Add try/except around unpackSpecialData (#809)

compareDatabases should be able to continue to run even if unpackSpecialData fails.

Some parameters are not able to be compared, which in a recent scenario led to a failure inside unpackSpecialData. This PR adds the try/except so that there is just an error and not a failure, and it also adds a the traceback to the log printout so parameters that cause this step to fail can be more easily addressed / manually compared.

armi/bookkeeping/db/compareDB3.py

@@ -47,6 +47,7 @@
 import collections
 import os
 import re
+import traceback
 
 from tabulate import tabulate
 import h5py
@@ -360,8 +361,15 @@ def _diffSpecialData(
     if not attrsMatch:
         return
 
-    src = database3.unpackSpecialData(srcData[()], srcData.attrs, paramName)
-    ref = database3.unpackSpecialData(refData[()], refData.attrs, paramName)
+    try:
+        src = database3.unpackSpecialData(srcData[()], srcData.attrs, paramName)
+        ref = database3.unpackSpecialData(refData[()], refData.attrs, paramName)
+    except Exception:
+        runLog.error(
+            f"Unable to unpack special data for paramName {paramName}. "
+            f"{traceback.format_exc()}",
+        )
+        return
 
     diff = []
     for dSrc, dRef in zip(src.tolist(), ref.tolist()):

armi/bookkeeping/db/tests/test_comparedb3.py

@@ -204,6 +204,21 @@ def test_diffSpecialData(self):
                 self.assertEqual(dr.nDiffs(), 0)
                 self.assertIn("Special formatting parameters for", mock._outputStream)
 
+            # make an H5 datasets that will cause unpackSpecialData to fail
+            f4 = h5py.File("test_diffSpecialData4.hdf5", "w")
+            refData4 = f4.create_dataset("numberDensities", data=a2)
+            refData4.attrs["shapes"] = "2"
+            refData4.attrs["numDens"] = a2
+            f5 = h5py.File("test_diffSpecialData5.hdf5", "w")
+            srcData5 = f5.create_dataset("numberDensities", data=a2)
+            srcData5.attrs["shapes"] = "2"
+            srcData5.attrs["numDens"] = a2
+
+            # there should an exception
+            with self.assertRaises(Exception) as e:
+                _diffSpecialData(refData4, srcData5, out, dr)
+                self.assertIn("Unable to unpack special data for paramName", e)
+
     def test_diffSimpleData(self):
         dr = DiffResults(0.01)
 

doc/release/0.2.rst

@@ -22,6 +22,7 @@ What's new in ARMI
 #. Introduction of axial expansion changer to enable component-level axial expansion of assemblies.
 #. Add setting ``inputHeightsConsideredHot`` to enable thermal expansion of assemblies at BOL.
 #. Add blueprints setting, ``axial expansion target component``, to enable users to manually set a "target component" for axial expansion.
+#. Allow database comparison to continue even if ``unpackSpecialData`` fails. 
 #. TBD
 
 Bug fixes