Hate Try...Catch Error Handling in Node.js? Do This Instead

[@joelr8481]

I was just researching this yesterday. I like the idea of HOF, so I'll give it a test. For completeness, you might want to have shown how to manage granular error responses. There are some valid error responses that need to make it back to the user. For my project, I take advantage of throwing as quickly as possible on the first sign of an error, and using classes extended from Error that take an error code and payload. Once this error reaches the app.use for error handling, it sends the response itself. This way you can keep your app.use code very small, but still support complex error handling. Thanks for the HOF tip!

[@GravityJS]

Thanks, Joel! I usually will throw in a controller and pass a custom message, which then gets picked up by app.use and returned to the client (always trying to avoid passing the generated error).

[@arthurlewin1952]

How does it works behind the seen and there is one more doubt when I send the response code 500 it does not triggers the catch block of an async request

[@v0nnyboy]

Couldn't one just use the 'express-async-errors' library ? Just wondering !!

[@frosty129]

I think that's an even better solution, no?

[@AlTearjen]

thanks for explaining this, but I don't think you should be saying every error is a 500 error. It could be a bad request. I would suggest this code. res.status(err.status || 500); res.end();

[@mysteriousmsn]

Great Video, no try catch needed anymore, short and simple alternative.

[@leoMC4384]

Very useful. I'd add a fifth argument to the high order function: data about the operation, for logging in case of an error. Thank you. Great tutorial. 👏👏👏

[@GravityJS]

Thank you

[@RyanGosselin-xe9tl]

Do you have a code example of this suggestion? Im new to JS

[@joseph_oluwayomi]

You can instead create custom exception classes with message, status code and data. That way its cleaner.

[@flowerofash4439]

interesting how the fn function return it self as a promise and somehow it is connected to the express route

[@RyanGosselin-xe9tl]

Cool. Hope my bootcamp teacher approves haha

[@dav.R7]

@Gravity . I really liked your solution, it worked perfect here. But wouldn't it be better to write function as handler than use?

[@celebrate1989]

Subscribed.. Please continue to do more videos on Node. Thanks

[@kabapy2]

i am trying to implement this on a higher level, on the express router level, it works for non-async-routes, and fails for async routes . any insights ??

[@bonsayeb9620]

Hey, I'm facing the same issue, did you find out a solution?

[@npc73x]

What if I have a 4 middlewares and the error happened on 3 rd middleware ?

[@icheston]

The third middleware will still gets called 😂

[@sheldonfourie5959]

On your front-end like vue what do you recommend doing for your api? can you recommend any good docs on this or repos I can check out?

[@GravityJS]

To make the API calls? I use AXIOS.

[@sheldonfourie5959]

@@GravityJS how you handle your errors neatly on the front-end

[@galactusclb5733]

@@sheldonfourie5959 That's what I'm also looking for😊 ex : When using SQL, how to handle errors in the best way. like user input errors ( duplicate entries), coding errors. if (err) { if (err.code === 'ER_DUP_ENTRY') { throw new BaseError("Duplicate entry.....................", err, "sampleFunc"); }

[@germanoller4418]

really good work brother

[@icheston]

What about chaining different handlers, if the catch calls the next middleware and the next middleware is to handle email notification. Even if there is an error, the email will get send?

[@alexandryurkov9168]

Dude, this thing is awesome, thank u

[@GravityJS]

Glad you found it useful :)

[@roccodenicolo3921]

Thx for the video but I think in this way you just put all the different possible errors under '500+ general message'. Imagine we are developing a registration endpoint. maybe the problem could be that the user is trying to use a username that is used yet. In that case, the user will become back 500 'something went wrong' and he'll never understand how to fix the problem. is it my doubt right or I'm missing something in the workflow?

[@GravityJS]

Hey Rocco, the ‘something went wrong’ was just an example. You can throw an error with a custom message, like: throw { message: ‘You are already registered’ } and this will be caught and sent back to the user, so they will know exactly what problem is.

[@MatthewMcGuff]

IMO, when you are building an API you want quick responses success or failure. Having a global error handler like this ensure that no matter what happens your client quickly knows where there is a success or failure. Perhaps one could decided whether to log errors to API calls based upon environment variables. If dev you could send all errors to the client as this is very helpful in debugging an application. In prod these wouldn't show. Great video. This was exactly what I looking for.

[@sheldonfourie5959]

Also don't give the client to much info on what happened, always say the username or password you have entered is wrong as this is something attackers can use

[@mrtourist8066]

Thanks a lot for this informative and helpful video .😃

[@GravityJS]

Welcome :)

[@guillermosalguero3581]

Great video, keep up the great work!

[@GravityJS]

Thank you!

[@pratiik37]

Thanks for the video✨

[@ahmadkhudai]

bro this is so nice👍 this is going to save lives!

[@adventurer2395]

Great video! One drawback of this approach is that you lose complete control over creating contextual errors at different layers of your app, which improves debugging, because you’re never catching/handling them and just bubbling up anything that might happen.

[@GravityJS]

You can throw a specific error anywhere the catch it in this method. I messed up the video by passing a generic message back to the client and put a note in the description. Will do an updated video soon :)

[@angrysmilex]

Just throw new Error('This is new error') in if else statement in any function

[@dav.R7]

it was a good observation. I used the Joi library and I can't put the code status as 400.

[@kakam458]

You can still do independent try catch blocks if you need to. Also you can create custom error classes by inheriting the Error class. Then throw those instead. Like: class BadRequest extends Error{ constructor(message){ message = message || 'Unspecified Bad request'; super(message); this.status = 400; } } throw new BadRequest();

[@thevietphung6967]

Thank you so much your video helped me understand things that my lecturer didn't explain to me. Thanks again ❤

[@GravityJS]

You're welcome! :)

[@huaquanghuy3998]

Thanks you for awesome video

[@GravityJS]

You’re welcome :)

[@fakeplay4534]

Very good video!

[@abdirahmann]

i get your solution, its beautiful but how do i implement it for middlewares that need to execute a 'finally' after the try catch has ended. i need the finally part because for some middlewares i want to do a db transaction (i don't use ORMs), i use postgres and that involves checking out a client from the pool and the *finally* releasing it into pool after a transaction has completed. i'll give you an example: const client = await pool.connect() try { // very may queries are executed here res.status(201).json({message: "resource created successfully"}) } catch(err) { res.status(500).json({message: "something went wrong"}) } finally { // here is how i would like to be helped. Thanks :) client.release() } .... more code

[@aliadel1723]

bro sorry but can tell me how I can use it in any code and where in MVC??

[@krishnachandrasharma1321]

It’s helpful 👍

[@harshshah3797]

Video starts at 4:52

[@djmonteur]

many thanks

[@Ceghap]

why not use a middleware instead of HOF?

[@GravityJS]

Middleware is chained, it will execute after function.

[@prerakhere]

vid starts at 5:30

[@DR-ee4wv]

Man u r damn useful 🥰🥰🥰🥰

[@GravityJS]

Thank you :)

[@johnjiang4412]

unneccesory background music

[@mod7ex_fx]

great

[@dkruger9553]

You could also use a tryToCatch function like the one in this video: kzbin.info/www/bejne/l3K0n52ZrZqcq8k

[@sheldonfourie5959]

Good one!

[@mrtourist8066]

Subscribers++ 😁

[@edwinmunguia2049]

why are you complicating yourself? you just need to implement the error middleware and throw errors from controllers 🤷🏽

[@GravityJS]

That's exactly what I did in the video.

[@jabborsattarov4982]

👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