@untemps/jsend-wrapper

Class to wrap an HTTP response in a JSend Specification format.

The status string (success, fail, error) is calculated along with the HTTP status code of the response:

• If the status code is greater or equal to 500, status is set to error
• If the status code is greater or equal to 400 and strictly lower to 500, status is set to fail
• Otherwise, status is set to success

Installation

yarn add @untemps/jsend-wrapper

Usage

Import JSendWrapper:

import { JSendWrapper } from '@untemps/jsend-wrapper'

Create an instance of JSendWrapper:

const jsend = new JSendWrapper()

Call the wrap method passing two mandatory and two optional arguments:

jsend.wrap([statusCode], [body], [errorCode], [errorData])

wrap Method Arguments

| Parameter | Type | Description | | ---------- | ------ | ------------------------------------------------------------------------ | | statusCode | number | HTTP code of the response | | body | any | Body of the response. Depending of the status (see below) | | errorCode | number | (Optional) A numeric code corresponding to the error | | errorData | any | (Optional) A generic container for any other information about the error |

The body Argument

The type of the body argument depends on the status:

| Status | Type | Description | | --------- | ------ | ---------------------------------------------------------------------------------------- | | success | any | Data returned by the HTTP request. If the call returns no data, data is set to null. | | fail | object | Hash of key/value pairs explaining what went wrong in the HTTP request (validation, ...) | | error | string | Meaningful, end-user-readable message, explaining the reason of the error |

Formatted Result

Success

{
    status: 'success',
    data: {
        post: {
            id: 1,
            title: 'A blog post',
            body: 'Some useful content'
        }
     }
}

Fail

{
    status: 'fail', 
    data: {
    	title: 'A title is required'
    }
}

Error

{
    status: 'error', 
    message: 'Unable to communicate with database'
}

JSendError

A JSendError class is provided to help throwing specific JSend errors.

The constructor accepts either plain message, code, data arguments or a JSendResponse object:

import { JSendError } from '@untemps/jsend-wrapper'

throw new JSendError('HTTP Error', 500, { someValue: 42 })
throw new JSendError({ status: 'error', message: 'HTTP Error', code: 500, data: { someValue: 42 })

Types

Besides the class wrapper, the lib exports the definitions for the response type (TJSendResponse) and the status enum (EJSendStatus).

TJSendResponse

status: EJSendStatus
data?: any
message?: string,
code?: number

EJSendStatus

SUCCESS = 'success'
FAIL = 'fail'
ERROR = 'error'

For more information about the JSend Spec, see the GitHub README here : https://github.com/omniti-labs/jsend