feat(admin): restore config admin compatibility (#3133)

* feat(admin): restore config admin compatibility

Co-authored-by: weisd <im@weisd.in>

* fix(admin): align config admin clean rebuild

Co-authored-by: weisd <im@weisd.in>

* fix(admin): align config history and peer signals

* fix(admin): harden config admin mutations

* fix(admin): tighten config review follow-ups

* perf(admin): reuse env snapshot in config render

* fix(ecstore): clean up config admin and listing error handling

Remove redundant is_all_volume_not_found check in list_merged, add
storage class encode/decode roundtrip tests, fresh boot integration
test, and config admin clean rebuild improvements.

Co-authored-by: hehutu <heihutu@gmail.com>

* fix(admin): sync global server config on mutation and reload

Change GLOBAL_SERVER_CONFIG from OnceLock to RwLock so config mutations
(set/del/restore/reload) are visible to readers without restart. Call
set_global_server_config after every store save and on snapshot reload.
Register storage_class as a dynamic config subsystem.

Co-authored-by: hehutu <heihutu@gmail.com>

* style: apply rustfmt to config and admin tests

Co-authored-by: hehutu <heihutu@gmail.com>

* fix(test): update signal_service test for storage_class dynamic subsystem

storage_class is now a valid dynamic config subsystem, so the
"requires object layer" test should expect "storage layer not initialized"
instead of "unsupported dynamic config subsystem".

Co-authored-by: hehutu <heihutu@gmail.com>

* fix(config): publish storage_class runtime config on dynamic reload

Change GLOBAL_STORAGE_CLASS from OnceLock to RwLock so runtime updates
are possible. apply_storage_class_runtime_config now actually publishes
the parsed config via set_global_storage_class instead of dropping it.

Addresses review feedback: storage_class was marked as dynamically
applied but the parsed result was discarded, so mc admin config set
returned config_applied=true while the runtime kept using stale parity
settings until restart.

Co-authored-by: hehutu <heihutu@gmail.com>

* fix(admin): harden config init, history ordering, and env redaction

- Change GLOBAL_SERVER_CONFIG from RwLock<Config> to RwLock<Option<Config>>
  initialized with None, preserving "not initialized" detection via None
- Move save_server_config_history before save_server_config_to_store in
  SetConfigKVHandler, DelConfigKVHandler, and SetConfigHandler so a
  restore point exists before mutations are persisted
- Redact sensitive env override values with *redacted* instead of
  silently omitting the line, improving admin visibility
- Add code comment explaining VolumeNotFound removal rationale in
  list_merged for listing paths

Co-authored-by: hehutu <heihutu@gmail.com>

* fix(config): keep in-memory config in sync after set/restore/reload

GLOBAL_SERVER_CONFIG was a OnceLock set once at startup and never
updated. After mc admin config set writes to the store, any fallback
to get_global_server_config() returned stale init-time data. Similarly,
reload_runtime_config_snapshot read from the store but discarded the
result.

- Replace OnceLock with RwLock for GLOBAL_SERVER_CONFIG and
  GLOBAL_STORAGE_CLASS so they can be updated at runtime
- Add set_global_server_config / set_global_storage_class setters
- Call set_global_server_config after every config save (set-kv,
  del-kv, set-config, restore-history)
- Re-apply dynamic subsystems (storage_class, audit_webhook,
  audit_mqtt) and signal peers in reload_runtime_config_snapshot
  and full-config operations
- Fix render_selected_config scope boundary check: track per-scope
  line count instead of checking global lines.is_empty()
- Include STORAGE_CLASS_SUB_SYS in is_dynamic_config_subsystem so
  apply_storage_class_runtime_config is reachable

Co-authored-by: hehutu <heihutu@gmail.com>

* fix(storageclass): use CLASS_RRS key in lookup_config for RRS parity

lookup_config used kvs.get(RRS) where RRS="REDUCED_REDUNDANCY", but the
admin config path writes the key as CLASS_RRS="rrs". This caused RRS
values to never be read back, always falling back to default parity.

