From be3e74c9d6ec26b5b945c31cd070a402c6a80e1e Mon Sep 17 00:00:00 2001
From: igalshilman <igal@restate.dev>
Date: Tue, 19 Nov 2024 16:30:01 +0100
Subject: [PATCH] Add logging

---
 .../metadata_store/providers/objstore/glue.rs |  4 ++--
 .../providers/objstore/metadata_impl.rs       | 19 +++++++++++++++++--
 2 files changed, 19 insertions(+), 4 deletions(-)

diff --git a/crates/core/src/metadata_store/providers/objstore/glue.rs b/crates/core/src/metadata_store/providers/objstore/glue.rs
index 070e179ae..9803613a6 100644
--- a/crates/core/src/metadata_store/providers/objstore/glue.rs
+++ b/crates/core/src/metadata_store/providers/objstore/glue.rs
@@ -68,7 +68,7 @@ impl Server {
         // pre-fetch the latest version
         // TODO: should there be a limit before we give up? figure out how to exit gracefully?
         loop {
-            match delegate.load_last_version().await {
+            match delegate.load_latest_version().await {
                 Ok(_) => {
                     break;
                 }
@@ -85,7 +85,7 @@ impl Server {
             select! {
                 _ = refresh.tick() => {
                     // periodically check for a newer version
-                    if let Err(e) = delegate.load_last_version().await {
+                    if let Err(e) = delegate.load_latest_version().await {
                         tracing::warn!(error = ?e, "error while loading latest metastore version, will retry in the next interval.");
                     }
                 }
diff --git a/crates/core/src/metadata_store/providers/objstore/metadata_impl.rs b/crates/core/src/metadata_store/providers/objstore/metadata_impl.rs
index 0a7a6c877..082c95f09 100644
--- a/crates/core/src/metadata_store/providers/objstore/metadata_impl.rs
+++ b/crates/core/src/metadata_store/providers/objstore/metadata_impl.rs
@@ -24,7 +24,7 @@ impl ObjectStoreMetastoreImpl {
         }
     }
 
-    pub(crate) async fn load_last_version(&self) -> Result<(), GenericError> {
+    pub(crate) async fn load_latest_version(&self) -> Result<(), GenericError> {
         let latest_version = self.version_repository.get_latest_version().await?;
 
         let Some(latest) = latest_version else {
@@ -37,10 +37,19 @@ impl ObjectStoreMetastoreImpl {
         match cached_version.cmp(&latest) {
             Ordering::Equal => {
                 // cache hit
+                tracing::trace!(
+                    "No new version detected (current version: {})",
+                    cached_version
+                );
                 Ok(())
             }
             Ordering::Less => {
                 // cache miss
+                tracing::info!(
+                    "New metadata version discovered {} (previously known was {})",
+                    latest,
+                    cached_version
+                );
                 let latest_store_buf = self.version_repository.get_version(latest).await?;
                 let last_store = ImmutableStore::deserialize(latest_store_buf)?;
                 self.latest_store_cache.store(Arc::new(last_store));
@@ -80,6 +89,10 @@ impl ObjectStoreMetastoreImpl {
             {
                 Ok(_) => {
                     // All good!
+                    tracing::info!(
+                        "successfully published a new metadata store version {}",
+                        new_store.current_version()
+                    );
                     self.latest_store_cache.store(Arc::new(new_store));
                     return Ok(());
                 }
@@ -91,7 +104,9 @@ impl ObjectStoreMetastoreImpl {
                     };
                     tokio::time::sleep(tokio::time::Duration::from_millis(delay)).await;
                     // refresh and try again
-                    self.load_last_version().await.map_err(WriteError::Store)?;
+                    self.load_latest_version()
+                        .await
+                        .map_err(WriteError::Store)?;
                 }
                 Err(e) => {
                     return Err(WriteError::Store(e.into()));