feat(scanner): emit excess alerts as S3 notification events

The excess-versions / excess-version-size / excess-folders alerts were
metrics-and-logs only; consoles and external auditors had no way to hear
them (rustfs/backlog#1868, HS-04). MinIO emits s3:ObjectManyVersions /
s3:ObjectLargeVersions / s3:PrefixManyFolders for the same conditions —
RustFS carries those as EventName::Scanner* with s3:Scanner:* wire names
that already existed unpublished.

The three alert sites now also dispatch through the standard event
pipeline (send_event via the storage_api owner facade), carrying the
actual values and thresholds in req_params and UserAgent "Scanner".
Without a cooldown a single over-threshold object would re-emit on every
~60s scan cycle, so emissions are edge-held per (kind, bucket, object)
for 24h (RUSTFS_SCANNER_ALERT_COOLDOWN_SECS, 0 = every cycle), backed by
a process-global map with a 4096-key hard cap that clears rather than
grows. Metrics and structured logs stay level-triggered every cycle;
only the notification events are held back. A restart resets the
cooldown deliberately: one re-emission per still-hot key buys back
visibility after the restarts that accompany incident response.

Tests pin the edge-hold semantics (first fires, immediate re-check held,
independent keys, cooldown expiry re-fires, zero cooldown always emits,
hard bound) in one sequential test for the process-global map, and pin
the emitted wire names against EventName's canonical string forms so a
subscribed bucket notification can never silently stop matching.
docs/operations/scanner-excess-alerts.md documents the three events,
the metric-vs-event cadence difference, and the HS-15 threshold deltas
(alert_excess_folders 65538 vs MinIO 50000 is deliberate: Proxmox
Backup Server chunk layout compatibility).

Closes rustfs/backlog#1868.

Co-Authored-By: heihutu <heihutu@gmail.com>

Cargo.lock

@@ -10251,6 +10251,7 @@ dependencies = [
  "rustfs-ecstore",
  "rustfs-filemeta",
  "rustfs-lock",
+ "rustfs-s3-types",
  "rustfs-storage-api",
  "rustfs-utils",
  "s3s",

crates/ecstore/src/api/mod.rs

@@ -380,7 +380,7 @@ pub mod erasure {
 
 pub mod event {
     pub use crate::event::name::EventName;
-    pub use crate::services::event_notification::{EventArgs, register_event_dispatch_hook};
+    pub use crate::services::event_notification::{EventArgs, register_event_dispatch_hook, send_event};
 }
 
 pub mod global {

crates/scanner/Cargo.toml

@@ -108,6 +108,9 @@ temp-env = { workspace = true }
 tempfile = { workspace = true }
 uuid = { workspace = true, features = ["v4", "serde", "fast-rng", "macro-diagnostics"] }
 tokio = { workspace = true, features = ["test-util", "fs", "rt-multi-thread"] }
+# Test-only: pins the emitted scanner alert wire names against the canonical
+# EventName string forms subscribers configure (rustfs/backlog#1868).
+rustfs-s3-types.workspace = true
 # Enables the shared MockWarmBackend / xl.meta assertion helpers exposed via
 # the ecstore `api::tier::test_util` facade module (rustfs/backlog#1148 ilm-6).
 rustfs-ecstore = { workspace = true, features = ["test-util"] }

crates/scanner/src/scanner_folder.rs

@@ -12,10 +12,10 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-use std::collections::HashSet;
+use std::collections::{HashMap, HashSet};
 use std::fs::FileType;
 use std::io::ErrorKind;
-use std::sync::{Arc, Once};
+use std::sync::{Arc, Mutex, Once};
 use std::time::{Duration, Instant, SystemTime};
 
