Coerce boolean properties automatically

for values like "true", "F", or 1

stix2/properties.py

@@ -115,12 +115,31 @@ class IDProperty(Property):
 
 
 class BooleanProperty(Property):
-    # TODO:  Consider coercing some values (like the strings "true" and "false")
+
+    def clean(self, value):
+        if isinstance(value, bool):
+            return value
+
+        trues = ['true', 't']
+        falses = ['false', 'f']
+        try:
+            if value.lower() in trues:
+                return True
+            if value.lower() in falses:
+                return False
+        except AttributeError:
+            if value == 1:
+                return True
+            if value == 0:
+                return False
+
+        raise ValueError("not a coercible boolean value.")
 
     def validate(self, value):
-        if not isinstance(value, bool):
+        try:
+            return self.clean(value)
+        except ValueError:
             raise ValueError("must be a boolean value.")
-        return value
 
 
 REF_REGEX = re.compile("^[a-z][a-z-]+[a-z]--[0-9a-fA-F]{8}-[0-9a-fA-F]{4}"

stix2/test/test_indicator.py

@@ -101,7 +101,7 @@ def test_indicator_created_ref_invalid_format():
 
 def test_indicator_revoked_invalid():
     with pytest.raises(ValueError) as excinfo:
-        stix2.Indicator(revoked='false', **INDICATOR_KWARGS)
+        stix2.Indicator(revoked='no', **INDICATOR_KWARGS)
     assert str(excinfo.value) == "Invalid value for Indicator 'revoked': must be a boolean value."
 
 

stix2/test/test_properties.py

@@ -78,7 +78,19 @@ def test_boolean_property():
 
     assert bool_prop.validate(True) is not None
     assert bool_prop.validate(False) is not None
-    for invalid in ('true', 'false', "T", "F", 1, 0):
+    assert bool_prop.validate('True') is not None
+    assert bool_prop.validate('False') is not None
+    assert bool_prop.validate('true') is not None
+    assert bool_prop.validate('false') is not None
+    assert bool_prop.validate('TRUE') is not None
+    assert bool_prop.validate('FALSE') is not None
+    assert bool_prop.validate('T') is not None
+    assert bool_prop.validate('F') is not None
+    assert bool_prop.validate('t') is not None
+    assert bool_prop.validate('f') is not None
+    assert bool_prop.validate(1) is not None
+    assert bool_prop.validate(0) is not None
+    for invalid in ('abc', ['false'], {'true': 'true'}, 2, -1):
         print(invalid)
         with pytest.raises(ValueError):
             bool_prop.validate(invalid)