kvarn

Macro prepare

source
macro_rules! prepare {
    ($request:pat, $host:pat, $path:pat, $addr:pat, $(move |$($move:ident:$ty:ty),+|)? $code:block) => { ... };
}
Expand description

Construct a Prepare extension like you write closures.

See super::PrepareCall for a list of arguments.

The path will be None if and only if crate::host::Options::disable_fs is true or percent decoding failed. request.uri().path() will not have it’s percent encoding decoded.

See example below. Where times_called is defined in the arguments of the macro, you can enter several Arcs to capture from the environment. They will be cloned before being moved to the future, mitigating the error cannot move out of 'times_called', a captured variable in an 'Fn' closure. Only Arcs will work, since the variable has to be Send and Sync.

You have to have kvarn imported as kvarn.

§Examples

These examples are applicable to all other extension-creation macros, but with different parameters. See their respective documentation.

use std::sync::{Arc, atomic};

let times_called = Arc::new(atomic::AtomicUsize::new(0));

prepare!(req, host, _path, _, move |times_called: Arc<atomic::AtomicUsize>| {
    let times_called = times_called.fetch_add(1, atomic::Ordering::Relaxed);
    println!("Called {} time(s). Request {:?}", times_called, req);

    default_error_response(StatusCode::NOT_FOUND, host, None).await
});

To capture no variables, just leave out the move ||.

prepare!(_request, host, _, _addr, {
    default_error_response(StatusCode::METHOD_NOT_ALLOWED, host, None).await
});