How do I use a CloudFormation output value in a script with Ansible - ansible

Question

I'm trying to set up some automation for a school project. The gist of it is:
Install an EC2 instance via CloudFormation. Then
Use cfn-init to
Install a very basic Ansible configuration
Download an Ansible playbook from S3
Run said playbook to install a Redshift cluster via CloudFormation
Install some necessary packages
Install some necessary Python modules
Download a Python script that will
Connect to the Redshift database
Create a table
Use the COPY command to import data into the table
It all works up to the point of executing the script. Doing so manually works a treat, but that is because I can copy the created Redshift endpoint into the script for the database connection. The issue I have is that I don't know how to extract that output value from CloudFormation so it can be inserted it into the script for a fully automated (save the initial EC2 deployment) solution.
I see that Ansible has at least one means of doing so (cloudformation_facts, for instance), but I'm a bit foggy on how to implement it. I've looked at examples but it hasn't become any clearer. Without context I'm lost and so far all I've seen are standalone snippets.

Answer 1

In order to ensure an answer is listed:
I figured out the describe-stacks and describe-stack-resources sub-commands to the aws cloudformation cli command. Using these, I was able to track down the information I needed. In particular, I needed to access a role. This is the command that I used:
aws cloudformation describe-stacks --stack-name=StackName --region=us-west-2 \
--query 'Stacks[0].Outputs[?OutputKey==`RedshiftClusterEndpointAddress`].OutputValue' \
--output text
I first used the describe-stacks subcommand to get a list of my stacks. The relevant stack is the first in the list (an array) so I used Stacks[0] at the top of my query for the describe-stack-recources subcommand. I then used Outputs since I am interested in a value from the CloudFormation output list. I know the name of the key (RedshiftClusterEndpointAddress), so I used that as the parameter. I then used OutputValue to return the value of RedshiftClusterEndpointAddress.