 use crate::ReplTargetSizeSummary;
@@ -32,6 +32,7 @@ use crate::scanner_io::{
     SCANNER_SKIP_FILE_ERROR, ScannerIODisk as _, is_scanner_metadata_corrupt_error, is_scanner_metadata_transient_error,
 };
 use crate::sleeper::DynamicSleeper;
+use crate::storage_api::owner::{EcstoreEventArgs, ecstore_send_event};
 use metrics::{counter, describe_counter};
 use rustfs_common::heal_channel::{
     HEAL_DELETE_DANGLING, HealAdmissionDropReason, HealAdmissionResult, HealChannelPriority, HealChannelRequest,
@@ -97,6 +98,101 @@ const METRIC_SCANNER_EXCESS_FOLDERS_TOTAL: &str = "rustfs_scanner_excess_folders
 const METRIC_SCANNER_PENDING_HEAL_PRUNE_TOTAL: &str = "rustfs_scanner_pending_heal_prune_total";
 const METRIC_SCANNER_PENDING_HEAL_MALFORMED_TOTAL: &str = "rustfs_scanner_pending_heal_malformed_total";
 const MAX_PENDING_SCANNER_HEAL_RETRIES_PER_BUCKET: usize = 128;
+
+// --- scanner excess alerts as S3 notification events (rustfs/backlog#1868) --
+//
+// The excess-versions / excess-version-size / excess-folders alerts were
+// metrics-and-logs only; subscribers (consoles, external auditors) had no way
+// to hear them. MinIO emits s3:ObjectManyVersions / s3:ObjectLargeVersions /
+// s3:PrefixManyFolders for the same conditions — RustFS carries those as
+// EventName::Scanner* with the wire names below. Without a cooldown a single
+// over-threshold object would re-emit on every scan cycle (~a minute), so
+// emissions are edge-held per (kind, bucket, object) for 24h.
+
+/// `s3:Scanner:ManyVersions` (MinIO `s3:ObjectManyVersions`).
+pub const EVENT_SCANNER_MANY_VERSIONS: &str = "s3:Scanner:ManyVersions";
+/// `s3:Scanner:LargeVersions` (MinIO `s3:ObjectLargeVersions`).
+pub const EVENT_SCANNER_LARGE_VERSIONS: &str = "s3:Scanner:LargeVersions";
+/// `s3:Scanner:BigPrefix` (MinIO `s3:PrefixManyFolders`).
+pub const EVENT_SCANNER_BIG_PREFIX: &str = "s3:Scanner:BigPrefix";
+const ENV_SCANNER_ALERT_COOLDOWN_SECS: &str = "RUSTFS_SCANNER_ALERT_COOLDOWN_SECS";
+const DEFAULT_SCANNER_ALERT_COOLDOWN_SECS: u64 = 86_400;
+/// Hard cap on distinct cooldown keys; a pathological number of over-threshold
+/// objects clears the map wholesale instead of growing without bound (the
+/// worst case is one re-emission per still-hot key per scan cycle).
+const MAX_SCANNER_ALERT_COOLDOWN_KEYS: usize = 4096;
+
+/// Distinct alert kinds sharing one cooldown map.
+#[derive(Clone, Copy, Debug, PartialEq, Eq, Hash)]
+enum ScannerAlertKind {
+    ManyVersions,
+    LargeVersions,
+    BigPrefix,
+}
+
+type ScannerAlertCooldownKey = (ScannerAlertKind, String, String);
+type ScannerAlertCooldownMap = HashMap<ScannerAlertCooldownKey, Instant>;
+
+static SCANNER_ALERT_EMISSION_COOLDOWN: Mutex<Option<ScannerAlertCooldownMap>> = Mutex::new(None);
+
+fn scanner_alert_cooldown() -> Duration {
+    let raw = std::env::var(ENV_SCANNER_ALERT_COOLDOWN_SECS)
+        .ok()
+        .and_then(|v| v.parse::<u64>().ok());
+    Duration::from_secs(raw.unwrap_or(DEFAULT_SCANNER_ALERT_COOLDOWN_SECS))
+}
+
+/// Edge-held emission gate: returns `true` (and records the cooldown) only
+/// when this (kind, bucket, object) last fired longer than the cooldown ago —
+/// or never. Metrics and logs stay level-triggered every cycle; only the
+/// notification events are held back.
+fn scanner_alert_emission_allows(kind: ScannerAlertKind, bucket: &str, object: &str, cooldown: Duration) -> bool {
+    let key = (kind, bucket.to_string(), object.to_string());
+    let mut guard = SCANNER_ALERT_EMISSION_COOLDOWN
+        .lock()
+        .unwrap_or_else(|poison| poison.into_inner());
+    let guard = guard.get_or_insert_with(ScannerAlertCooldownMap::new);
+    let now = Instant::now();
+    // Expired entries leave first; the cap is still exceeded only when live
+    // keys alone overflow it, in which case a wholesale clear trades one
+    // extra emission per hot key for a hard memory bound.
+    if guard.len() >= MAX_SCANNER_ALERT_COOLDOWN_KEYS {
+        guard.retain(|_, fired_at| now.duration_since(*fired_at) < cooldown);
+        if guard.len() >= MAX_SCANNER_ALERT_COOLDOWN_KEYS {
+            guard.clear();
+        }
+    }
+    match guard.get(&key) {
+        Some(fired_at) if now.duration_since(*fired_at) < cooldown => false,
+        _ => {
+            guard.insert(key, now);
+            true
+        }
+    }
+}
+
+/// Emit a scanner alert as an S3 notification event through the standard
+/// dispatch pipeline. Fire-and-forget: the notify layer owns delivery,
+/// retry, and target filtering; the scanner never waits on it.
+fn emit_scanner_alert_event(event_name: &str, bucket: &str, object: &str, size: i64, details: &[(&str, String)]) {
+    let mut req_params = HashMap::with_capacity(details.len());
+    for (key, value) in details {
+        req_params.insert((*key).to_string(), value.clone());
+    }
+    ecstore_send_event(EcstoreEventArgs {
+        event_name: event_name.to_string(),
+        bucket_name: bucket.to_string(),
+        object: crate::ScannerObjectInfo {
+            bucket: bucket.to_string(),
+            name: object.to_string(),
+            size,
+            ..Default::default()
+        },
+        req_params,
+        user_agent: "Scanner".to_string(),
+        ..Default::default()
+    });
+}
 const MAX_PENDING_SCANNER_HEALS_PER_BUCKET: usize = 10_000;
 
