Workers Assets Binding

[BrandonDyer64]

closes #644

I went down a rabbit hole creating an entire new Assets env binding just to find out it's a Fetcher. In fact, you can use assets without this PR by just calling env.get_binding::<Fetcher>("ASSETS").

Testing:

• Run npx wrangler dev in worker-sandbox
• Go to /asset/test.txt
• See TEST in browser
• Go to /asset/doesnotexist.txt
• See 404

[BrandonDyer64]

Maybe this isn't enough. I'm doing some testing and setting the following in my wrangler.toml will serve the assets, but not expose the binding:

[assets]
binding = "ASSETS"
directory = "./public/"

I get something along the lines of

Your worker has access to the following bindings:
- D1 Databases:
  - DB: anaso (00000000-0000-0000-0000-000000000000)
- Vars:
  - ANASO_JWT_SECRET: "################"

Nothing related to assets.

I'm on wrangler 3.81.0, worker-build 0.1.0, and compatibility_date = "2024-09-19".

Edit: Resolved. The assets binding is working correctly, just not printing out.

[kflansburg]

Sorry that you went in circles on this. I think this looks correct. Have you tried deploying your worker and testing that? I will see if I can reproduce the issue in local development.

[kflansburg]

This worked locally for me. You do need to specify a dummy URL (I think all Fetchers behave this way).

[BrandonDyer64]

You do need to specify a dummy URL

Ah, that was it. Adding https://example.com to the beginning of my URL fixed it for me.

[BrandonDyer64]

Couple questions/feedback on this:

1. I don't see the ASSETS binding in the Your worker has access to the following bindings: printout. That seems like a bug, and it's why it took me so long to find a solution. I was chasing ghosts.
2. What's your recommendation for getting the fetch() response body as bytes? I had to import http_body_util::BodyExt and write this, just to get basic data out:

   • let bytes: Vec<u8> = response.into_body().collect().await?.to_bytes().to_vec();

[kflansburg]

Couple questions/feedback on this:

1. I don't see the ASSETS binding in the Your worker has access to the following bindings: printout. That seems like a bug, and it's why it took me so long to find a solution. I was chasing ghosts.

2. What's your recommendation for getting the fetch() response body as bytes? I had to import http_body_util::BodyExt and write this, just to get basic data out:

   • let bytes: Vec<u8> = response.into_body().collect().await?.to_bytes().to_vec();

I think 1. may be a bug in wrangler cc @petebacondarwin

For 2, I assume you are using the http crate feature? I think the main way to consume it is as a stream like you are doing, but I suppose we could add some utility methods to the concrete Body type you get from our Fetcher::fetch.

[BrandonDyer64]

we could add some utility methods to the concrete Body type you get from our Fetcher::fetch

I'd love to see an async fn to_bytes() -> Vec<u8> and async fn to_json<T>() -> T on Body if possible. It would make life a lot easier.

[BrandonDyer64]

I'm not sure why the tests are failing in the CI. Started happening after my first commit, which just added a single method to Env.

[BrandonDyer64]

Can anyone review this?

[kflansburg]

I'm no longer with Cloudflare, so I cannot approve. I think test failures are related to the Rust 1.82 issue here. We may need to pin the Rust version in our CI.

Otherwise, I think this is a good test to add. I would like to see it also tested with http flag enabled, we are trying to keep those two test suites identical and will probably eventually make http the default (or at least that was my original plan).

cc @harrishancock