Configurable HTTP Methods for Bridge Carriers

Co-Authored-By: brekotis <93345790+brekotis@users.noreply.github.com>

src/config/hot_reload/carrier_method_tests.rs

@@ -0,0 +1,50 @@
+use super::*;
+
+use crate::config::WebCarrierMethod;
+
+#[test]
+fn carrier_method_reload_is_hot_and_preserves_process_limits() {
+    let mut active = ProxyConfig::default();
+    for method in [WebCarrierMethod::Put, WebCarrierMethod::Post] {
+        let mut desired = active.clone();
+        desired.web.carrier_method = method;
+        assert_eq!(classify_config_changes(&active, &desired).changed, ["web"]);
+        assert!(!classify_config_changes(&active, &desired).restart_required);
+        desired.web.limits.max_http_connections += 1;
+        let applied = overlay_hot_fields(&active, &desired);
+        assert_eq!(applied.web.carrier_method, method);
+        assert_eq!(
+            applied.web.limits.max_http_connections,
+            active.web.limits.max_http_connections
+        );
+        active = applied;
+    }
+}
+
+#[test]
+fn carrier_method_reload_publishes_both_directions_and_keeps_last_good_value() {
+    let directory = tempfile::tempdir().unwrap();
+    let path = directory.path().join("config.toml");
+    let source = |method| format!("[web]\ncarrier_method = \"{method}\"\n");
+    std::fs::write(&path, source("post")).unwrap();
+    let initial = Arc::new(ProxyConfig::load(&path).unwrap());
+    let initial_hash = ProxyConfig::load_with_metadata(&path)
+        .unwrap()
+        .rendered_hash;
+    let (config_tx, _config_rx) = watch::channel(Arc::clone(&initial));
+    let (log_tx, _log_rx) = watch::channel(initial.general.log_level.clone());
+    let mut reload_state = ReloadState::new(Some(initial_hash));
+    for (token, method) in [
+        ("put", WebCarrierMethod::Put),
+        ("post", WebCarrierMethod::Post),
+    ] {
+        std::fs::write(&path, source(token)).unwrap();
+        reload_config(&path, &config_tx, &log_tx, None, None, &mut reload_state).unwrap();
+        let applied = config_tx.borrow().clone();
+        assert_eq!(applied.web.carrier_method, method);
+        std::fs::write(&path, source("PATCH")).unwrap();
+        reload_config(&path, &config_tx, &log_tx, None, None, &mut reload_state);
+        let unchanged = config_tx.borrow().clone();
+        assert!(Arc::ptr_eq(&unchanged, &applied));
+    }
+}