 static SCANNER_INLINE_HEAL_WARN_ONCE: Once = Once::new();
@@ -1197,6 +1293,7 @@ impl ScannerItem {
     fn alert_excessive_versions(&self, remaining_versions: usize, cumulative_size: i64) {
         ensure_scanner_alert_metrics_registered();
         let (too_many_versions, too_large_versions) = should_alert_excessive_versions(remaining_versions, cumulative_size);
+        let object_path = self.object_path();
         if too_many_versions {
             global_metrics().record_scanner_source_executed(ScannerWorkSource::Alerts, 1);
             counter!(
@@ -1204,13 +1301,26 @@ impl ScannerItem {
                 "bucket" => self.bucket.clone()
             )
             .increment(1);
+            if scanner_alert_emission_allows(ScannerAlertKind::ManyVersions, &self.bucket, &object_path, scanner_alert_cooldown())
+            {
+                emit_scanner_alert_event(
+                    EVENT_SCANNER_MANY_VERSIONS,
+                    &self.bucket,
+                    &object_path,
+                    cumulative_size,
+                    &[
+                        ("versions", remaining_versions.to_string()),
+                        ("threshold", scanner_excess_versions_threshold().to_string()),
+                    ],
+                );
+            }
             warn!(
                 target: "rustfs::scanner::folder",
                 event = EVENT_SCANNER_ALERT_STATE,
                 component = LOG_COMPONENT_SCANNER,
                 subsystem = LOG_SUBSYSTEM_FOLDER,
                 bucket = %self.bucket,
-                object = %self.object_path(),
+                object = %object_path,
                 versions = remaining_versions,
                 threshold = scanner_excess_versions_threshold(),
                 state = "excess_versions",
@@ -1224,13 +1334,31 @@ impl ScannerItem {
                 "bucket" => self.bucket.clone()
             )
             .increment(1);
+            if scanner_alert_emission_allows(
+                ScannerAlertKind::LargeVersions,
+                &self.bucket,
+                &object_path,
+                scanner_alert_cooldown(),
+            ) {
+                emit_scanner_alert_event(
+                    EVENT_SCANNER_LARGE_VERSIONS,
+                    &self.bucket,
+                    &object_path,
+                    cumulative_size,
+                    &[
+                        ("versions", remaining_versions.to_string()),
+                        ("cumulativeSize", cumulative_size.to_string()),
+                        ("threshold", scanner_excess_version_size_threshold().to_string()),
+                    ],
+                );
+            }
             warn!(
                 target: "rustfs::scanner::folder",
                 event = EVENT_SCANNER_ALERT_STATE,
                 component = LOG_COMPONENT_SCANNER,
                 subsystem = LOG_SUBSYSTEM_FOLDER,
                 bucket = %self.bucket,
-                object = %self.object_path(),
+                object = %object_path,
                 versions = remaining_versions,
                 cumulative_size,
                 threshold = scanner_excess_version_size_threshold(),
@@ -1611,6 +1739,15 @@ impl FolderScanner {
             "root" => self.root.clone()
         )
         .increment(1);
+        if scanner_alert_emission_allows(ScannerAlertKind::BigPrefix, &self.root, folder, scanner_alert_cooldown()) {
+            emit_scanner_alert_event(
+                EVENT_SCANNER_BIG_PREFIX,
+                &self.root,
+                folder,
+                0,
+                &[("folders", total_folders.to_string()), ("threshold", threshold.to_string())],
+            );
+        }
         warn!(
             target: "rustfs::scanner::folder",
             event = EVENT_SCANNER_ALERT_STATE,
@@ -3076,6 +3213,90 @@ mod tests {
     #[cfg(unix)]
     use std::os::unix::fs::{PermissionsExt, symlink};
     use std::sync::Mutex;
+
+    /// Reset the process-global alert cooldown map; test-only.
+    fn reset_alert_cooldowns() {
