我如何运行AWS Lambda函数以使我知道CloudFormation已完成整个堆栈的创建

Question

I would like to make an automated call to a custom program API as soon as CloudFormation has completed the entire stack creation (deployment of instances, setup of VPC, Puppet scripts, etc.).

What is the correct way to go about this?

After some research, it seems a good option would be to launch an AWS Lambda function triggered by the event that stack creation has been completed successfully, but I have no idea how to approach this.

Any ideas or advice would be appreciated.

Answer 1

You can provision and coordinate a lot of what you're talking about (setup of VPC, etc.) with CloudFormation, the DependsOn attribute and nested CloudFormation stacks. This way you can order the execution of the CloudFormation stacks so that, for example, your VPC is created first followed by launching your EC2 instance(s) followed by the deployment of the software on the instance(s).

You can also coordinate the execution of the other behavior you mentioned (deployment [on] instances, [calling] Puppet scripts, etc.) using AWS::CloudFormation::Init . This way, you can call out to your Puppet scripts from your EC2 instance within the CloudFormation template. The actual execution of your Puppet scripts occurs on the EC2 instance(s).

If you want to see an example of calling out to a configuration management tool from CloudFormation (in this case, we're using Chef Solo), see app-instance.json . If you'd like to see an example of using nested stacks, see dromedary-master.json .

There's also some examples of using Lambda on our blog as well (Stelligent), but it doesn't seem like you need to use Lambda in this case based on the problem you're trying to solve.

PS You don't have to use nested stacks either, but it can make things a little cleaner. But, you do want to control the creation order of the resources so the DependsOn attribute will help you in doing so.