Have you got the `packagePath: true` option set? - Cloudflare Developers

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MrBBot

MMrBBot Have you got the `packagePath: true` option set?

CalBoy

C

CalBoy•5/5/23, 8:29 AM

Yup and had a modulemodule set in package.json doing what was required for that above issue fixed it tho

ItHurtsWhenIPvp

I

ItHurtsWhenIPvp•5/13/23, 6:40 AM

Has anyone tried wrapping miniflare in their own package? Im looking to build a custom miniflare to interact with workers and our internal tooling. We're mostly wanting the local reproduction without giving the ability to publish themselves within the enterprise.

ItHurtsWhenIPvp

I

ItHurtsWhenIPvp•5/18/23, 8:25 AM

I may just be really tired today, but wasn't miniflare able to run typescript locally without a build step? May have been dreaming too.

sathoro

S

sathoro•5/18/23, 7:16 PM

I ran into another thing that miniflare does not fail on but real workers do fail:

const myBlob = await response.blob();

await env.BUCKET.put(blobId, myBlob); // must use myBlob.stream()

const myBlob = await response.blob();

await env.BUCKET.put(blobId, myBlob); // must use myBlob.stream()

sathoro

Ssathoro I ran into another thing that miniflare does not fail on but real workers do fai...

Adam

A

Adam•5/18/23, 7:22 PM

Can you file this in the Miniflare repo? https://github.com/cloudflare/miniflare/issues/new

Adam

AAdam Can you file this in the Miniflare repo? https://github.com/cloudflare/miniflare...

sathoro

S

sathoro•5/18/23, 7:25 PM

https://github.com/cloudflare/miniflare/issues/584 done

Rph

RRph Is it possible to somehow enable support for `eval` in miniflare?

MrBBot

M

MrBBotOP•5/24/23, 8:42 AM

Hey!

This isn't possible right now unfortunately. What's your use case?

Rph

RRph I wanted to build myself something akin to a hybrid between jupyter and codepen ...

MrBBot

M

MrBBotOP•5/24/23, 8:45 AM

Interesting... you might want to look into the Chrome DevTools protocol. Miniflare supports starting an inspector server, which you can then send WebSocket messages to for evaluating code in the Miniflare context.

Ben-xD

B

Ben-xD•5/27/23, 6:59 AM

Is wrangler3/miniflare3 planning to add support for breakpoints/debugging?

Unsmart

U

Unsmart•5/27/23, 7:38 PM

Seems to be there

https://github.com/cloudflare/miniflare/blob/6bace6b464e1458ac3621d14d639750455299853/packages/miniflare/src/api.ts#L111

GitHub

miniflare/api.ts at 6bace6b464e1458ac3621d14d639750455299853 · clou...

Fully-local simulator for Cloudflare Workers. Contribute to cloudflare/miniflare development by creating an account on GitHub.

miniflare/api.ts at 6bace6b464e1458ac3621d14d639750455299853 · clou...

Walshy

W

Walshy•5/27/23, 7:45 PM

in miniflare 3 it may have been removed/renamed

Walshy

W

Walshy•5/27/23, 7:45 PM

but I'd recommend just using Wrangler, Miniflare hasn't been the recommended way to do local development/testing for a few years now

ndls

Nndls i might just be daft, but doing local dev with cloudflare is not easy, and the d...

Adam

A

Adam•5/28/23, 9:21 PM

PM for Workers here

Thanks for the feedback. Updating and enhancing local documentation is in the works. Hopefully consolidating everything with Wrangler will reduce the need to figure out questions like - is this Miniflare or Wrangler. Sorry for the problems so far though. If I can help at all feel free to ping me directly.

Also, we are aware of the sveltekit issue and are talking through solutions there.

ernest

E

ernest•5/30/23, 6:16 AM

Openly thinking, are there an glaring reason why Miniflare would not be suitable for any production loads other than the fact that it's a watered down version/emulation/simulation of the full CF stack?

The novel use case I am envisioning is a hybrid-offline mode type of setup where we can fallback to a localised miniflare when outages happen?

Walshy

W

Walshy•5/30/23, 7:45 AM

The fact it's an emulation and not 100% true to prod

Though if Workers are down, so is a lot of CF these days haha so there'd be much bigger problems than just Workers not firing

You can run workerd which is the Workers runtime locally but again, I wouldn't worry about this scenario.

ernest

E

ernest•5/31/23, 7:04 AM

Less on workers/cf being down, but more localised problems like the ISP and power outages. Context is we're building some restaurant operation tools and was exploring using miniflare as a local/offline backend to work with in localhost until connectivity is restored

zegevlier

Z

zegevlier•5/31/23, 7:16 AM

Workerd will be a better bet in that case. It's designed to be ran locally

Hello, I’m Allie!