+        *SCANNER_ALERT_EMISSION_COOLDOWN
+            .lock()
+            .unwrap_or_else(|poison| poison.into_inner()) = Some(ScannerAlertCooldownMap::new());
+    }
+
+    /// The emitted event-name strings must be exactly what `EventName`
+    /// serializes, or a bucket notification subscribed to the documented name
+    /// would silently never match (rustfs/backlog#1868).
+    #[test]
+    fn scanner_alert_wire_names_match_canonical_event_names() {
+        use rustfs_s3_types::EventName;
+        assert_eq!(EVENT_SCANNER_MANY_VERSIONS, EventName::ScannerManyVersions.to_string());
+        assert_eq!(EVENT_SCANNER_LARGE_VERSIONS, EventName::ScannerLargeVersions.to_string());
+        assert_eq!(EVENT_SCANNER_BIG_PREFIX, EventName::ScannerBigPrefix.to_string());
+    }
+
+    fn cooldown_map_len() -> usize {
+        SCANNER_ALERT_EMISSION_COOLDOWN
+            .lock()
+            .unwrap_or_else(|poison| poison.into_inner())
+            .as_ref()
+            .map(|map| map.len())
+            .unwrap_or(0)
+    }
+
+    /// Backdate every recorded cooldown so the next check fires again.
+    fn expire_all_alert_cooldowns(cooldown: Duration) {
+        let now = Instant::now();
+        let mut guard = SCANNER_ALERT_EMISSION_COOLDOWN
+            .lock()
+            .unwrap_or_else(|poison| poison.into_inner());
+        if let Some(map) = guard.as_mut() {
+            for fired_at in map.values_mut() {
+                if let Some(expired) = now.checked_sub(cooldown + Duration::from_secs(1)) {
+                    *fired_at = expired;
+                }
+            }
+        }
+    }
+
+    /// The emission gate is the only thing standing between an over-threshold
+    /// object and one S3 event per scan cycle, so its edge semantics get
+    /// pinned directly. All scenarios share one #[test] because the cooldown
+    /// map is process-global and parallel tests would read each other's
+    /// firings.
+    #[test]
+    fn scanner_alert_emission_is_edge_held_per_key_and_bounded() {
+        reset_alert_cooldowns();
+        let cooldown = Duration::from_secs(3600);
+
+        // First firing allows, an immediate re-check is held.
+        assert!(scanner_alert_emission_allows(ScannerAlertKind::ManyVersions, "bkt", "obj", cooldown));
+        assert!(!scanner_alert_emission_allows(ScannerAlertKind::ManyVersions, "bkt", "obj", cooldown));
+
+        // Different kind, object, and bucket are independent keys.
+        assert!(scanner_alert_emission_allows(ScannerAlertKind::LargeVersions, "bkt", "obj", cooldown));
+        assert!(scanner_alert_emission_allows(ScannerAlertKind::ManyVersions, "bkt", "other", cooldown));
+        assert!(scanner_alert_emission_allows(ScannerAlertKind::ManyVersions, "other", "obj", cooldown));
+        assert_eq!(cooldown_map_len(), 4);
+
+        // After the cooldown elapses the same key fires again.
+        expire_all_alert_cooldowns(cooldown);
+        assert!(scanner_alert_emission_allows(ScannerAlertKind::ManyVersions, "bkt", "obj", cooldown));
+
+        // A zero cooldown degenerates to always-emit (operators may want that).
+        assert!(scanner_alert_emission_allows(ScannerAlertKind::BigPrefix, "bkt", "dir", Duration::ZERO));
+        assert!(scanner_alert_emission_allows(ScannerAlertKind::BigPrefix, "bkt", "dir", Duration::ZERO));
+
+        // Hard bound: overflow the cap with zero-cooldown keys and confirm the
+        // map clears rather than growing past it.
+        reset_alert_cooldowns();
+        for index in 0..=(MAX_SCANNER_ALERT_COOLDOWN_KEYS + 8) {
+            let _ = scanner_alert_emission_allows(ScannerAlertKind::BigPrefix, "bkt", &format!("dir-{index}"), Duration::ZERO);
+        }
+        assert!(
+            cooldown_map_len() <= MAX_SCANNER_ALERT_COOLDOWN_KEYS,
+            "cooldown map must stay bounded, got {}",
+            cooldown_map_len()
+        );
+    }
+
     use std::sync::atomic::{AtomicBool, AtomicUsize, Ordering};
     use temp_env::{with_var, with_var_unset};
     use tracing_subscriber::fmt::MakeWriter;

