Is there any reason I couldn't run a website in a durable object? - Cloudflare Developers

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johtso

J

johtsoOP•3/11/23, 1:22 PM

Would there be big performance issues?

johtso

Jjohtso Is there any reason I couldn't run a website in a durable object?

Hello, I’m Allie!

H

Hello, I’m Allie!•3/11/23, 1:27 PM

The biggest limitation is the limit of ~100 RPS

johtso

J

johtsoOP•3/11/23, 1:28 PM

Oh nice, that's plenty enough for me

johtso

J

johtsoOP•3/11/23, 1:28 PM

I guess you also need to make sure not to block the gates?

johtso

J

johtsoOP•3/11/23, 1:30 PM

For me one location is better, all requests are going to be from the same place

johtso

J

johtsoOP•3/11/23, 1:30 PM

And it means I can use kv without cache staleness issues

johtso

J

johtsoOP•3/11/23, 1:33 PM

Do you know of a nice DO based rate limiting example? I feel like there might have been a blog post..

johtso

J

johtsoOP•3/11/23, 1:58 PM

I guess it's not really a DO thing as it doesn't even need persistence

johtso

J

johtsoOP•3/11/23, 1:58 PM

just need a good in-memory rate limiter implementation

johtso

J

johtsoOP•3/11/23, 2:10 PM

I guess that's true as long as my rate limiting only cares about a window of 10 seconds or less

johtso

Jjohtso I guess that's true as long as my rate limiting only cares about a window of 10 ...

DaniFoldi

D

DaniFoldi•3/11/23, 2:12 PM

*30, DOs stick around for 30 seconds after a request

johtso

J

johtsoOP•3/11/23, 2:13 PM

good to know, I think the docs say a minimum of 10s

johtso

J

johtsoOP•3/11/23, 2:13 PM

"In the absence of failures, in-memory state should not be reset after less than 10 seconds of inactivity."

johtso

J

johtsoOP•3/11/23, 2:14 PM

but I guess that's the pessimistic number

johtso

J

johtsoOP•3/11/23, 2:15 PM

I wonder if it's better to implement a rate limiter as a proxy or just as an api that returns whether a request should be allowed..

johtso

J

johtsoOP•3/11/23, 2:15 PM

I guess a proxy would be more efficient

johtso

J

johtsoOP•3/11/23, 2:16 PM

but probably only very marginally?

johtso

J

johtsoOP•3/11/23, 2:25 PM

@skye_31 hold on a minute, if I hosted my website in a DO wouldn't everyone's requests block every time I made a fetch to another DO / worker?

johtso

J

johtsoOP•3/11/23, 2:25 PM

or is that input output gate stuff only for storage operations?

johtso

J

johtsoOP•3/11/23, 2:26 PM

which I guess I can turn off with allowConcurrencyallowConcurrency and allowUnconfirmedallowUnconfirmed

johtso

J

johtsoOP•3/11/23, 2:26 PM

no worries

johtso

Jjohtso @skye_31 hold on a minute, if I hosted my website in a DO wouldn't everyone's re...

DaniFoldi

D

DaniFoldi•3/11/23, 2:30 PM

You're correct in that if the input gate is closed, no new requests will come in. The input gate is opened whenever you make an external async request, such as fetch another DO/worker - so that should open the input gate and allow other requests to be processed in the meantime.

johtso

J

johtsoOP•3/11/23, 2:42 PM

just trying to get my head around what the deal is if every request needed to increment a value in storage, and making the get and then put atomic

johtso

J

johtsoOP•3/11/23, 2:44 PM

I feel like it just works, but I'd love to understand why

johtso

J

johtsoOP•3/11/23, 2:44 PM

I think I just need to read the blog post 10 more times until it all clicks

johtso

J

johtsoOP•3/11/23, 2:47 PM

and probably do some more reading on how javascript concurrency works

johtso

J

johtsoOP•3/11/23, 2:51 PM

"Any other events will be deferred until such a time as the object is no longer executing JavaScript code and is no longer waiting for any storage operations"

johtso

J

johtsoOP•3/11/23, 2:51 PM

I think this is the bit I was missing!

johtso

J

johtsoOP•3/11/23, 2:53 PM

new events wont be delivered while code is executing, only when the event loop is idle

johtso

J

johtsoOP•3/11/23, 3:03 PM

@skye_31 another potential issue. say my DO needed to calculate some expensive hashing function when a user logs in, that would block all other requests

johtso

J

johtsoOP•3/11/23, 3:03 PM

where as with a worker the other requests would get handled by another instance?

Original message was deleted

johtso

J

johtsoOP•3/11/23, 4:09 PM

so I guess you'd just have to be extra careful to have short execution time, and defer anything that might be cpu intensive to another worker/do

johtso

J

johtsoOP•3/11/23, 4:23 PM

@skye_31 I guess I just liked the idea that my entry point would be colocated with my other DOs so communicating between them would be faster, and things like a rate limit check could even be stored locally to avoid an extra request for each user request

johtso

J

johtsoOP•3/11/23, 4:24 PM

but yeah, premature optimisation

johtso

J

johtsoOP•3/11/23, 4:25 PM

yeah, it did seem like you could get pretty far with that!

Original message was deleted

johtso

J

johtsoOP•3/11/23, 4:28 PM

the one rule limit is kind of restrictive though

johtso

J

johtsoOP•3/11/23, 4:30 PM

probably enough though when I think about it

johtso

J

johtsoOP•3/11/23, 6:08 PM

can durable objects not have cron triggers?

DaniFoldi

D

DaniFoldi•3/11/23, 6:12 PM

They have something similar called alarms, which are actually more precise, but you have to schedule it every time

johtso

Jjohtso can durable objects not have cron triggers?

Hello, I’m Allie!

H

Hello, I’m Allie!•3/11/23, 6:12 PM

No, but they can have Alarms

Hello, I’m Allie!

HHello, I’m Allie!No, but they can have Alarms

DaniFoldi

D

DaniFoldi•3/11/23, 6:12 PM

ha, got you

DaniFoldi

DDaniFoldi ha, got you

Hello, I’m Allie!

H

Hello, I’m Allie!•3/11/23, 6:12 PM

Deletes your message so I’m first…

johtso

J

johtsoOP•3/11/23, 6:13 PM

yeah, just would be nice to have the simplicity of cron triggers you could twiddle in the dashboard

Hello, I’m Allie!

HHello, I’m Allie!*Deletes your message so I’m first…*

DaniFoldi

D

DaniFoldi•3/11/23, 6:13 PM

cries in non-colored dev expert

johtso

J

johtsoOP•3/11/23, 6:13 PM

curious if it's something that's planned

johtso

Jjohtso yeah, just would be nice to have the simplicity of cron triggers you could twidd...

Hello, I’m Allie!

H

Hello, I’m Allie!•3/11/23, 6:13 PM

I mean, you can pass Cron Triggers into a DO

johtso

Jjohtso curious if it's something that's planned

Hello, I’m Allie!

H

Hello, I’m Allie!•3/11/23, 6:14 PM

Probably not. You can pass them in if you need them, or otherwise build your own with Alarms

johtso

J

johtsoOP•3/11/23, 6:14 PM

get yer hands dirty

Hello, I’m Allie!

H

Hello, I’m Allie!•3/11/23, 6:14 PM

There’s not really much of a need that doesn’t work there

johtso

J

johtsoOP•3/11/23, 6:14 PM

I'm kind of surprised there aren't more abstractions built on top of DOs