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/set_disk.rs

@@ -41,7 +41,7 @@ use crate::{
         LifecycleOps, gen_transition_objname, get_transitioned_object_reader, put_restore_opts,
     },
     cache_value::metacache_set::{ListPathRawOptions, list_path_raw},
-    config::{GLOBAL_STORAGE_CLASS, storageclass},
+    config::{get_global_storage_class, storageclass},
     disk::{
         CheckPartsResp, DeleteOptions, DiskAPI, DiskInfo, DiskInfoOptions, DiskOption, DiskStore, FileInfoVersions,
         RUSTFS_META_BUCKET, RUSTFS_META_MULTIPART_BUCKET, RUSTFS_META_TMP_BUCKET, ReadMultipleReq, ReadMultipleResp, ReadOptions,
@@ -282,8 +282,7 @@ fn build_tiered_decommission_file_info(
     default_parity_count: usize,
     storage_class: Option<&str>,
 ) -> (FileInfo, usize) {
-    let parity_drives = GLOBAL_STORAGE_CLASS
-        .get()
+    let parity_drives = get_global_storage_class()
         .and_then(|sc| sc.get_parity_for_sc(storage_class.unwrap_or_default()))
         .unwrap_or(default_parity_count);
     let data_drives = disk_count - parity_drives;
@@ -783,7 +782,7 @@ impl ObjectIO for SetDisks {
             }
         }
         let sc_parity_drives = {
-            if let Some(sc) = GLOBAL_STORAGE_CLASS.get() {
+            if let Some(sc) = get_global_storage_class() {
                 sc.get_parity_for_sc(user_defined.get(AMZ_STORAGE_CLASS).cloned().unwrap_or_default().as_str())
             } else {
                 None
@@ -837,7 +836,7 @@ impl ObjectIO for SetDisks {
             let erasure = erasure_coding::Erasure::new(fi.erasure.data_blocks, fi.erasure.parity_blocks, fi.erasure.block_size);
 
             let is_inline_buffer = {
-                if let Some(sc) = GLOBAL_STORAGE_CLASS.get() {
+                if let Some(sc) = get_global_storage_class() {
                     sc.should_inline(erasure.shard_file_size(data.size()), opts.versioned)
                 } else {
                     false
@@ -3108,7 +3107,7 @@ impl MultipartOperations for SetDisks {
         }
 
         let sc_parity_drives = {
-            if let Some(sc) = GLOBAL_STORAGE_CLASS.get() {
+            if let Some(sc) = get_global_storage_class() {
                 sc.get_parity_for_sc(user_defined.get(AMZ_STORAGE_CLASS).cloned().unwrap_or_default().as_str())
             } else {
                 None