crates/scanner/src/storage_api.rs

@@ -78,6 +78,7 @@ pub(crate) use rustfs_ecstore::api::disk::{
 pub(crate) use rustfs_ecstore::api::error::{
     Error as EcstoreErrorType, Result as EcstoreResultType, StorageError as EcstoreStorageError,
 };
+pub(crate) use rustfs_ecstore::api::event::{EventArgs as EcstoreEventArgs, send_event as ecstore_send_event};
 #[cfg(test)]
 pub(crate) use rustfs_ecstore::api::layout::{
     EndpointServerPools as EcstoreEndpointServerPools, Endpoints as EcstoreEndpoints, PoolEndpoints as EcstorePoolEndpoints,
@@ -110,8 +111,8 @@ pub(crate) mod owner {
         ECSTORE_BUCKET_META_PREFIX, ECSTORE_RUSTFS_META_BUCKET, ECSTORE_STORAGE_FORMAT_FILE, ECSTORE_STORAGECLASS_RRS,
         ECSTORE_STORAGECLASS_STANDARD, ECSTORE_TRANSITION_COMPLETE, EcstoreBucketTargetSys, EcstoreBucketVersioningSys,
         EcstoreDisk, EcstoreDiskAPI, EcstoreDiskBytes, EcstoreDiskError, EcstoreDiskInfo, EcstoreDiskInfoOptions,
-        EcstoreDiskLocation, EcstoreDiskResult, EcstoreErrorType, EcstoreEvaluator, EcstoreEvent, EcstoreLcEventSrc,
+        EcstoreDiskLocation, EcstoreDiskResult, EcstoreErrorType, EcstoreEvaluator, EcstoreEvent, EcstoreEventArgs,
-        EcstoreLifecycle, EcstoreListPathRawOptions, EcstoreNsScannerOpenRequest, EcstoreObjectOpts,
+        EcstoreLcEventSrc, EcstoreLifecycle, EcstoreListPathRawOptions, EcstoreNsScannerOpenRequest, EcstoreObjectOpts,
         EcstoreReplicationConfigurationExt, EcstoreReplicationScannerBridge, EcstoreResultType, EcstoreScanGuard,
         EcstoreSetDisks, EcstoreStorageError, EcstoreStore, EcstoreTierConfig, EcstoreVersioningApi,
         ScannerReplicationHealObject, ScannerReplicationHealResult, ScannerReplicationQueueAdmission, ecstore_apply_expiry_rule,
@@ -121,7 +122,7 @@ pub(crate) mod owner {
         ecstore_is_erasure_sd, ecstore_is_reserved_or_invalid_bucket, ecstore_list_path_raw,
         ecstore_object_opts_from_object_info, ecstore_path2_bucket_object, ecstore_path2_bucket_object_with_base_path,
         ecstore_read_config, ecstore_replace_bucket_usage_memory_from_info, ecstore_resolve_object_store_handle,
-        ecstore_save_config, scanner_replication_config_for_lifecycle_eval,
+        ecstore_save_config, ecstore_send_event, scanner_replication_config_for_lifecycle_eval,
     };
 
