From 7ae389f3b165a7b4f9b17ef96545f5430cfcd7bc Mon Sep 17 00:00:00 2001
From: metamuffin <metamuffin@disroot.org>
Date: Wed, 19 Mar 2025 00:22:01 +0100
Subject: delay module

---
 src/modules/delay.rs    | 47 +++++++++++++++++++++++++++++++++++++++++++++++
 src/modules/fallback.rs |  1 +
 src/modules/mod.rs      |  4 +++-
 3 files changed, 51 insertions(+), 1 deletion(-)
 create mode 100644 src/modules/delay.rs

(limited to 'src')

diff --git a/src/modules/delay.rs b/src/modules/delay.rs
new file mode 100644
index 0000000..ab46a90
--- /dev/null
+++ b/src/modules/delay.rs
@@ -0,0 +1,47 @@
+use super::{Node, NodeContext, NodeKind, NodeRequest, NodeResponse};
+use crate::{config::DynNode, error::ServiceError};
+use anyhow::Result;
+use rand_distr::Distribution;
+use serde::Deserialize;
+use serde_yml::Value;
+use std::{future::Future, pin::Pin, sync::Arc, time::Duration};
+use tokio::time::sleep;
+
+pub struct DelayKind;
+
+#[derive(Deserialize)]
+struct Delay {
+    duration: u64,
+    stdev: u64,
+    next: DynNode,
+}
+
+impl NodeKind for DelayKind {
+    fn name(&self) -> &'static str {
+        "delay"
+    }
+    fn instanciate(&self, config: Value) -> Result<Arc<dyn Node>> {
+        Ok(Arc::new(serde_yml::from_value::<Delay>(config)?))
+    }
+}
+impl Node for Delay {
+    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 {
+            sleep(Duration::from_millis(if self.stdev == 0 {
+                self.duration
+            } else {
+                self.duration.saturating_add_signed(
+                    rand_distr::Normal::new(0., self.stdev as f32)
+                        .unwrap()
+                        .sample(&mut rand::rng()) as i64,
+                )
+            }))
+            .await;
+            self.next.handle(context, request).await
+        })
+    }
+}
diff --git a/src/modules/fallback.rs b/src/modules/fallback.rs
index 6a5caaa..22ae1ef 100644
--- a/src/modules/fallback.rs
+++ b/src/modules/fallback.rs
@@ -20,6 +20,7 @@ impl NodeKind for FallbackKind {
         Ok(Arc::new(serde_yml::from_value::<Fallback>(config)?))
     }
 }
+
 impl Node for Fallback {
     fn handle<'a>(
         &'a self,
diff --git a/src/modules/mod.rs b/src/modules/mod.rs
index 283c86a..c9a7708 100644
--- a/src/modules/mod.rs
+++ b/src/modules/mod.rs
@@ -12,6 +12,7 @@ mod auth;
 mod cache;
 mod cgi;
 mod debug;
+mod delay;
 mod error;
 mod fallback;
 mod file;
@@ -19,13 +20,13 @@ mod files;
 mod headers;
 mod hosts;
 mod inspect;
+mod limits;
 mod loadbalance;
 mod paths;
 mod proxy;
 mod redirect;
 mod switch;
 mod upgrade_insecure;
-mod limits;
 
 pub type NodeRequest = Request<BoxBody<Bytes, ServiceError>>;
 pub type NodeResponse = Response<BoxBody<Bytes, ServiceError>>;
@@ -52,6 +53,7 @@ pub static MODULES: &[&dyn NodeKind] = &[
     &inspect::InspectKind,
     &fallback::FallbackKind,
     &limits::LimitsKind,
+    &delay::DelayKind,
 ];
 
 pub struct NodeContext {
-- 
cgit v1.2.3-70-g09d2