- Changed kvs.get(RRS) to kvs.get(CLASS_RRS) in lookup_config
- Added regression tests verifying RRS read/write consistency

Co-authored-by: hehutu <heihutu@gmail.com>

* fix(config): add peer-side logging and don't swallow apply errors

- Add tracing::warn! in reload_dynamic_config_runtime_state and
  reload_runtime_config_snapshot when config read or subsystem apply
  fails, so on-host diagnostics show which signal failed and why
- Change `let _ = apply_dynamic_config_for_subsystem(...)` to
  `if let Err(err) = ... { warn!(...) }` in reload_runtime_config_snapshot
  so per-subsystem failures are logged instead of silently swallowed
- Remove weak test global_server_config_returns_none_before_init that
  had no meaningful assertion due to shared global state

Co-authored-by: hehutu <heihutu@gmail.com>

* style: apply rustfmt to config and storageclass tests

Co-authored-by: hehutu <heihutu@gmail.com>

---------

Co-authored-by: weisd <im@weisd.in>
Co-authored-by: hehutu <heihutu@gmail.com>

crates/ecstore/src/config/mod.rs

@@ -37,11 +37,12 @@ use rustfs_config::oidc::IDENTITY_OPENID_SUB_SYS;
 use serde::{Deserialize, Serialize};
 use std::collections::HashMap;
 use std::sync::LazyLock;
-use std::sync::{Arc, OnceLock};
+use std::sync::{Arc, OnceLock, RwLock};
 
-pub static GLOBAL_STORAGE_CLASS: LazyLock<OnceLock<storageclass::Config>> = LazyLock::new(OnceLock::new);
+pub static GLOBAL_STORAGE_CLASS: LazyLock<RwLock<storageclass::Config>> =
+    LazyLock::new(|| RwLock::new(storageclass::Config::default()));
 pub static DEFAULT_KVS: LazyLock<OnceLock<HashMap<String, KVS>>> = LazyLock::new(OnceLock::new);
-pub static GLOBAL_SERVER_CONFIG: LazyLock<OnceLock<Config>> = LazyLock::new(OnceLock::new);
+pub static GLOBAL_SERVER_CONFIG: LazyLock<RwLock<Option<Config>>> = LazyLock::new(|| RwLock::new(None));
 pub static GLOBAL_CONFIG_SYS: LazyLock<ConfigSys> = LazyLock::new(ConfigSys::new);
 
 pub static RUSTFS_CONFIG_PREFIX: &str = "config";
@@ -63,14 +64,30 @@ impl ConfigSys {
 
         lookup_configs(&mut cfg, api).await;
 
-        let _ = GLOBAL_SERVER_CONFIG.set(cfg);
+        set_global_server_config(cfg);
 
         Ok(())
     }
 }
 
 pub fn get_global_server_config() -> Option<Config> {
-    GLOBAL_SERVER_CONFIG.get().cloned()
+    GLOBAL_SERVER_CONFIG.read().ok().and_then(|guard| (*guard).clone())
+}
+
+pub fn set_global_server_config(cfg: Config) {
+    if let Ok(mut guard) = GLOBAL_SERVER_CONFIG.write() {
+        *guard = Some(cfg);
+    }
+}
+
+pub fn get_global_storage_class() -> Option<storageclass::Config> {
+    GLOBAL_STORAGE_CLASS.read().ok().map(|guard| (*guard).clone())
+}
+
+pub fn set_global_storage_class(cfg: storageclass::Config) {
+    if let Ok(mut guard) = GLOBAL_STORAGE_CLASS.write() {
+        *guard = cfg;
+    }
 }
 
 pub async fn init_global_config_sys(api: Arc<ECStore>) -> Result<()> {
@@ -262,3 +279,25 @@ pub fn init() {
     // Register all default configurations
     register_default_kvs(kvs)
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn global_server_config_set_and_get_roundtrip() {
+        init();
+        let mut cfg = Config::new();
+        let mut kvs = KVS::new();
+        kvs.insert("standard".to_string(), "EC:4".to_string());
+        cfg.0
+            .insert(STORAGE_CLASS_SUB_SYS.to_string(), HashMap::from([("_".to_string(), kvs)]));
+
+        set_global_server_config(cfg.clone());
+        let loaded = get_global_server_config().expect("global config should be set");
+        let sc_kvs = loaded
+            .get_value(STORAGE_CLASS_SUB_SYS, "_")
+            .expect("storage_class should exist");
+        assert_eq!(sc_kvs.get("standard"), "EC:4");
+    }
+}