internalError
  • Tag INTERNAL_ERROR
  • Parameters
    • reason (optional, default '')
• unexpectedError
  • Tag UNEXPECTED_ERROR
  • Parameters
    • reason (optional, default '')
• programingFault
  • Tag PROGRAMING_FAULT
  • Parameters
    • reason (optional, default '')
• notYetImplemented
  • Tag NOT_YET_IMPLEMENTED
  • Parameters
    • name
    • reason (optional, default '')
• initialized
  • Tag INITIALIZED
  • Parameters
    • name
• notInitialized
  • Tag NOT_INITIALIZED
  • Parameters
    • name
• invalid
  • Tag INVALID
  • Parameters
    • name
    • reason (optional, default '')
• invalidType
  • Tag INVALID_TYPE
  • Parameters
    • name
    • actualType
    • expectedType
• invalidFormat
  • Tag INVALID_FORMAT
  • Parameters
    • name
    • value
    • format
• exist
  • Tag EXIST
  • Parameters
    • name
• doesntExist
  • Tag DOESNT_EXIST
  • Parameters
    • name
• equal
  • Tag EQUAL
  • Parameters
    • name
    • value
• notEqual
  • Tag NOT_EQUAL
  • Parameters
    • name
    • actualValue
    • expectedValue
• included
  • Tag INCLUDED
  • Parameters
    • name
    • value
    • forbiddenValues
• notIncluded
  • Tag NOT_INCLUDED
  • Parameters
    • name
    • value
    • possibleValues