Shortly after the last video CloudFormation Templates and jq Tips, I wanted to know what the required parameters in a CloudFormation template were. This is also an easy task with jq. I’ll show you how to use jq to quickly summarize the required and optional parameters in a CloudFormation template in this post. It’s a one-liner 😁

First, we’ll download a sample template:

wget "https://s3.amazonaws.com/cloudformation-templates-us-east-1/EC2InstanceWithSecurityGroupSample.template"
mv EC2InstanceWithSecurityGroupSample.template ec2.json

To list the required parameters:

$ cat ec2.json | jq -r '.Parameters | to_entries | .[] | select(.value.Default == null) | .key'
KeyName

To list the optional parameters:

$ cat ec2.json | jq -r '.Parameters | to_entries | .[] | select(.value.Default != null) | .key'
InstanceType
SSHLocation

Hope you found this helpful. 🎉 This is also even shorter and sweeter with lono inspect summary.

Related Posts:

• Summarize CloudFormation Required Parameters with jq
• Summarize CloudFormation Resources with jq Tip
• Lono Xgraph Tutorial Introduction - Visualizing the Dependency Graph
• Lono Summary Tutorial Introduction - Summarize CloudFormation Template