Crate actix_state_guards
source ·Expand description
This crate provides a more flexible guard function for the [actix-web] framework.
The Guard acts as a gatekeeper for a specific scope and governs over which request is allowed to pass.
Guards can accept application state as well as types that implement the [FromReqeust] trait as parameters.
They can also execute asynchrones code inside them.
Example
#[derive(Debug)]
pub struct CounterError();
impl Display for CounterError {
fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
f.write_str("Error: Counter is over 100")
}
}
impl ResponseError for CounterError {}
#[get("/count")]
async fn count(counter: web::Data<Mutex<u32>>) -> impl Responder {
let mut counter = counter.lock().unwrap();
*counter += 1;
counter.to_string()
}
#[actix_web::main]
async fn main() -> Result<(), Box<dyn std::error::Error>> {
Ok(HttpServer::new(move || {
App::new()
.app_data(web::Data::new(Mutex::new(0u32)))
.use_state_guard(
|counter: web::Data<Mutex<u32>>| async move {
if *counter.lock().unwrap() < 100 {
Ok(())
} else {
// by returning the error case of the result enum we signal that this
// request shall not be allowed to pass on to the scope wrapped
Err(CounterError())
}
},
web::scope("").service(count),
)
})
.bind(("127.0.0.1", 8080))?
.run()
.await?)
}