use local reference files as fallback

csst_common/data_manager.py

@@ -529,27 +529,30 @@ class CsstMsDataManager:
              'shutter': '/crdsroot/references/msc/csst_msc_ms_shutter_11_000001.fits'}
         """
         if self.crds.is_available:
-            print("CRDS available, use refs from CRDS ...")
-            return self.crds.retry(
-                self.crds.get_refs, 3,
-                file_path=self.l0_detector(detector)
-            )
-        else:
-            print("CRDS unavailable, use refs from local files ...")
-            refs = dict()
-            if self.datatype == "mbi":
-                ref_types = ["bias", "dark", "ledflat", "shutter"]
-            else:
-                ref_types = ["bias", "dark", "ledflat"]
-            for ref_type in ref_types:
-                fp = os.path.join(
-                    self.path_aux,
-                    "C6.2_ref_crds",
-                    "csst_msc_ms_{}_{:02d}_{:06d}.fits".format(ref_type, detector, 1)
+            try:
+                print("CRDS available, use refs from CRDS ...")
+                return self.crds.retry(
+                    self.crds.get_refs, 3,
+                    file_path=self.l0_detector(detector)
                 )
-                assert os.path.exists(fp), f"File not found: [{fp}]"
-                refs[ref_type] = fp
-            return refs
+            except BaseException as e:
+                print("CRDS reference access failed! ", e)
+
+        print("Use refs from local files ...")
+        refs = dict()
+        if self.datatype == "mbi":
+            ref_types = ["bias", "dark", "ledflat", "shutter"]
+        else:
+            ref_types = ["bias", "dark", "ledflat"]
+        for ref_type in ref_types:
+            fp = os.path.join(
+                self.path_aux,
+                "C6.2_ref_crds",
+                "csst_msc_ms_{}_{:02d}_{:06d}.fits".format(ref_type, detector, 1)
+            )
+            assert os.path.exists(fp), f"File not found: [{fp}]"
+            refs[ref_type] = fp
+        return refs
 
     def get_bias(self, detector=6):
         """ get bias data """