     #[cfg(test)]

docs/operations/scanner-excess-alerts.md

@@ -0,0 +1,35 @@
+# Scanner 超限告警：指标、S3 事件与阈值
+
+日期：2026-08-18（rustfs/backlog#1868 / HS-04，含 HS-15 阈值差异说明）
+
+后台 scanner 在扫描过程中检测三类"超限"状态并对外告警。本文说明每类告警的触发条件、可订阅的 S3 事件、冷却语义，以及与 MinIO 的阈值差异，供运维排障与事件消费方对接。
+
+## 三类告警
+
+| 告警 | 触发条件（任一扫描周期） | 指标 | S3 事件（RustFS wire 名） | MinIO 对应事件名 |
+|---|---|---|---|---|
+| 版本数超限 | 单对象保留版本数 ≥ `scanner:alert_excess_versions` | `rustfs_scanner_excess_object_versions_total{bucket}` | `s3:Scanner:ManyVersions` | `s3:ObjectManyVersions` |
+| 版本总大小超限 | 单对象全部版本累计字节 ≥ `scanner:alert_excess_version_size` | `rustfs_scanner_excess_object_version_size_total{bucket}` | `s3:Scanner:LargeVersions` | `s3:ObjectLargeVersions` |
+| 子目录数超限 | 单目录直接子目录数 > `scanner:alert_excess_folders` | `rustfs_scanner_excess_folders_total{root}` | `s3:Scanner:BigPrefix` | `s3:PrefixManyFolders` |
+
+订阅方式与普通桶通知一致：对目标桶配置 notification，事件名填上表 RustFS wire 名（或通配 `s3:Scanner:*`）。事件以 `UserAgent: Scanner` 标记来源，`req_params` 携带实际值与阈值（`versions` / `cumulativeSize` / `folders` / `threshold`），便于消费方直接判断严重程度。
+
+## 指标与事件的触发节奏不同
+
+- **指标与结构化日志是电平触发**：只要对象仍在阈值之上，每个扫描周期都会计数/打日志（默认周期约 60s，见 `scanner:speed`）。
+- **S3 事件是边沿触发 + 冷却**：同一 (告警类型， 桶, 对象) 在冷却窗口内只发一次，默认 24 小时（`RUSTFS_SCANNER_ALERT_COOLDOWN_SECS`，设 0 表示每周期都发）。窗口过后对象仍超限会再次发出。冷却表在进程内有 4096 条硬顶，超限清空重建（最坏情况是每个仍超限的 key 多发一次）。
+- 进程重启会重置冷却（重启后每个仍超限的对象会再发一次）——这是有意为之：重启常伴随排障，重发提供可见性。
+
+## 阈值默认值与 MinIO 差异（HS-15）
+
+| 配置键 | ENV | RustFS 默认 | MinIO 默认 | 差异说明 |
+|---|---|---|---|---|
+| `scanner:alert_excess_versions` | `RUSTFS_SCANNER_ALERT_EXCESS_VERSIONS` | 100 | 100 | 一致 |
+| `scanner:alert_excess_version_size` | `RUSTFS_SCANNER_ALERT_EXCESS_VERSION_SIZE` | 1 TiB | 1 TB | 语义同量级，单位口径不同（TiB vs TB） |
+| `scanner:alert_excess_folders` | `RUSTFS_SCANNER_ALERT_EXCESS_FOLDERS` | 65538 | 50000 | **有意差异**：65538 兼容 Proxmox Backup Server 的 chunk 布局（每目录 65536 个 chunk + 目录自身条目），按 MinIO 的 50000 会对 PBS 用户持续误报。如需与 MinIO 行为一致可显式配置为 50000 |
+
+三个键均支持 env 与 admin config（`PUT /rustfs/admin/v3/config` 的 `scanner` 子系统）双通道，热更新即时生效。
+
+## 事件名映射的由来
+
+RustFS 的事件枚举（`rustfs_s3_types::EventName::ScannerManyVersions/LargeVersions/BigPrefix`）沿用仓库既有 wire 名 `s3:Scanner:*`（与 MinIO 的 `s3:ObjectManyVersions` 字面不同，枚举注释中保留了映射关系）。订阅方应以本文的 RustFS wire 名为准；如需 MinIO 字面兼容，请在 console/消费侧做名称映射，不要修改已发布的 wire 名。