Allow for loading from databases with extra parameters (#372)

This allows loading from old databases when parameters have since been removed from the application. In such cases, a warning will be issued.

armi/bookkeeping/db/database3.py

@@ -358,6 +358,7 @@ def loadState(
                         statePointName=timeStepName,
                         cs=self.cs,
                         bp=self.r.blueprints,
+                        allowMissing=True,
                     )
                     break
         else:
@@ -989,7 +990,9 @@ def syncToSharedFolder(self):
         self.h5db.flush()
         shutil.copy(self._fullPath, self._fileName)
 
-    def load(self, cycle, node, cs=None, bp=None, statePointName=None):
+    def load(
+        self, cycle, node, cs=None, bp=None, statePointName=None, allowMissing=False
+    ):
         """Load a new reactor from (cycle, node).
 
         Case settings, blueprints, and geom can be provided by the client, or read from
@@ -1008,6 +1011,11 @@ def load(self, cycle, node, cs=None, bp=None, statePointName=None):
             if not provided one is read from the database
         bp : armi.reactor.Blueprints (Optional)
             if not provided one is read from the database
+        statePointName : str
+            Optional arbitrary statepoint name (e.g., "special" for "c00n00-special/")
+        allowMissing : bool
+            Whether to emit a warning, rather than crash if reading a database
+            with undefined parameters. Default False.
 
         Returns
         -------
@@ -1028,7 +1036,7 @@ def load(self, cycle, node, cs=None, bp=None, statePointName=None):
 
         # populate data onto initialized components
         for compType, compTypeList in groupedComps.items():
-            self._readParams(h5group, compType, compTypeList)
+            self._readParams(h5group, compType, compTypeList, allowMissing=allowMissing)
 
         # assign params from blueprints
         if bp is not None:
@@ -1246,7 +1254,7 @@ def _addHomogenizedNumberDensityParams(blocks, h5group):
             h5group.create_dataset(nucName, data=numDens, compression="gzip")
 
     @staticmethod
-    def _readParams(h5group, compTypeName, comps):
+    def _readParams(h5group, compTypeName, comps, allowMissing=False):
         g = h5group[compTypeName]
 
         renames = armi.getApp().getParamRenames()
@@ -1264,11 +1272,21 @@ def _readParams(h5group, compTypeName, comps):
                 pDef = pDefs[paramName]
             except KeyError:
                 if re.match(r"^n[A-Z][a-z]?\d*", paramName):
-                    # This is a temporary viz param made by _addHomogenizedNumberDensities
-                    # ignore it safely
+                    # This is a temporary viz param (number density) made by
+                    # _addHomogenizedNumberDensityParams ignore it safely
                     continue
                 else:
-                    raise
+                    # If a parameter exists in the database but not in the application
+                    # reading it, we can technically keep going. Since this may lead to
+                    # potential correctness issues, raise a warning
+                    if allowMissing:
+                        runLog.warning(
+                            "Found `{}` parameter `{}` in the database, which is not defined. "
+                            "Ignoring it.".format(compTypeName, paramName)
+                        )
+                        continue
+                    else:
+                        raise
 
             data = dataSet[:]
             attrs = _resolveAttrs(dataSet.attrs, h5group)

armi/bookkeeping/db/tests/test_database3.py

@@ -101,6 +101,9 @@ def makeShuffleHistory(self):
         self.r.p.cycleLength = cycle
         self.r.core[0].p.chargeTime = 3
 
+        # add some fake missing parameter data to test allowMissing
+        self.db.h5db["c00n00/Reactor/missingParam"] = "i don't exist"
+
     def _compareArrays(self, ref, src):
         """
         Compare two numpy arrays.
@@ -194,6 +197,16 @@ def test_computeParents(self):
             database3.Layout.computeAncestors(serialNums, numChildren, 3), expected_3
         )
 
+    def test_load(self) -> None:
+        self.makeShuffleHistory()
+        with self.assertRaises(KeyError):
+            _r = self.db.load(0, 0)
+
+        _r = self.db.load(0, 0, allowMissing=True)
+
+        del self.db.h5db["c00n00/Reactor/missingParam"]
+        _r = self.db.load(0, 0, allowMissing=False)
+
     def test_history(self) -> None:
         self.makeShuffleHistory()