Ensuring we throw an error on bad YAML files (#1358)

The goal is to throw an error when there is a duplicate
key in the YAML file. Though if the key is heavily
nested, deep in the YAML file, sometimes our YAML
libraries will miss it.

armi/nucDirectory/nuclideBases.py

@@ -1082,6 +1082,7 @@ def imposeBurnChain(burnChainStream):
         return
     burnChainImposed = True
     yaml = YAML(typ="rt")
+    yaml.allow_duplicate_keys = False
     burnData = yaml.load(burnChainStream)
 
     for nucName, burnInfo in burnData.items():

armi/reactor/blueprints/tests/test_blueprints.py

@@ -199,6 +199,25 @@ class TestBlueprintsSchema(unittest.TestCase):
             2 2 2 2 2
 """
 
+    def test_noDuplicateKeysInYamlBlueprints(self):
+        """
+        Prove that if you duplicate a section of a YAML blueprint file,
+        a hard error will be thrown.
+        """
+        # loop through a few different sections, to test blueprints broadly
+        sections = ["blocks:", "components:", "component groups:"]
+        for sectionName in sections:
+            # modify blueprint YAML to duplicate this section
+            yamlString = str(self._yamlString)
+            i = yamlString.find(sectionName)
+            lenSection = yamlString[i:].find("\n\n")
+            section = yamlString[i : i + lenSection]
+            yamlString = yamlString[:i] + section + yamlString[i : i + lenSection]
+
+            # validate that this is now an invalid YAML blueprint
+            with self.assertRaises(Exception):
+                _design = blueprints.Blueprints.load(yamlString)
+
     def test_assemblyParameters(self):
         cs = settings.Settings()
         design = blueprints.Blueprints.load(self._yamlString)

armi/reactor/systemLayoutInput.py

@@ -275,6 +275,7 @@ def _readYaml(self, stream):
         consistent inputs.
         """
         yaml = YAML()
+        yaml.allow_duplicate_keys = False
         tree = yaml.load(stream)
         tree = INPUT_SCHEMA(tree)
         self.assemTypeByIndices.clear()

armi/settings/caseSettings.py

@@ -12,7 +12,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-r"""
+"""
 This defines a Settings object that acts mostly like a dictionary. It
 is meant to be treated mostly like a singleton, where each custom ARMI
 object has access to it. It contains global user settings like the core
@@ -22,7 +22,7 @@
 A settings object can be saved as or loaded from an YAML file. The ARMI GUI is designed to
 create this settings file, which is then loaded by an ARMI process on the cluster.
 
-A primary case settings is created as ``masterCs``
+A primary case settings is created as ``masterCs``.
 """
 import io
 import logging
@@ -401,6 +401,7 @@ def getSettingsSetByUser(self, fPath):
         # from the settings file to know which settings are user-defined
         with open(fPath, "r") as stream:
             yaml = YAML()
+            yaml.allow_duplicate_keys = False
             tree = yaml.load(stream)
             userSettings = tree[settingsIO.Roots.CUSTOM]
 

armi/settings/settingsIO.py

@@ -208,6 +208,7 @@ def _readYaml(self, stream):
         from armi.settings.fwSettings.globalSettings import CONF_VERSIONS
 
         yaml = YAML(typ="rt")
+        yaml.allow_duplicate_keys = False
         tree = yaml.load(stream)
         if "settings" not in tree:
             raise InvalidSettingsFileError(

armi/settings/tests/test_settingsIO.py

@@ -22,6 +22,7 @@
 from armi.cli import entryPoint
 from armi.settings import setting
 from armi.settings import settingsIO
+from armi.tests import TEST_ROOT
 from armi.utils import directoryChangers
 from armi.utils.customExceptions import (
     InvalidSettingsFileError,
@@ -68,6 +69,20 @@ def test_basicSettingsReader(self):
         self.assertFalse(getattr(reader, "filelessBP"))
         self.assertEqual(getattr(reader, "path"), "")
 
+    def test_readFromFile(self):
+        with directoryChangers.TemporaryDirectoryChanger():
+            inPath = os.path.join(TEST_ROOT, "armiRun.yaml")
+            outPath = "test_readFromFile.yaml"
+
+            txt = open(inPath, "r").read()
+            verb = "branchVerbosity:"
+            txt0, txt1 = txt.split(verb)
+            newTxt = f"{txt0}{verb} fake\n  {verb}{txt1}"
+            open(outPath, "w").write(newTxt)
+
+            with self.assertRaises(InvalidSettingsFileError):
+                settings.caseSettings.Settings(outPath)
+
 
 class SettingsRenameTests(unittest.TestCase):
     testSettings = [