Kchat: Persistent group chat in <50 lines using kdb+/k/q web sockets, JavaScript

https://github.com/srpeck/kchat

by telotortium • 3 years ago

155 93 3 years ago

github.com

1vuio0pswjnm73• 3 years ago

Why use Javascript?

revskill• 3 years ago

It's fast.

tcfhgj2• 3 years ago

Not really

kindawinda• 3 years ago

Why ask a question that will spawn a comment thread about language superiority without testing or acknowledge what the author provided?

Setup stress testing and worked flawlessly. Impressive work author.

croes• 3 years ago

Critique or honest question?

For the former, because the developer wanted to use Javascript.

Sosh101• 3 years ago

Why use anything?

vidarh3• 3 years ago

On the server? As an example of equivalent (to the k and q versions) code.

On the client? Because endlessly refreshing the page to refresh chat messages is an awful design that we had enough of already in the 90's.

HotGarbage2• 3 years ago

Could be done with long polling or a never-closing HTTP response.

POST to an iframe to keep the page from reloading on send.

holoduke• 3 years ago

Because its the most convenient language on the client there is.

1vuio0pswjnm73• 3 years ago

This submission would not have made the front page unless I jump started some discussion. Mine was the first comment. It worked. Front page.

Years ago I had used k-based chat, with GUI, on Windows. Without Javascript. (Many years ago, k used to have a built-in GUI.)

"Why use Javascript" was a genuine question.

BozeWolf• 3 years ago

Fun! Combine it with ios notifications for web apps and rename the title of this post to “<60 lines”.

https://developer.apple.com/documentation/usernotifications/...

HotGarbage2• 3 years ago

It's sadly more than 10 lines, server and client side.

https://peter.hotgarba.ge

asim• 3 years ago

Something about the simplicity of the UI is so refreshing. Thanks for sharing.

toastal7• 3 years ago

This reminds me that XMPP needs to make a comeback. Its push-oriented nature is efficient, was largely built in a time when we didn’t expect users to have unlimited data, and the eXtensible part has allowed it to modernize with multi-device encryption, loading chat history, etc.

srgpqt• 3 years ago

Matrix is arguably the modern successor to XMPP.

Jiejeing• 3 years ago

It is a bit weird to frame one of two competing protocols as the successor of the other, when the only data point for this assertion is that one is older.

f1refly• 3 years ago

Matrix is not even close to the lightweight nature of xmpp.

huttt• 3 years ago

XMPP hasn't gone away, it's incredibly popular: WhatsApp is built upon it, with over a billion users.

ilyt2• 3 years ago

can you federate with whatsapp ? No? Then it doesn't matter

talhah2• 3 years ago

XMPP would be viable if it had a better iOS client. Some of my contacts switched to iOS and every app we tried wasn't as good as "Conversations" on Android.

toastal7• 3 years ago

Is Monal not good? I don’t know since I don’t use or recommend Apple devices, but I saw they were putting in GSoC bids for features.

lmm2• 3 years ago

XMPP needs to die and stay dead. Its extensible design ended up being flexible in all the wrong ways, at once horrendously complex to implement and yet impossible to make do the right thing in several key areas.

MattJ1003• 3 years ago

You could make similar arguments against just about any mature network protocol (see the recent HN post about regrets in TCP/IP's design). Luckily we have plenty of choice, and there are bridges between the open solutions.

The fact is that XMPP has been, and still is, happily deployed at scale in various scenarios. You're welcome to your opinions, but they are just that.

Disclaimer: I'm a full-time XMPP developer and executive director of the XMPP Standards Foundation.

ddoolin2• 3 years ago

I forget about k/q every time until it shows up here. It seems like something fun to learn but that I'd have no practical use for personally.

leprechaun10662• 3 years ago

https://spacetraders.io/ is API based. Considering that q is used for trading and analysis in the real world seems like it's a good way to go on an adventure.

ddoolin2• 3 years ago

This is pretty cool, thanks for sharing.

huhtenberg• 3 years ago

Pfft, chat.k is still just way too verbose compared to the good old

   # cat > a.out

nivertech2• 3 years ago

Each chat participant opens 2 bash terminals:

Terminal #1

  $ touch chat.txt

  $ tail -f chat.txt
  # or
  $ watch chat.txt

Terminal #2

  $ echo "${USER}: hello" >> chat.txt
  $ echo "${USER}: hello, again" >> chat.txt
  $ echo "${USER}: bye!" >> chat.txt

Also there are builtin UNIX/Linux CLI commands to send messages to users.

