diff --git a/test/python/WMCore_t/REST_t/Auth_t.py b/test/python/WMCore_t/REST_t/Auth_t.py
index 23c4da5ec68..975edaeacae 100644
--- a/test/python/WMCore_t/REST_t/Auth_t.py
+++ b/test/python/WMCore_t/REST_t/Auth_t.py
@@ -1,2 +1,85 @@
-from WMCore.REST.Auth import RESTAuth
-RESTAuth()
+"""
+Unit tests for REST/Auth.py module
+Author: Valentin Kuznetsov <vkuznet [AT] gmail [DOT] com>
+"""
+
+# system modules
+import os
+import json
+import logging
+import unittest
+
+# third party modules
+import cherrypy
+
+# WMCore modules
+from WMCore.REST.Auth import user_info_from_headers
+
+
+class RESTAuthTest(unittest.TestCase):
+    "Unit test for RESTAuth module"
+
+    def setUp(self):
+        """
+        setup necessary data for unit test usage
+        """
+        self.logger = logging.getLogger('rest_auth')
+
+        # REST/Auth.py module calculates checksum based on provided hmac
+        # for instnace for self.hmac we will expect self.chkSum
+        # with all CMS headers
+
+        # let's create set of different conditions
+        self.user_groups = []
+        self.hmacs = []
+        self.chkSums = []
+
+        # for group:users group:admin
+        user_groups = 'group:users group:admin'
+        hmac = '169d02b96265caf05894b526f99a22549dcd38ed'
+        chkSum = 'd357b299194ec4bed4e4fc73fc9ceab10139c16f'
+        self.user_groups.append(user_groups)
+        self.hmacs.append(hmac)
+        self.chkSums.append(chkSum)
+
+        # let's reverse order of user groups
+        user_groups = 'group:admin group:users'
+        self.user_groups.append(user_groups)
+        self.hmacs.append(hmac)
+        self.chkSums.append(chkSum)
+
+        # for group:admin group:users iam_group:test site:T1_XX_YYYY
+        user_groups = 'group:admin group:users iam_group:test site:T1_XX_YYYY'
+        hmac = '57ea0f58134aa079972da30a8fc2bf81853c949b'
+        chkSum = 'd357b299194ec4bed4e4fc73fc9ceab1013'
+        self.user_groups.append(user_groups)
+        self.hmacs.append(hmac)
+        self.chkSums.append(chkSum)
+
+    def testRESTAuth(self):
+        "test RESTAuth methods"
+        for idx in range(len(self.user_groups)):
+            user_groups = self.user_groups[idx]
+            hmac = self.hmacs[idx]
+            chkSum = self.chkSums[idx]
+
+            # for testing purposes we need to setup cherrypy headers
+            # cms-auth-status, cms-authn, cms-authz, cms-authn-hmac, cms-authn-name, cms-authn-dn
+            cherrypy.request.headers = {
+                'cms-auth-status': 'OK',
+                'cms-authn': 'fake',
+                'cms-authz-user': user_groups,
+                'cms-authn-hmac': hmac,
+                'cms-authn-name': 'test',
+                'cms-authn-dn': 'dn'}
+
+            authzKey = bytes(chkSum, 'UTF-8')
+            user = user_info_from_headers(key=authzKey)
+            self.logger.info("user_groups", user_groups)
+            self.logger.info("hmac", hmac)
+            self.logger.info("chkSum", chkSum)
+            self.logger.info("user", user)
+
+
+if __name__ == '__main__':
+    unittest.main()