use axum::body::{to_bytes, Body};
use axum::Router;
use bytes::Bytes;
use http::{request, response, Request, Response};
use std::path::PathBuf;
use std::sync::Arc;
use tauri::path::BaseDirectory;
use tauri::Manager;
use thiserror::Error;
use tokio::sync::{Mutex, MutexGuard};
use tower::{Service, ServiceExt};
#[derive(Error, Debug)]
pub enum DesktopError {
#[error("Axum error:\n{0}")]
Axum(#[from] axum::Error),
#[error("Infallible error")]
Infallible(#[from] std::convert::Infallible),
}
/// Process requests sent to Tauri (with the `axum://` protocol) and handle them with Axum
/// When an error occurs, this function is expected to panic, which should result in a 500 error
/// being sent to the client, so we let the client handle the error recovering
async fn process_tauri_request(
tauri_request: Request<Vec<u8>>,
mut router: MutexGuard<'_, Router>,
) -> Result<Response<Vec<u8>>, DesktopError> {
let (parts, body): (request::Parts, Vec<u8>) = tauri_request.into_parts();
let axum_request: Request<Body> = Request::from_parts(parts, body.into());
let axum_response: Response<Body> = router
.as_service()
.ready()
.await
.map_err(DesktopError::Infallible)?
.call(axum_request)
.await
.map_err(DesktopError::Infallible)?;
let (parts, body): (response::Parts, Body) = axum_response.into_parts();
let body: Bytes = to_bytes(body, usize::MAX).await?;
let tauri_response: Response<Vec<u8>> = Response::from_parts(parts, body.into());
Ok(tauri_response)
}
#[cfg_attr(mobile, tauri::mobile_entry_point)]
pub fn run() {
tauri::Builder::default()
.setup(|app| {
let assets_path: PathBuf = app
.path()
.resolve("assets", BaseDirectory::Resource)
.expect("Assets path should be resolvable");
// Adds Axum router to application state
// This makes it so we can retrieve it from any app instance (see bellow)
let router = Arc::new(Mutex::new(app::get_router(&assets_path)));
app.manage(router);
Ok(())
})
.register_asynchronous_uri_scheme_protocol("axum", move |app, request, responder| {
// Retrieve the router from the application state and clone it for the async block
let router = Arc::clone(&app.state::<Arc<Mutex<axum::Router>>>());
// Spawn a new async task to process the request
tauri::async_runtime::spawn(async move {
let router = router.lock().await;
match process_tauri_request(request, router).await {
Ok(response) => responder.respond(response),
Err(err) => {
let body = format!("Failed to process an axum:// request:\n{}", err);
responder.respond(
http::Response::builder()
.status(http::StatusCode::BAD_REQUEST)
.header(http::header::CONTENT_TYPE, "text/plain")
.body::<Vec<u8>>(body.into())
.expect("BAD_REQUEST response should be valid"),
)
}
}
});
})
.run(tauri::generate_context!())
.expect("error while running tauri application");
}