diff --git a/awx/api/serializers.py b/awx/api/serializers.py
index 35d6c2348a..b373e492d7 100644
--- a/awx/api/serializers.py
+++ b/awx/api/serializers.py
@@ -40,6 +40,7 @@ from awx.main.models import * # noqa
 from awx.main.access import get_user_capabilities
 from awx.main.fields import ImplicitRoleField
 from awx.main.utils import get_type_for_model, get_model_for_type, build_url, timestamp_apiformat, camelcase_to_underscore, getattrd
+from awx.main.validators import vars_validate_or_raise
 
 from awx.conf.license import feature_enabled
 from awx.api.fields import BooleanNullField, CharNullField, ChoiceNullField, EncryptedPasswordField, VerbatimField
@@ -110,20 +111,6 @@ def reverse_gfk(content_object):
         camelcase_to_underscore(content_object.__class__.__name__): content_object.get_absolute_url()
     }
 
-def vars_validate_or_raise(vars_str):
-    # vars must be blank, a valid JSON or YAML dict, or ...
-    try:
-        json.loads((vars_str or '').strip() or '{}')
-        return vars_str
-    except ValueError:
-        pass
-    try:
-        yaml.safe_load(vars_str)
-        return vars_str
-    except yaml.YAMLError:
-        pass
-    raise serializers.ValidationError('Must be valid JSON or YAML.')
-
 
 class BaseSerializerMetaclass(serializers.SerializerMetaclass):
     '''
diff --git a/awx/main/validators.py b/awx/main/validators.py
index ca7c851772..438fb98bcd 100644
--- a/awx/main/validators.py
+++ b/awx/main/validators.py
@@ -4,11 +4,16 @@
 # Python
 import base64
 import re
+import yaml
+import json
 
 # Django
 from django.utils.translation import ugettext_lazy as _
 from django.core.exceptions import ValidationError
 
+# REST framework
+from rest_framework.serializers import ValidationError as RestValidationError
+
 
 def validate_pem(data, min_keys=0, max_keys=None, min_certs=0, max_certs=None):
     """
@@ -166,3 +171,21 @@ def validate_ssh_private_key(data):
     credential.
     """
     return validate_pem(data, min_keys=1)
+
+def vars_validate_or_raise(vars_str):
+    """
+    Validate that fields like extra_vars or variables on resources like
+    job templates, inventories, or hosts are either an acceptable
+    blank string, or are valid JSON or YAML dict
+    """
+    try:
+        json.loads((vars_str or '').strip() or '{}')
+        return vars_str
+    except ValueError:
+        pass
+    try:
+        yaml.safe_load(vars_str)
+        return vars_str
+    except yaml.YAMLError:
+        pass
+    raise RestValidationError('Must be valid JSON or YAML.')