Hard-won lessons: Five years with Node.js
blog.scottnonnenberg.com
Hard-won lessons: Five years with Node.js
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Re: Hard-won lessons: Five years with Node.js
#2The biggest hard lessons I've had with Node.js have been around handling errors - when I first deployed https://www.findlectures.com, I was shocked to realize that uncaught errors could take down the whole site. Not handling error callbacks is also a big problem - TypeScript has been an awesome solution though, because it can show compilation errors if you screw up function arguments.
Re: Hard-won lessons: Five years with Node.js
#3Something I found surprising was the 1.5 GB limit per process when used on Heroku (https://devcenter.heroku.com/articles/node-concurrency), which afaik can be circumvented elsewhere (https://futurestud.io/tutorials/node-js-increase-the-memory-...).
This can be problematic at times if you need to open a very large number of concurrent connections (crawlers, slack connections etc), and can force you to organize a "cluster" of processes before you really want it.
Re: Hard-won lessons: Five years with Node.js
#4The biggest hard lessons I've had with Node.js have been around handling errors - when I first deployed https://www.findlectures.com , I was shocked to realize that uncaught errors could take down the whole site. Not handling error callbacks is also a big problem - TypeScript has been an awesome solution though, because it can show compilation errors if you screw up function arguments.
That's not Node.js. That's Express or a similar abstraction.
You can execute everything inside a promise like with Koa, which amounts to something like:
http.createServer((req, res) => {
handle(req)
.then((response) => res.send(response))
.catch(() => res.send(500))
})
Re: Hard-won lessons: Five years with Node.js
#5The biggest hard lessons I've had with Node.js have been around handling errors - when I first deployed https://www.findlectures.com , I was shocked to realize that uncaught errors could take down the whole site. Not handling error callbacks is also a big problem - TypeScript has been an awesome solution though, because it can show compilation errors if you screw up function arguments.
That's not Node.js. That's Express or a similar abstraction. You can execute everything inside a promise like with Koa, which amounts to something like: http.createServer((req, res) => { handle(req) .then((response) => res.send(response)) .catch(() => res.send(500)) }) Where `handle` is an async function and thus all your application logic is in async/await space.
But you're still error handling with `.catch()`. Without that, you'd have an uncaught Promise rejection, which could take down your Node process.
Re: Hard-won lessons: Five years with Node.js
#6These read almost like Zen koans. Such good stuff.
Re: Hard-won lessons: Five years with Node.js
#7Earlier quoted context omitted.
That's not Node.js. That's Express or a similar abstraction. You can execute everything inside a promise like with Koa, which amounts to something like: http.createServer((req, res) => { handle(req) .then((response) => res.send(response)) .catch(() => res.send(500)) }) Where `handle` is an async function and thus all your application logic is in async/await space.
But you're still error handling with `.catch()`. Without that, you'd have an uncaught Promise rejection, which could take down your Node process.
It's common for people to complain about something like a syntax error taking down their whole process, so that's how I read it -- that you're trying to do "too much" catching.
Re: Hard-won lessons: Five years with Node.js
#8These read almost like Zen koans. Such good stuff.
I agree. I wouldn't quite call it koan-level but the breezy style is definitely attractive to me.
Re: Hard-won lessons: Five years with Node.js
#9Earlier quoted context omitted.
But you're still error handling with `.catch()`. Without that, you'd have an uncaught Promise rejection, which could take down your Node process.
It's common for people to complain about something like a syntax error taking down their whole process, so that's how I read it -- that you're trying to do "too much" catching.
I'm not an expert with deploying application servers but shouldn't part of handling lifecycle include the ability for a service to crash and be respawned?
Ie. Be okay if a syntax error crashes your server.
Re: Hard-won lessons: Five years with Node.js
#10Earlier quoted context omitted.
It's common for people to complain about something like a syntax error taking down their whole process, so that's how I read it -- that you're trying to do "too much" catching.
I'm not an expert with deploying application servers but shouldn't part of handling lifecycle include the ability for a service to crash and be respawned? Ie. Be okay if a syntax error crashes your server.
Yes you should be using a process manager like PM2.