Split to Error resposen and Success Response about expr HOT 5 CLOSED

First thing first, http errors are all about proper http code, so we should start designing error handler by http error code specification and errors thrown from controller, should include desired http error code (and error message) @adiferd

from expr.

for now, i use restify error event handler to handle exception in controller (i use restify for day to day work). Restify error handler wrapped in ErrorMap class. Node.js utilize next() method to move process to next chain, so the wrapper method called within node.js next method

return next(ErrorMap.mapping(error.status || 500, error.message || 'Internal server error'));

See this error map method snippet for reference

'use strict'
const errs = require('restify-errors');

class ErrorMap {
	static mapping (code, message = null) {
		const errorList = {
			400: 'BadRequestError',
			401: 'UnauthorizedError',
			403: 'ForbiddenError',
			404: 'NotFoundError',
			405: 'MethodNotAllowedError',
			408: 'RequestTimeoutError',
			413: 'RequestEntityTooLargeError',
			500: 'InternalServerError'
		};

		return new errs[errorList[code]](message);
	}	
}

module.exports= ErrorMap;

Since we are building this thing on top of express, we can't use restify's error handler event. Unfortunately, things going quite different in express for no error events are available, per this docs provided by express.

https://expressjs.com/en/guide/error-handling.html

So no other way than build error handler method by ourself @adiferd

from expr.

the next method called within exception in try catch block, which is the catch scope

from expr.

I think, I can start with refactor this function

'use strict'

class Formatter {
	static toSingleResponse(data, message, error) {
		return {
			  result: data
			, message: message
			, error: (error!=null)?error:null
		};
	}

remove the error key from the return and build the ErrorMapper Function

toSingleResponse will be used only to return success reponse, on the other hand errorMapper will be used to return error message on API request. what do you think @firyalff ?

from expr.

this is good, since we're gonna move error response formater to separated module, +1 for this @adiferd

from expr.