support "UserName" attribute for AWS::IAM::User, as per http://docs.a…

…ws.amazon.com/AWSCloudFormation/latest/UserGuide/aws-properties-iam-user.html#cfn-iam-user-username (cloudtools#529)

troposphere/iam.py

@@ -5,7 +5,7 @@
 
 from . import AWSObject, AWSProperty
 from .validators import integer, boolean, status
-from .validators import iam_path, iam_role_name, iam_group_name
+from .validators import iam_path, iam_role_name, iam_group_name, iam_user_name
 
 try:
     from awacs.aws import Policy
@@ -103,6 +103,7 @@ class User(AWSObject):
         'ManagedPolicyArns': ([basestring], False),
         'LoginProfile': (LoginProfile, False),
         'Policies': ([Policy], False),
+        'UserName': (iam_user_name, False),
     }
 
 

troposphere/validators.py

@@ -95,6 +95,20 @@ def iam_names(b):
         raise ValueError("%s is not a valid iam name" % b)
 
 
+def iam_user_name(user_name):
+    if len(user_name) > 64:
+        raise ValueError(
+            "AWS::IAM::User property 'UserName' may not exceed 64 characters")
+
+    iam_user_name_re = compile(r'^[\w+=,.@-]+$')
+    if iam_user_name_re.match(user_name):
+        return user_name
+    else:
+        raise ValueError(
+            "%s is not a valid value for AWS::IAM::User property 'UserName'",
+            user_name)
+
+
 def iam_path(path):
     if len(path) > 512:
         raise ValueError('IAM path %s may not exceed 512 characters', path)