fix: Fix republishing volumes after a Node restart

CHANGELOG.md

@@ -17,12 +17,15 @@ All notable changes to this project will be documented in this file.
 ### Fixed
 
 - Give RBAC permission to `delete` Services, which is needed to set an ownerRef on already existing Services ([#283]).
+- Fix the error "failed to write content: File exists (os error 17)" after a
+  Node restart ([#284]).
 
 [#267]: https://github.com/stackabletech/listener-operator/pull/267
 [#268]: https://github.com/stackabletech/listener-operator/pull/268
 [#279]: https://github.com/stackabletech/listener-operator/pull/279
 [#282]: https://github.com/stackabletech/listener-operator/pull/282
 [#283]: https://github.com/stackabletech/listener-operator/pull/283
+[#284]: https://github.com/stackabletech/listener-operator/pull/284
 
 ## [24.11.1] - 2025-01-10
 

rust/operator-binary/src/csi_server/node.rs

@@ -591,14 +591,26 @@ mod pod_dir {
             }
             default_addr_dir.get_or_insert(addr_dir);
         }
-        tokio::fs::symlink(
-            default_addr_dir
-                .context(NoDefaultAddressSnafu)?
-                .strip_prefix(target_path)
-                .context(DefaultAddrIsOutsideRootSnafu)?,
-            target_path.join("default-address"),
-        )
-        .await?;
+
+        let relative_default_addr_dir = default_addr_dir
+            .context(NoDefaultAddressSnafu)?
+            .strip_prefix(target_path)
+            .context(DefaultAddrIsOutsideRootSnafu)?
+            .to_owned();
+        let default_addr_dir_link = target_path.join("default-address");
+        // Check if the symlink needs to be updated
+        if tokio::fs::read_link(&default_addr_dir_link)
+            .await
+            .ok()
+            .as_ref()
+            != Some(&relative_default_addr_dir)
+        {
+            // Remove any existing symlink because `tokio::fs::symlink` fails if it already exists.
+            // This happens if the node was restarted. The pod then restarts with the same UID and
+            // the pre-populated volume.
+            let _ = tokio::fs::remove_file(&default_addr_dir_link).await;
+            tokio::fs::symlink(relative_default_addr_dir, &default_addr_dir_link).await?;
+        }
         Ok(())
     }
 }

rust/operator-binary/src/main.rs

@@ -97,7 +97,7 @@ async fn main() -> anyhow::Result<()> {
             .await?;
             if csi_endpoint
                 .symlink_metadata()
-                .map_or(false, |meta| meta.file_type().is_socket())
+                .is_ok_and(|meta| meta.file_type().is_socket())
             {
                 let _ = std::fs::remove_file(&csi_endpoint);
             }