express_centralized_error_handler

A simple module for handling errors in express it contain three functions ErrorHandlerClass, errorHandlerMiddleware and asyncErrorHandler.

Example

const express = require('express');
const {ErrorHandlerClass,errorHandlerMiddleware,asyncErrorHandler} = require('express_centralized_error_handler')

const app = express()

// async error handler 
app.get('/',asyncErrorHandler(async(req,res,next)=>{
    const user = undefined;
    //customize error message with code
    if(!user){
        return next(new ErrorHandlerClass('User not found',404))
    }
}))

//sync error handler
app.get('/user', (req, res, next) => {
    //This will give error message user not found
    res.send(user);
})

//default error handler
app.get('/defaulterror', (req, res, next) => {
    //This will give default error message 'Something went wrong' with status code 500
    next(new ErrorHandlerClass());
})


// error middleware
app.use(errorHandlerMiddleware)

app.lister(port,()=>{
    console.log('server listening on port')
})

1. errorHandlerMiddleware :- errorHandlerMiddleware is middleware for error handling you have to provide this middleware in your main file as app.use(errorHandlerMiddleware). Always use this line after all the defined routes neither it will not work as expected.

2.ErrorHandlerClass :- ErrorHandlerClass is a class that can help to customize the error message and error port accordingly usage of this class is next(new ErrorHandlerClass("error messsage",statuscode)).

3.asyncErrorHandler :- asyncErrorHandler is a function which handle async error handling using this function you can write async functions without try..catch block for that you have to wrap your callback function into asyncErrorHandler.