Inject GlobalReadiness into HTTP server pipeline and gate traffic until FullReady (#1255)

crates/common/src/lib.rs

@@ -19,6 +19,10 @@ pub mod globals;
 pub mod heal_channel;
 pub mod last_minute;
 pub mod metrics;
+mod readiness;
+
+pub use globals::*;
+pub use readiness::{GlobalReadiness, SystemStage};
 
 // is ','
 pub static DEFAULT_DELIMITER: u8 = 44;

crates/common/src/readiness.rs

@@ -0,0 +1,136 @@
+// 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.
+
+use std::sync::atomic::{AtomicU8, Ordering};
+
+/// Represents the various stages of system startup
+#[repr(u8)]
+pub enum SystemStage {
+    Booting = 0,
+    StorageReady = 1, // Disks online, Quorum met
+    IamReady = 2,     // Users and Policies loaded into cache
+    FullReady = 3,    // System ready to serve all traffic
+}
+
+/// Global readiness tracker for the service
+/// This struct uses atomic operations to track the readiness status of various components
+/// of the service in a thread-safe manner.
+pub struct GlobalReadiness {
+    status: AtomicU8,
+}
+
+impl Default for GlobalReadiness {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
+impl GlobalReadiness {
+    /// Create a new GlobalReadiness instance with initial status as Starting
+    /// # Returns
+    /// A new instance of GlobalReadiness
+    pub fn new() -> Self {
+        Self {
+            status: AtomicU8::new(SystemStage::Booting as u8),
+        }
+    }
+
+    /// Update the system to a new stage
+    ///
+    /// # Arguments
+    /// * `step` - The SystemStage step to mark as ready
+    pub fn mark_stage(&self, step: SystemStage) {
+        self.status.fetch_max(step as u8, Ordering::SeqCst);
+    }
+
+    /// Check if the service is fully ready
+    /// # Returns
+    /// `true` if the service is fully ready, `false` otherwise
+    pub fn is_ready(&self) -> bool {
+        self.status.load(Ordering::SeqCst) == SystemStage::FullReady as u8
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use std::sync::Arc;
+    use std::thread;
+
+    #[test]
+    fn test_initial_state() {
+        let readiness = GlobalReadiness::new();
+        assert!(!readiness.is_ready());
+        assert_eq!(readiness.status.load(Ordering::SeqCst), SystemStage::Booting as u8);
+    }
+
+    #[test]
+    fn test_mark_stage_progression() {
+        let readiness = GlobalReadiness::new();
+        readiness.mark_stage(SystemStage::StorageReady);
+        assert!(!readiness.is_ready());
+        assert_eq!(readiness.status.load(Ordering::SeqCst), SystemStage::StorageReady as u8);
+
+        readiness.mark_stage(SystemStage::IamReady);
+        assert!(!readiness.is_ready());
+        assert_eq!(readiness.status.load(Ordering::SeqCst), SystemStage::IamReady as u8);
+
+        readiness.mark_stage(SystemStage::FullReady);
+        assert!(readiness.is_ready());
+    }
+
+    #[test]
+    fn test_no_regression() {
+        let readiness = GlobalReadiness::new();
+        readiness.mark_stage(SystemStage::FullReady);
+        readiness.mark_stage(SystemStage::IamReady); // Should not regress
+        assert!(readiness.is_ready());
+    }
+
+    #[test]
+    fn test_concurrent_marking() {
+        let readiness = Arc::new(GlobalReadiness::new());
+        let mut handles = vec![];
+
+        for _ in 0..10 {
+            let r = Arc::clone(&readiness);
+            handles.push(thread::spawn(move || {
+                r.mark_stage(SystemStage::StorageReady);
+                r.mark_stage(SystemStage::IamReady);
+                r.mark_stage(SystemStage::FullReady);
+            }));
+        }
+
+        for h in handles {
+            h.join().unwrap();
+        }
+
+        assert!(readiness.is_ready());
+    }
+
+    #[test]
+    fn test_is_ready_only_at_full_ready() {
+        let readiness = GlobalReadiness::new();
+        assert!(!readiness.is_ready());
+
+        readiness.mark_stage(SystemStage::StorageReady);
+        assert!(!readiness.is_ready());
+
+        readiness.mark_stage(SystemStage::IamReady);
+        assert!(!readiness.is_ready());
+
+        readiness.mark_stage(SystemStage::FullReady);
+        assert!(readiness.is_ready());
+    }
+}