하드링크 실패 시 심볼릭 링크로 만들어보기

src/main/java/com/kamco/cd/training/train/service/TmpDatasetService.java

@@ -74,7 +74,6 @@ public class TmpDatasetService {
   }
 
   private long link(Path tmp, String type, String part, String fullPath) throws IOException {
-
     if (fullPath == null || fullPath.isBlank()) return 0;
 
     Path src = Path.of(fullPath);
@@ -87,12 +86,26 @@ public class TmpDatasetService {
     String fileName = src.getFileName().toString();
     Path dst = tmp.resolve(type).resolve(part).resolve(fileName);
 
-    // 충돌 시 덮어쓰기
+    Files.createDirectories(dst.getParent());
+
     if (Files.exists(dst)) {
       Files.delete(dst);
     }
 
+    try {
       Files.createLink(dst, src);
+      log.info("hardlink created: {} -> {}", dst, src);
+    } catch (FileSystemException e) {
+      if (e.getMessage() != null && e.getMessage().contains("Invalid cross-device link")) {
+        log.warn(
+            "Hardlink failed due to cross-device link. Fallback to symlink. src={}, dst={}",
+            src,
+            dst);
+        Files.createSymbolicLink(dst, src);
+      } else {
+        throw e;
+      }
+    }
 
     return 1;
   }