Extendable Http Errors

Introduction

Error creator for creating custom made and common HTTP errors for node application. Each http error contains the http status. The user can define the error code for the application to identify.

Implemented Http Errors

• BadRequestError
• ForbiddenError
• ImATeapot
• InternalServerError
• NotFoundError
• NotImplementedError
• ServiceUnAvailable
• UnauthorizedError

Installation

npm install extendable-http-errors --save

Code Samples

• Use specific http error
• Make all errors global
• Custom Http Error
• Convert error to object to send to the client
• Convert error to object
• Wrap if not wrapped unknown error

Use specific http error:

const httpErrors = require('extendable-http-errors').httpErrors;

//No need to change status it got the default type of http error status
function (req, res, next) {    
    let errMsg = "Error Route Not Found";
    let section = "Routes";
    let code = 9404; //error code for the client to identify the error
    let params = {url: req.url};
    
    let err = new httpErrors.NotFoundError(errMsg, section, code, params);
    next(err);
}

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Make all errors global

require('extendable-http-errors').initGlobalErrors();

console.log(new InternalServerError("Internal Server Error", "Core", 9500)); 

InternalServerError: Interl Server Error
  at /Users/Username/WebstormProjects/Project/app.js:12:15
  at Layer.handle [as handle_request] (/Users/Username/WebstormProjects/Project/node_modules/express/lib/router/layer.js:95:5)
  at next (/Users/Username/WebstormProjects/Project/node_modules/express/lib/router/route.js:131:13)
  at Route.dispatch (/Users/Username/WebstormProjects/Project/node_modules/express/lib/router/route.js:112:3)
  at Layer.handle [as handle_request] (/Users/Username/WebstormProjects/Project/node_modules/express/lib/router/layer.js:95:5)
  at /Users/Username/WebstormProjects/Project/node_modules/express/lib/router/index.js:277:22
  at Function.process_params (/Users/Username/WebstormProjects/Project/node_modules/express/lib/router/index.js:330:12)
  at next (/Users/Username/WebstormProjects/Project/node_modules/express/lib/router/index.js:271:10)
  at expressInit (/Users/Username/WebstormProjects/Project/node_modules/express/lib/middleware/init.js:33:5)
code: 9500,
section: 'Core',
uuid: '8a77fc8b-601c-4fbb-89df-570ced4fa42b'

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Custom http error

Before changing the 'this', need to call the super method so the new extended error could be changed.

const extendableHttpErrors = require('extendable-http-errors');

class BadLoginRequest extends extendableHttpErrors.httpErrors.BadRequestError {
    constructor(msg, section, code, reason){
        reason = reason.toUpperCase();
        super(msg, section, code, {reason: reason});
    }
}

const customErrors = {
    BadLoginRequest
};

extendableHttpErrors.initGlobalErrors(customErrors);

console.log(new BadLoginRequest("Bad Login Request!", "SpecialLogin", 9876, "User is not special enough"));

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Convert error to object to send to the client

const extendableHttpErrors = require('extendable-http-errors');

const app = express();
const customErrors = {
    CustomError: require('./errors/custom-error')
};

extendableHttpErrors.initGlobalErrors(customErrors);

app.use(extendableHttpErrors.prettifyErrorMiddleware);

app.get('/', function (req, res, next) {
    let err = new CustomError("Custom Error!!", "Custom", 9876, "User is not custom enough");
    next(err);
});

//Error Handler
app.use(function (err, req, res, next) {
    res.status(err.status).json(err);
});

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Convert error to object

const extendableHttpErrors = require('extendable-http-errors');

const app = express();
const customErrors = {
    CustomError: require('./errors/custom-error')
};

extendableHttpErrors.initGlobalErrors(customErrors);

app.get('/', function (req, res, next) {
    let err = new CustomError("Custom Error!!", "Custom", 9876, "User is not custom enough");
    next(err);
});

//Error Handler
app.use(function (err, req, res, next) {
    err = extendableHttpErrors.prettifyErrorFunction(err);
    res.status(err.status).json(err);
});

Wrap if not wrapped unknown error

If the error is already created from the extendable-http-errors it will return it self, otherwise it will create new extendable-http-errors Error with the message of the new error.

const extendableHttpErrors = require('extendable-http-errors');

const app = express();
const customErrors = {
    CustomError: require('./errors/custom-error')
};

extendableHttpErrors.initGlobalErrors(customErrors);

app.use(extendableHttpErrors.prettifyErrorMiddleware);

app.get('/', function (req, res, next) {
    let err = new CustomError("Custom Error!!", "Custom", 9876, "User is not custom enough");
    next(err);
});

//Error Handler
app.use(function (err, req, res, next) {
    //If error is already created from the extendable-errors,
    //it will throw it self otherwise it will wrap it with bad request error.
    res.status(err.status).json(BadRequestError.wrapIfNotWrapped(err)); 
});

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