Small fixes to update-ami-accounts

bin/update-ami-accounts

@@ -17,7 +17,7 @@ Example 1: Let's just run a report of all AMIs matching '*Duane*' in all regions
 profile has access to.  Notice the wildcards in quotes so bash won't try to expand them
 out to filenames.
 
-[duane.e.waddle@DPS0591 bin]$ AWS_PROFILE=gov-common-services-terraformer ./duane.py '*Duane*'
+[duane.e.waddle@DPS0591 bin]$ AWS_PROFILE=gov-common-services-terraformer ./update-ami-accounts '*Duane*'
 Looking for AMIs matching "*Duane*" in the following regions:
     us-gov-east-1
     us-gov-west-1
@@ -31,7 +31,7 @@ us-gov-west-1  |ami-0ee37a86b09aefad0 |Duane_Testing_20201124233617
 
 Example 2: Regions can be specified with a list or wildcard.  This is just a report too:
 
-[duane.e.waddle@DPS0591 bin]$ AWS_PROFILE=gov-common-services-terraformer ./duane.py --region us-gov-east-1 --region '*west*' '*Duane*'
+[duane.e.waddle@DPS0591 bin]$ AWS_PROFILE=gov-common-services-terraformer ./update-ami-accounts --region us-gov-east-1 --region '*west*' '*Duane*'
 Looking for AMIs matching "*Duane*" in the following regions:
     us-gov-east-1
     us-gov-west-1
@@ -44,7 +44,7 @@ us-gov-west-1  |ami-0ee37a86b09aefad0 |Duane_Testing_20201124233617
 
 Example 3: If we list one or more accounts then sharing is updated
 
-[duane.e.waddle@DPS0591 bin]$ AWS_PROFILE=gov-common-services-terraformer ./duane.py --region '*1' '*Duane*' 738800754746 721817724804
+[duane.e.waddle@DPS0591 bin]$ AWS_PROFILE=gov-common-services-terraformer ./update-ami-accounts --region '*1' '*Duane*' 738800754746 721817724804
 Looking for AMIs matching "*Duane*" in the following regions:
  us-gov-east-1
  us-gov-west-1
@@ -62,7 +62,7 @@ us-gov-west-1  |ami-0ee37a86b09aefad0 |Duane_Testing_20201124233617            |
 Example 4: Sharing updates are atomic so if you could get a failure because
 one of several accounts you listed does not exist:
 
-[duane.e.waddle@DPS0591 bin]$ AWS_PROFILE=gov-common-services-terraformer ./duane.py --region '*1' '*Duane*' 738800754746 72181772480
+[duane.e.waddle@DPS0591 bin]$ AWS_PROFILE=gov-common-services-terraformer ./update-ami-accounts --region '*1' '*Duane*' 738800754746 72181772480
 Looking for AMIs matching "*Duane*" in the following regions:
  us-gov-east-1
  us-gov-west-1
@@ -83,6 +83,8 @@ message as to which one caused the error.  Maybe one day I'll improve that...
 """
 
 import argparse
+import re
+import sys
 import boto3
 import botocore
 from botocore.config import Config
@@ -196,8 +198,7 @@ def runmain(ami_filter,accounts,region_filters):
             else:
                 print(report_format.format(region,ami.get('ImageId'),ami.get('Name')))
 
-
-if __name__ == "__main__":
+def cli():
 
     parser = argparse.ArgumentParser()
     parser.add_argument('--region',action='append',required=False,
@@ -206,4 +207,24 @@ if __name__ == "__main__":
     parser.add_argument('accounts',nargs='*',help='list of AWS accounts to add AMIs to')
     args = parser.parse_args()
 
+    # Remove dashes from account IDs as a nice thing for user
+    args.accounts = [ f.replace("-","") for f in args.accounts ]
+
+    # AWS Accounts are 12 digits, all digits
+    invalid_accounts = []
+    digit_check = re.compile(r"^\d+$")
+    for account in args.accounts:
+        if len(account) != 12:
+            invalid_accounts.append("{0}: {1}".format(account,"Account length not 12"))
+        elif digit_check.fullmatch(account) is None:
+            invalid_accounts.append("{0}: {1}".format(account,"Account contains non-digit chars"))
+
+    if len(invalid_accounts) > 0:
+        for message in invalid_accounts:
+            print(message)
+        sys.exit(1)
+
     runmain(args.ami_filter,args.accounts,args.region)
+
+if __name__ == "__main__":
+    cli()