Expand on error descriptions

contentcuration/contentcuration/constants/completion_criteria.py

@@ -1,6 +1,5 @@
 from django.core.exceptions import ValidationError
 from jsonschema import RefResolver
-from jsonschema.exceptions import best_match
 from jsonschema.validators import validator_for
 from le_utils.constants import completion_criteria
 from le_utils.constants import content_kinds
@@ -31,9 +30,24 @@ def validate(data, kind=None):
     if isinstance(data, (dict,)) and not data:
         return
 
-    error = best_match(validator.iter_errors(data))
-    if error is not None:
-        raise ValidationError("Completion criteria does not conform to schema") from error
+    error_descriptions = []
+    # @see https://python-jsonschema.readthedocs.io/en/latest/errors/
+    for error in validator.iter_errors(data):
+        if error.cause:
+            # documentation says this will only be set on FormatChecker errors
+            error_descriptions.append(error.cause)
+        elif error.absolute_path:
+            # if there's a path to a field, we can give a specific error
+            json_path = ".".join(error.absolute_path)
+            error_descriptions.append(ValidationError("{} {}".format(json_path, error.message)))
+        else:
+            # without a path, likely top-level validation error, e.g. `anyOf` conditions
+            error_descriptions.append(ValidationError("object doesn't satisfy '{}' conditions".format(error.validator)))
+
+    if error_descriptions:
+        e = ValidationError("Completion criteria doesn't conform to schema")
+        e.error_list.extend(error_descriptions)
+        raise e
 
     model = data.get("model")
     if kind is None or model is None:

contentcuration/contentcuration/tests/test_completion_criteria.py

@@ -2,6 +2,7 @@
 from django.test import SimpleTestCase
 from le_utils.constants import completion_criteria
 from le_utils.constants import content_kinds
+from le_utils.constants import mastery_criteria
 
 from contentcuration.constants.completion_criteria import validate
 
@@ -13,12 +14,16 @@ def test_validate__success(self):
     def test_validate__success__empty(self):
         validate({})
 
-    def test_validate__fail(self):
-        with self.assertRaises(ValidationError):
+    def test_validate__fail__model(self):
+        with self.assertRaisesRegex(ValidationError, "model 'does not exist' is not one of"):
             validate({"model": "does not exist"})
 
+    def test_validate__fail__threshold(self):
+        with self.assertRaisesRegex(ValidationError, "object doesn't satisfy 'anyOf' conditions"):
+            validate({"model": completion_criteria.PAGES, "threshold": "not a number"})
+
     def test_validate__content_kind(self):
-        with self.assertRaises(ValidationError):
-            validate({"model": completion_criteria.PAGES}, kind=content_kinds.EXERCISE)
-        with self.assertRaises(ValidationError):
-            validate({"model": completion_criteria.MASTERY}, kind=content_kinds.DOCUMENT)
+        with self.assertRaisesRegex(ValidationError, "is invalid for content kind"):
+            validate({"model": completion_criteria.PAGES, "threshold": 1}, kind=content_kinds.EXERCISE)
+        with self.assertRaisesRegex(ValidationError, "is invalid for content kind"):
+            validate({"model": completion_criteria.MASTERY, "threshold": {"mastery_model": mastery_criteria.DO_ALL}}, kind=content_kinds.DOCUMENT)