[Rust] Don't use the `reqwest` crate when compiling to `wasm`

[bandogora]

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Ory Network Project

No response

Describe your problem

When compiling for a wasm target the reqwest crate shouldn't be used. We have access to the browser fetch api through the wasm-bindgen and web-sys crates.

Although reqwest does compile for wasm, it's overkill and doesn't yet support the setting the required CSRF cookies or the credentials: include fetch property.

Describe your ideal solution

Use the native browser fetch api through the wasm-bindgen and web-sys crates.

Example:

[dependencies]
gloo-utils = { version = "0.1", features = ["serde"] }
wasm-bindgen = "0.2.100"
wasm-bindgen-futures = "0.4.50"
web-sys = { version = "0.3.77", features = ["Headers", "Request", "RequestInit", "RequestMode", "Response", "Window", "RequestCredentials"] }

use gloo_utils::format::JsValueSerdeExt;
use wasm_bindgen::prelude::*;
use wasm_bindgen_futures::JsFuture;
use web_sys::{Request, RequestCredentials, RequestInit, RequestMode, Response};

pub async fn create_browser_registration_flow(
  kratos_browser_url: &str,
) -> Result<ory_kratos_client::models::RegistrationFlow, JsValue> {
  let opts = RequestInit::new();
  opts.set_method("GET");
  opts.set_mode(RequestMode::Cors);
  opts.set_credentials(RequestCredentials::Include);

  let url = format!("{}/self-service/registration/browser", kratos_browser_url);

  let request = Request::new_with_str_and_init(&url, &opts)?;

  request.headers().set("Accept", "application/json")?;

  let window = web_sys::window().unwrap();
  let resp_value = JsFuture::from(window.fetch_with_request(&request)).await?;

  // `resp_value` is a `Response` object.
  assert!(resp_value.is_instance_of::<Response>());
  let resp: Response = resp_value.dyn_into().unwrap();

  // Convert this other `Promise` into a rust `Future`.
  let json = JsFuture::from(resp.json()?).await?.into_serde().unwrap();
  Ok(json)
}

Workarounds or alternatives

The only work around I have found when trying to use the Rust SDK on the client side is rewriting the ory_kratos_client::apis::frontend_api functions to use wasm-bindgen.

Version

kratos-client-rust v1.3.8

Additional Context

No response

[bandogora]

I am not familiar with OpenAPI Generator, but I see that it doesn't officially support web-sys/wasm-bindgen as a rust library template.

Regardless, I've manually updated the kratos-client-rust to support target_family = "wasm".

It's not perfect but this fork could be used as a reference for someone who's able to update the OpenAPI Generator for the rust client.

This would allow people (like me) to create SPAs in rust.

ory/kratos-client-rust@master...justins-engineering:kratos-client-rust:master