WASM Support

[mpfaff]

I'd like to be able to decode the claims on my client in the browser (verification is not necessary).

Currently, using jsonwebtoken::decode with wasm32-unknown-unknown crashes in generated JavaScript with this error:

Uncaught TypeError: Error resolving module specifier “env”. Relative module specifiers must start with “./”, “../” or “/”.

[Keats]

That will mostly depend on whether ring supports wasm or not, I have no clue. The other dependencies should be ok?

[mpfaff]

I cloned the repository locally and made the changes necessary to use with wasm32-unknown-unknown. std::time::SystemTime::now() is also not currently supported for wasm32-unknown-unknown, so I used a cfg attribute to use Date.now on wasm32-unknown-unknown.

[mpfaff]

The other change I made was adding a no_verify feature flag that returns an error when Validation.validate_signature is true.

[Keats]

The other change I made was adding a no_verify feature flag that returns an error when Validation.validate_signature is true.

Why would you ever want that?

[mpfaff]

The other change I made was adding a no_verify feature flag that returns an error when Validation.validate_signature is true.

Why would you ever want that?

As I said, I just want to decode the claims on the client. There is no need for them to be verified on the client.

Once signature verification can be supported on WASM I intend to remove the feature from my fork.

[danielhuang]

Just decoding the claims can be done by decoding base64. Using this library is probably not necessary.

[oceanicsdotio]

Watching this for server-side Node target.

[SylvainGarrigues]

I cloned the repository locally and made the changes necessary to use with wasm32-unknown-unknown. std::time::SystemTime::now() is also not currently supported for wasm32-unknown-unknown, so I used a cfg attribute to use Date.now on wasm32-unknown-unknown.

I am also stuck on this issue, and therefore I cannot use this crate with Cloudflare workers in Rust @mpfaff what were the necessary changes?

[mpfaff]

Just decoding the claims can be done by decoding base64. Using this library is probably not necessary.

That's ignoring the point which is that I want to be able to use the same library on the server and the client.

[mikeumus]

@mpfaff +1 with @SylvainGarrigues on hoping to see a fork of yours that works with WASM <3

@SylvainGarrigues same thing for me. I wrote a bunch of Worker endpoints that all validate with jsonwebtoken with a bunch of tests and then finally tested it and got that weird env module error 😕

[mpfaff]

Hey @SylvainGarrigues and @mikeumus. Feel free to view my changes over at https://git.pfaff.dev/michael/jsonwebtoken/commits/branch/master. My fork uses a little library I made that provides a now_utc function that uses js_sys::Date::now when target_arch = "wasm32" and simply wraps time::OffsetDateTime::now_utc on other architectures.

[Keats]

Isn't that what time does already? https://github.com/time-rs/time/blob/916004f5e3aef2f249d57ba828550be55ed7aaf3/time/src/date_time.rs#L307 Granted you can skip time entirely and just have the function in jsonwebtoken to avoid a dependency.

[mpfaff]

Isn't that what time does already? https://github.com/time-rs/time/blob/916004f5e3aef2f249d57ba828550be55ed7aaf3/time/src/date_time.rs#L307 Granted you can skip time entirely and just have the function in jsonwebtoken to avoid a dependency.

It's been a while, so my memory on this isn't clear, but I believe that at the time I first implemented that the time crate did not yet support wasm. It does look like it could now be used directly instead.

[Keats]

We have wasm tests in CI now and it seems to pass?

[jyrihogman]

Any news on this? Target wasm32-unknown-unknown at least fails due to ring.

Build command: cargo install -q worker-build && worker-build --release

The following warnings were emitted during compilation:

warning: ring@0.17.8: error: unable to create target: 'No available targets are compatible with triple "wasm32-unknown-unknown"'
warning: ring@0.17.8: 1 error generated.

error: failed to run custom build command for `ring v0.17.8`

Caused by:
  process didn't exit successfully: `/Users/jyri.hogman/personal/serverless-rust-example/target/release/build/ring-90bafb4544c99db7/build-script-build` (exit status: 1)
  --- stdout
  cargo:rerun-if-env-changed=RING_PREGENERATE_ASM
  cargo:rustc-env=RING_CORE_PREFIX=ring_core_0_17_8_
  OPT_LEVEL = Some("3")
  TARGET = Some("wasm32-unknown-unknown")
  HOST = Some("x86_64-apple-darwin")
  cargo:rerun-if-env-changed=CC_wasm32-unknown-unknown
  CC_wasm32-unknown-unknown = None
  cargo:rerun-if-env-changed=CC_wasm32_unknown_unknown
  CC_wasm32_unknown_unknown = None
  cargo:rerun-if-env-changed=TARGET_CC
  TARGET_CC = None
  cargo:rerun-if-env-changed=CC
  CC = None
  cargo:rerun-if-env-changed=CRATE_CC_NO_DEFAULTS
  CRATE_CC_NO_DEFAULTS = None
  DEBUG = Some("false")
  cargo:rerun-if-env-changed=CFLAGS_wasm32-unknown-unknown
  CFLAGS_wasm32-unknown-unknown = None
  cargo:rerun-if-env-changed=CFLAGS_wasm32_unknown_unknown
  CFLAGS_wasm32_unknown_unknown = None
  cargo:rerun-if-env-changed=TARGET_CFLAGS
  TARGET_CFLAGS = None
  cargo:rerun-if-env-changed=CFLAGS
  CFLAGS = None
  cargo:warning=error: unable to create target: 'No available targets are compatible with triple "wasm32-unknown-unknown"'
  cargo:warning=1 error generated.

  --- stderr

[Keats]

We do run tests in wasm (https://github.com/Keats/jsonwebtoken/blob/master/.github/workflows/ci.yml#L63). Other than that i don't know what else is missing

[danny900714]

If you are using macOS arm64, follow the instructions shown in this ring issue: https://github.com/briansmith/ring/issues/1824#issuecomment-2059955073