Wolkenobergrenze
Automatischer Kostendeckel für Amazons Cloud-Server

c't 12/2018, S. 168
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ec2stoptagged.py     Kostendeckel (Python-2.7-Funktion für Amazon Lambda)
lambda-role          Role der Lambda-Funktion
topic-policy         Topic-Policy für Alarm-SNS

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Update Christian Schwabe 31.5.2018

The original Script use AWS Budgets to trigger events to stop tagged instances in all AWS regions.
Update of this Version to have a PoC for just the function with trigger through SNS.
No trigger with budget control!
Only for instances in Ireland region!

You need: 
- Tagged and unTagged EC2 Instances
- Lambda function (python script)
- Lambda role 
- Lambda TestEvent (just to test the lambda function)
- SNS Topic (Topic Name = Tag for the Instance)

How it works:
- Build and tag your instances
- Create Lambda function (python 2.7), create CustomRole, copy py script
- To test the Lambda function, test with TestEvent (comment return for every trigger in py script - row 22)
- Create topic for SNS with the name of the tagged instance to stop
- Create subscription for this topic, use AWS Lambda as protocol and the ARN from your Lambda function
- TEST!!!!
- Publish a message via SNS dashboard, use the ARN from your topic, as subject use "AutoShutDownTrigger", no matter what message
! If you change the subject of the message -> nothing will be stoped
! If your SNS topic name is not equal to the instance tag -> nothing will be stoped
! So it is possible to have one SNS topic for each tag you like to trigger