Kiro• 3 years ago

What is kdb+/k/q? The link to kx.com didn't tell me much.

jpfr• 3 years ago

k and q are array languages in the APL tradition. APL is one the "ur programming languges". https://madhadron.com/programming/seven_ur_languages.html

Here's an open source implementation of k: https://codeberg.org/ngn/k/

kdb is a time-series database with deep integration to k. It is famously used in the financial industry.

duskwuff• 3 years ago

It's a somewhat esoteric, and extremely terse, language used by some financial modeling firms. Influenced heavily by APL, but (thankfully!) without the non-ASCII characters.

https://en.wikipedia.org/wiki/K_(programming_language)

curiousgal• 3 years ago

It's also used by every investment bank who's active in the algo/e-trading business.

LukaD• 3 years ago

Came here to ask the same. kx.com is just some marketing page. I still have no idea what kdb+/k/q is.

ssfrr2• 3 years ago

k: super terse language inspired by APL and lisp

q: slightly less-terse language written in k, with similar semantics. The vendor (kx) supports q, not k

kdb+: column-oriented database bundled with q

steveBK1233• 3 years ago

Skip all the marketing materials & go to the dev pages - https://code.kx.com/q/learn/install/

samwillis2• 3 years ago

Previous thread from 2015: https://news.ycombinator.com/item?id=9120246

swyx• 3 years ago

a more scalable and readable version of this today would prolly use something like a partykit.io

Avshalom2• 3 years ago

N.B. https://code.kx.com/q/ref/dotz/ is doing the heavy lifting here.

bshimmin• 3 years ago

This is such a helpful comment - what looks, to the uninitiated, like line noise actually starts to make some sense now!

Paul-Craft2• 3 years ago

Lol, yes! That language looks like it was optimized for code golfing or something.

Paul-Craft2• 3 years ago

Pay no attention to that man behind the curtain!

Lol. Seriously though, that's how all of these kinds of $DO_SOPHISTICATED_THING in $ABSURDLY_FEW lines goes.

ssfrr2• 3 years ago

Your comment makes it sound like they’re using some task-specific library, but this looks like pretty generic standard library functions to me.

foul• 3 years ago

Such an incredible stack.

brenns10• 3 years ago

As an alternative to web sockets and JavaScript, can I offer my alternative (ok, it's not persistent chat) implemented with character devices as a Linux kernel module? I don't know if it still works, but it has the same name :)

https://github.com/brenns10/kchat

austinjp• 3 years ago

Strange set of comments in this thread.

Personally, I'd not heard of k or kdb before so this was an interesting read.

The code is from 9 years ago, and looks to me like a proof of concept. It's a kinda stepping stone between the 90s approaches * mentioned in sibling comments and the bloat of the modern web.

* A truly amazing and dreadful time. The commercial (and artistic/indie) web pushed developers to twist immature technologies and create perverse superpowers. Never-closing responses in hidden iframes. Constantly exploiting JS engine bugs as features. Disgusting fun.

paulgb• 3 years ago

This is a fun code golf challenge. 42 lines of JS with DriftDB[1]: https://codesandbox.io/s/distracted-wildflower-3jhtjq?file=/...

Each time it opens generates a new room, but you can copy/paste the URL of that room to access the same room (for up to 24 hours)

[1] https://github.com/drifting-in-space/driftdb

mianos2• 3 years ago

All good except the 50K a year license to run 'q'.

plagiarist• 3 years ago

Oh, yikes. I was interested in following up reading about kdb and now I am not.

steveBK1233• 3 years ago

cost is for commercial license only

free for personal use for 12 months, then you click some buttons to renew another 12 months, etc https://kx.com/kdb-personal-edition-download/

shin_lao• 3 years ago

Per core

leprechaun10662• 3 years ago

Azure has prices that vary:

https://azuremarketplace.microsoft.com/en-us/marketplace/app...

That's for commercial though.

One can get a personal use license for hobbies as other commenters have pointed out.

steveBK1233• 3 years ago

People paying $MM/year for SaaS that does less, but have prettier websites

mianos2• 3 years ago

No doubt, kdb/q is offers a of bang for buck in a commercial scenario. We use it and for some stuff it's good value, aside from staffing costs.

prettyStandard2• 3 years ago

Is there a difference between .htm and .html? I never thought so, and noticing they chose .htm reenforces my belief.

prettyStandard2• 3 years ago

For the most part the same, but .htm hails from win 3.x days because of 3 character file extension limitations, while *nix did not.

https://stackoverflow.com/a/138957

whalesalad2• 3 years ago

wow throwback chrome ui on windows 7 bringing a nice wave of nostalgia this morning

Kchat: Persistent group chat in <50 lines using kdb+/k/q web sockets, JavaScript

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