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Comment by adam_arthur

3 years ago

I'm building an app with Cloudflare serverless and you can emulate everything locally with a single command and debug directly... It's pretty amazing.

But the way their offerings are structured means it will be quite expensive to run at scale without a multi cloud setup. You can't globally cache the results of a worker function in CDN, so any call to a semi dynamic endpoint incurs one paid invocation, and there's no mechanism to bypass this via CDN caching because the workers live in front of the CDN, not behind it.

Despite their media towards lowering cloud costs, they have explicitly designed their products to contain people in a cost structure similar to but different than via egress fees. And in fact it's quite easily bypassed by using a non Cloudflare CDN in front of Cloudflare serverless.

Anyway, I reached a similar conclusion that for my app a single large server instance works best. And actually I can fit my whole dataset in RAM, so disk/JSON storage and load on startup is even simpler than trying to use multiple systems and databases.

Further, can run this on a laptop for effectively free, and cache everything via CDN, rather than pay ~$100/month for a cloud instance.

When you're small, development time is going to be your biggest constraint, and I highly advocate all new projects start with a monolithic approach, though with a structure that's conducive to decoupling later.

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adam_arthur

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anonymousDan  3 years ago

As someone who has only dabbled with serverless (Azure functions), the difficulty in setting up a local dev environment was something I found really off-putting. There is no way I am hooking up my credit card to test something that is still in development. It just seems crazy to me. Glad to hear Cloudflare workers provides a better experience. Does it provide any support for mocking commonly used services?

  • adam_arthur  3 years ago

    Yes, you can run your entire serverless infrastructure locally with a single command and close to 0 config.

    It's far superior to other cloud offerings in that respect.

    You can even run it live in dev mode and remote debug the code. Check out miniflare/Wrangler v2

    Just wish they would have ability for persistent objects. Everything is still request driven, yet I want to schedule things on subminute schedules. You can do it today, but it requires hacks

julianbuse  3 years ago

I'm not sure if you know this, and it might not be useful to you even if you do, but workers can interact with the cache directly: https://developers.cloudflare.com/workers/runtime-apis/cache...

  • adam_arthur  3 years ago

    Yes, but the worker is in front of the cache (have to pay for an invocation even if cached), and the worker only interacts with the closest cache edge node, not the entire CDN.

    But yeah, there are a few hacky ways to work around things. You could have two different URLs and have the client check if the item is stale, if so, call the worker which updates it.

    I'm doing something similar with durable objects. I can get it to be persistent by having a cron that calls it every minute and then setting an alarm loop within the object.

    It's just super awkward. It feels like a design decision to drive monetization. Cloudflare would be perfect if they let you have a persistent durable object instance that could update global CDN content

    It's still the best serverless dev experience for me. Can do everything via JS while having transactional guarantees and globally distributed data right at the edge