H

Hello, I’m Allie!•5/31/23, 8:00 AM

I would note too that

workerd

workerd

has some eccentricities from it being tailored to the CF platform, so while it works fine(mostly) for local dev, and you can use it for production loads, I would probably recommend adding a service-worker or equivalent to your tool code so that it can keep itself running, rather than trying to wrangler

workerd

workerd

into working locally.

Samy

S

Samy•6/1/23, 11:38 AM

Is miniflare still maintained as the recommended way to develop unit tests for workers?
We are working on adapting a work with durable objects to use the new WebSocket hibernation API, and it doesn't look like miniflare supports it, but mainly it looks like there is not much activity on the miniflare repo and no issue/PR about supporting this new API.

Samy

S

Samy•6/1/23, 11:39 AM

workerd seems to be the main way to run workers locally now, but it doesn't offer the same controls as miniflare (ex: trigger an alarm, access DO storage, restart the worker, etc).

Samy

SSamy workerd seems to be the main way to run workers locally now, but it doesn't offe...

Hello, I’m Allie!

H

Hello, I’m Allie!•6/1/23, 11:44 AM

There are three systems for developing/testing Workers locally:
workerd - the Workers Runtime
miniflare - provides Mocks and Compat stuff
wrangler - CLI and pixelcf

pixelcf

API interface.
All of these parts interoperate to produce a local development/testing environment
With the release of wrangler 3, everything should run through wrangler, rather than Miniflare directly.

Samy

S

Samy•6/1/23, 12:42 PM

Yes I'm getting that, but in my case it's more about the unit tests case, so using the JS API of Miniflare to run it and call different functions on it to inspect its state.
When running the worker for development, we use wrangler.

Samy

SSamy Yes I'm getting that, but in my case it's more about the unit tests case, so usi...

DaniFoldi

D

DaniFoldi•6/1/23, 12:56 PM

for the time being, i'd stick to your current setup (which I'm assuming is

vitest-environment-miniflare

vitest-environment-miniflare

, or maybe

jest-environment-miniflare

jest-environment-miniflare

), and there should be a new variant that supports v3 soontm

soontm

sathoro

S

sathoro•6/1/23, 5:45 PM

CacheError [ERR_DESERIALIZATION]: Unable to deserialize stored cached data due to missing metadata.
The cached data storage format changed in Miniflare 2. You cannot load cached data created with Miniflare 1 and must delete it.

CacheError [ERR_DESERIALIZATION]: Unable to deserialize stored cached data due to missing metadata.
The cached data storage format changed in Miniflare 2. You cannot load cached data created with Miniflare 1 and must delete it.

this just randomly happened for data that was just cached minutes before

Elliot Hesp

E

Elliot Hesp•6/2/23, 10:48 AM

Is there anyway to view KV records in a UI like the cloudflare dashboard?

Elliot Hesp

EElliot Hesp Is there anyway to view KV records in a UI like the cloudflare dashboard?

MrBBot

M

MrBBotOP•6/5/23, 11:25 AM

Not yet, but it is something I'd like to see us add. Probably going to explore IDE extensions for editting this data first though.

stevefrench

Sstevefrench is it possible to test workers with wrangler?

DaniFoldi

D

DaniFoldi•6/8/23, 2:20 PM

I'd stick to your current

vitest-environment-miniflare

vitest-environment-miniflare

setup until v3 supports it in some way - unit tests aren't currently possible - you can use

unstable_dev

unstable_dev

from wrangler if you want to do e2e

Eduardo

EEduardo are there any docs for v3? The current docs seems to be partially v2 and partial...

DaniFoldi

D

DaniFoldi•6/8/23, 9:51 PM

Currently, v3 is only meant to be used through wrangler dev, or unstable_dev - hopefully we’ll see updates to the vitest environment once all the blockers are resolved there. The team also mentioned IDE integrations so you can view/interact with the local bindings directly

CacheError [ERR_DESERIALIZATION]: Unable to deserialize stored cached data due to missing metadata.
The cached data storage format changed in Miniflare 2. You cannot load cached data created with Miniflare 1 and must delete it.

CacheError [ERR_DESERIALIZATION]: Unable to deserialize stored cached data due to missing metadata.
The cached data storage format changed in Miniflare 2. You cannot load cached data created with Miniflare 1 and must delete it.