feat: add server config cache

.github/workflows/rust.yml

@@ -16,6 +16,10 @@ jobs:
 
     steps:
     - uses: actions/checkout@v3
+    - name: Set up Rust
+      uses: actions-rs/toolchain@v1
+      with:
+        toolchain: stable
     - name: Build
       run: cargo build --verbose
     - name: Run tests

Cargo.toml

@@ -34,6 +34,7 @@ tracing = "0.1.40"
 hyper-util = { version = "0.1.7", features = ["tokio"] }
 native-tls = { version = "0.2.12", features = ["alpn"] }
 thiserror = "1.0.62"
+dashmap = "6.0.1"
 
 [dev-dependencies]
 axum = { version = "0.7.2", features = ["http2"] }

rust-toolchain.toml

@@ -0,0 +1,2 @@
+[toolchain]
+channel = "stable"

src/tls.rs

@@ -1,9 +1,22 @@
+use std::{borrow::BorrowMut, sync::LazyLock};
+
+use dashmap::{try_result::TryResult, DashMap};
+use rustls::ServerConfig;
+
+static SERVER_CONFIG_CACHE: LazyLock<DashMap<(String, Vec<u8>), rustls::ServerConfig>> = LazyLock::new(|| DashMap::new());
+
 pub fn server_config(
     host: String,
     root_cert: &rcgen::CertifiedKey,
     h2: bool,
 ) -> Result<rustls::ServerConfig, rustls::Error> {
-    let mut cert_params = rcgen::CertificateParams::new(vec![host]).unwrap();
+
+    if let TryResult::Present(config) = SERVER_CONFIG_CACHE.try_get(&(host.clone(), root_cert.key_pair.serialize_der())) {
+        let mut config = config.clone();
+        return Ok(maybe_h2_config(&mut config, h2).to_owned());
+    }
+
+    let mut cert_params = rcgen::CertificateParams::new(vec![host.clone()]).unwrap();
     cert_params
         .key_usages
         .push(rcgen::KeyUsagePurpose::DigitalSignature);
@@ -29,11 +42,17 @@ pub fn server_config(
             )),
         );
 
+    if let Ok(config) = &config {
+        SERVER_CONFIG_CACHE.insert((host, root_cert.key_pair.serialize_der()), config.clone());
+    }
+
+    config.map(|mut config| maybe_h2_config(config.borrow_mut(), h2).to_owned())
+}
+
+fn maybe_h2_config(config: &mut ServerConfig, h2: bool) -> &ServerConfig {
     if h2 {
-        config.map(|mut server_config| {
-            server_config.alpn_protocols = vec!["h2".into(), "http/1.1".into()];
-            server_config
-        })
+        config.alpn_protocols = vec!["h2".into(), "http/1.1".into()];
+        config
     } else {
         config
     }