1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
|
/*
This file is part of gnix (https://codeberg.org/metamuffin/gnix)
which is licensed under the GNU Affero General Public License (version 3); see /COPYING.
Copyright (C) 2025 metamuffin <metamuffin.org>
*/
use super::{Node, NodeContext, NodeKind, NodeRequest, NodeResponse};
use crate::{config::DynNode, error::ServiceError};
use anyhow::Result;
use serde::Deserialize;
use serde_yml::Value;
use std::{future::Future, pin::Pin, sync::Arc};
use tokio::sync::Semaphore;
pub struct SemaphoreKind;
#[derive(Deserialize)]
struct SemaphoreConfig {
permits: usize,
next: DynNode,
}
struct SemaphoreState {
config: SemaphoreConfig,
semaphore: Semaphore,
}
impl NodeKind for SemaphoreKind {
fn name(&self) -> &'static str {
"semaphore"
}
fn instanciate(&self, config: Value) -> Result<Arc<dyn Node>> {
let config = serde_yml::from_value::<SemaphoreConfig>(config)?;
Ok(Arc::new(SemaphoreState {
semaphore: Semaphore::new(config.permits),
config,
}))
}
}
impl Node for SemaphoreState {
fn handle<'a>(
&'a self,
context: &'a mut NodeContext,
request: NodeRequest,
) -> Pin<Box<dyn Future<Output = Result<NodeResponse, ServiceError>> + Send + Sync + 'a>> {
Box::pin(async move {
let _permit = self.semaphore.acquire().await;
let resp = self.config.next.handle(context, request).await?;
drop(_permit);
Ok(resp)
})
}
}
|
