Password is not strong enough failures

Add a method to generate password with
1: use of both upper- and lower-case letters (case sensitivity)
2: inclusion of one or more numerical digits
3: inclusion of special characters, e.g. @, #, $ etc.
4: at least 15 characters in length

Closes-Bug: 1448217

Change-Id: I86bf157f1bdb44f5fc579dc5317784fe31df8521

tempest_lib/common/utils/data_utils.py

@@ -16,6 +16,7 @@
 import itertools
 import netaddr
 import random
+import string
 import uuid
 
 
@@ -56,6 +57,28 @@ def rand_name(name='', prefix=None):
     return rand_name
 
 
+def rand_password(length=15):
+    """Generate a random password
+
+    :param int length: The length of password that you expect to set
+    :return: a random password. The format is
+             '<random upper letter>-<random number>-<random special character>
+              -<random ascii letters or digit characters or special symbols>'
+             (e.g. 'G2*ac8&lKFFgh%2')
+    :rtype: string
+    """
+    upper = random.choice(string.ascii_uppercase)
+    ascii_char = string.ascii_letters
+    digits = string.digits
+    digit = random.choice(string.digits)
+    puncs = '~!@#$%^&*_=+'
+    punc = random.choice(puncs)
+    seed = ascii_char + digits + puncs
+    pre = upper + digit + punc
+    password = pre + ''.join(random.choice(seed) for x in range(length - 3))
+    return password
+
+
 def rand_url():
     """Generate a random url that inclues a random number
 

tempest_lib/tests/common/utils/test_data_utils.py

@@ -56,6 +56,20 @@ class TestDataUtils(base.TestCase):
         actual2 = data_utils.rand_name(prefix='prefix-str')
         self.assertNotEqual(actual, actual2)
 
+    def test_rand_password(self):
+        actual = data_utils.rand_password()
+        self.assertIsInstance(actual, str)
+        self.assertRegexpMatches(actual, "[A-Za-z0-9~!@#$%^&*_=+]{15,}")
+        actual2 = data_utils.rand_password()
+        self.assertNotEqual(actual, actual2)
+
+    def test_rand_password_with_len(self):
+        actual = data_utils.rand_password(8)
+        self.assertIsInstance(actual, str)
+        self.assertRegexpMatches(actual, "[A-Za-z0-9~!@#$%^&*_=+]{8}")
+        actual2 = data_utils.rand_password(8)
+        self.assertNotEqual(actual, actual2)
+
     def test_rand_url(self):
         actual = data_utils.rand_url()
         self.assertIsInstance(actual, str)