add --disable_email option

Author: michaelaberman

README.md

@@ -198,7 +198,8 @@ arguments:
                         accounts to the behavior graph. If the master account already has a behavior graph in a Region, then 
                         the member accounts are added to that behavior graph. If you do not provide a list of Regions, then
                         the script acts across all Regions that Detective supports.
-  
+  --disable_email       If this flag is included, then emails will not be sent to the member accounts. Member accounts must still accept 
+                        the invitation before they are added to the behavior graph.
 ```
 
 
@@ -237,3 +238,15 @@ arguments:
                         behavior graphs, the script disables Detective for the master account in all of the specified Regions.
                         When Detective is disabled for a master account, the master account's behavior graph is disabled.
 ```
+
+## Contributing to this project
+
+### Running tests
+
+```
+# Install requirements
+pip3 install boto3 pytest
+
+# In the tests/ directory...
+pytest -s
+```

enableDetective.py

@@ -57,6 +57,10 @@ def _master_account_type(val: str, pattern: str = r'[0-9]{12}'):
     parser.add_argument('--enabled_regions', type=str,
                         help=('Regions to enable Detective. If not specified, '
                               'all available regions enabled.'))
+    parser.add_argument('--disable_email', action='store_true',
+                        help=('Don\'t send emails to the member accounts. Member '
+                              'accounts must still accept the invitation before '
+                              'they are added to the behavior graph.'))
     return parser.parse_args(args)
 
 
@@ -228,7 +232,7 @@ def _master_memberList(g: str) -> typing.List[typing.Dict]:
             {g: {x['AccountId'] for x in v if x['Status'] == 'INVITED'} for g, v in pending})
 
 
-def create_members(d_client: botocore.client.BaseClient, graph_arn: str, account_ids: typing.Set[str],
+def create_members(d_client: botocore.client.BaseClient, graph_arn: str, disable_email: bool, account_ids: typing.Set[str],
                    account_csv: typing.Dict[str, str]) -> typing.Set[str]:
     """
     Creates member accounts for all accounts in the csv that are not present in the graph member set.
@@ -257,7 +261,8 @@ def create_members(d_client: botocore.client.BaseClient, graph_arn: str, account
                     for x in set_difference]
         response = d_client.create_members(GraphArn=graph_arn,
                                         Message='Automatically generated invitation',
-                                        Accounts=new_members)
+                                        Accounts=new_members,
+                                        DisableEmailNotification=disable_email)
         for error in response['UnprocessedAccounts']:
             logging.exception(f'Could not create member for account {error["AccountId"]} in '
                             f'graph {graph_arn}: {error["Reason"]}')
@@ -336,7 +341,7 @@ def enable_detective(d_client: botocore.client.BaseClient, region: str):
 
                 for graph, members in all_members.items():
                     new_accounts = create_members(
-                        d_client, graph, members, aws_account_dict)
+                        d_client, graph, args.disable_email, members, aws_account_dict)
                     print("Sleeping for 5s to allow new members' invitations to propagate.")
                     time.sleep(5)
                     accept_invitations(args.assume_role, itertools.chain(