refactor(app): add AppContext skeleton wiring (#1909)

rustfs/src/app/context.rs

@@ -0,0 +1,113 @@
+// Copyright 2024 RustFS Team
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+//! Application-layer dependency context.
+//! This module introduces explicit dependency injection entry points
+//! for storage, IAM, and KMS handles.
+#![allow(dead_code)]
+
+use rustfs_ecstore::store::ECStore;
+use rustfs_iam::{store::object::ObjectStore, sys::IamSys};
+use rustfs_kms::KmsServiceManager;
+use std::sync::{Arc, OnceLock};
+
+/// IAM interface for application-layer use-cases.
+pub trait IamInterface: Send + Sync {
+    fn handle(&self) -> Arc<IamSys<ObjectStore>>;
+}
+
+/// KMS interface for application-layer use-cases.
+pub trait KmsInterface: Send + Sync {
+    fn handle(&self) -> Arc<KmsServiceManager>;
+}
+
+/// Default IAM interface adapter.
+pub struct IamHandle {
+    iam: Arc<IamSys<ObjectStore>>,
+}
+
+impl IamHandle {
+    pub fn new(iam: Arc<IamSys<ObjectStore>>) -> Self {
+        Self { iam }
+    }
+}
+
+impl IamInterface for IamHandle {
+    fn handle(&self) -> Arc<IamSys<ObjectStore>> {
+        self.iam.clone()
+    }
+}
+
+/// Default KMS interface adapter.
+pub struct KmsHandle {
+    kms: Arc<KmsServiceManager>,
+}
+
+impl KmsHandle {
+    pub fn new(kms: Arc<KmsServiceManager>) -> Self {
+        Self { kms }
+    }
+}
+
+impl KmsInterface for KmsHandle {
+    fn handle(&self) -> Arc<KmsServiceManager> {
+        self.kms.clone()
+    }
+}
+
+/// Application-layer context with explicit dependencies.
+#[derive(Clone)]
+pub struct AppContext {
+    object_store: Arc<ECStore>,
+    iam: Arc<dyn IamInterface>,
+    kms: Arc<dyn KmsInterface>,
+}
+
+impl AppContext {
+    pub fn new(object_store: Arc<ECStore>, iam: Arc<dyn IamInterface>, kms: Arc<dyn KmsInterface>) -> Self {
+        Self { object_store, iam, kms }
+    }
+
+    pub fn with_default_interfaces(
+        object_store: Arc<ECStore>,
+        iam: Arc<IamSys<ObjectStore>>,
+        kms: Arc<KmsServiceManager>,
+    ) -> Self {
+        Self::new(object_store, Arc::new(IamHandle::new(iam)), Arc::new(KmsHandle::new(kms)))
+    }
+
+    pub fn object_store(&self) -> Arc<ECStore> {
+        self.object_store.clone()
+    }
+
+    pub fn iam(&self) -> Arc<dyn IamInterface> {
+        self.iam.clone()
+    }
+
+    pub fn kms(&self) -> Arc<dyn KmsInterface> {
+        self.kms.clone()
+    }
+}
+
+static GLOBAL_APP_CONTEXT: OnceLock<Arc<AppContext>> = OnceLock::new();
+
+/// Initialize global application context once and return the canonical instance.
+pub fn init_global_app_context(context: AppContext) -> Arc<AppContext> {
+    GLOBAL_APP_CONTEXT.get_or_init(|| Arc::new(context)).clone()
+}
+
+/// Get global application context if it has been initialized.
+pub fn get_global_app_context() -> Option<Arc<AppContext>> {
+    GLOBAL_APP_CONTEXT.get().cloned()
+}

rustfs/src/app/mod.rs

@@ -14,3 +14,5 @@
 
 //! Application layer module entry.
 //! Concrete use-case modules will be introduced incrementally in Phase 3.
+
+pub mod context;

rustfs/src/main.rs

@@ -28,6 +28,7 @@ mod update;
 mod version;
 
 // Ensure the correct path for parse_license is imported
+use crate::app::context::{AppContext, init_global_app_context};
 use crate::init::{
     add_bucket_notification_configuration, init_buffer_profile_system, init_kms_system, init_update_check, print_server_info,
 };
@@ -365,6 +366,11 @@ async fn run(config: config::Config) -> Result<()> {
     init_iam_sys(store.clone()).await.map_err(Error::other)?;
     readiness.mark_stage(SystemStage::IamReady);
 
+    let iam_interface =
+        rustfs_iam::get().map_err(|e| Error::other(format!("initialize app context IAM dependency failed: {e}")))?;
+    let kms_interface = rustfs_kms::get_global_kms_service_manager().unwrap_or_else(rustfs_kms::init_global_kms_service_manager);
+    let _app_context = init_global_app_context(AppContext::with_default_interfaces(store.clone(), iam_interface, kms_interface));
+
     add_bucket_notification_configuration(buckets.clone()).await;
 
     // Initialize the global notification system