handle ENOENT in _finalize_restore

Signed-off-by: Utkarsh Srivastava <srivastavautkarsh8097@gmail.com>

handle ENOENT in open

Signed-off-by: Utkarsh Srivastava <srivastavautkarsh8097@gmail.com>
(cherry picked from commit ed61d22)
(cherry picked from commit 0562584)

src/sdk/nsfs_glacier_backend/tapecloud.js

@@ -359,7 +359,17 @@ class TapeCloudGlacierBackend extends GlacierBackend {
         const entry = new NewlineReaderEntry(fs_context, entry_path);
         let fh = null;
         try {
-            fh = await entry.open("r");
+            try {
+                fh = await entry.open("r");
+            } catch (error) {
+                // restore does check if a file exist or not before triggering eeadm call but the file could get deleted
+                // after `restore` performs that check so check it here once again
+                if (error.code === 'ENOENT') {
+                    dbg.warn(`TapeCloudGlacierBackend._finalize_restore: log entry unexpectedly not found: ${entry.path}`);
+                    return;
+                }
+                throw error;
+            }
 
             const stat = await fh.stat(fs_context, {
                 xattr_get_keys: [

src/test/unit_tests/test_nsfs_glacier_backend.js

@@ -278,6 +278,11 @@ mocha.describe('nsfs_glacier', async () => {
             assert(failure_stats.xattr[GlacierBackend.XATTR_RESTORE_REQUEST]);
         });
 
+		mocha.it('_finalize_restore should tolerate deleted objects', async () => {
+            // should not throw error if the path does not exist
+            await backend._finalize_restore(glacier_ns.prepare_fs_context(dummy_object_sdk), '/path/does/not/exist');
+		});
+
         mocha.it('generate_expiry should round up the expiry', () => {
             const now = new Date();
             const pivot_time = new Date(now);