add a Makefile command to estimate infrastructure costs

[bernard357]

What is this?

This is a new CLI command added to the SPA project to estimate the cost of SPA deployment. When you type the command make cost-estimation this generates a CloudFormation template and passes it to the AWS CLI command estimate-template-cost. The output is a link to the AWS Calculator with cost indication for resources in the template.

Learn more:

• https://docs.aws.amazon.com/cli/latest/reference/cloudformation/estimate-template-cost.html

Why is this important?

While SPA is based on serverless AWS products and services, and very cost-effective, we need to factually estimate costs that it can incur.

How to implement it?

The AWS CLI has a command to bridge with the AWS Cost Calculator

Definition of Done

• Add to Makefile a new target cost-estimation with appropriate shell commands
• send temporary template to a S3 bucket

[bernard357]

Feb-17: make command has been implemented. However, the template generated by CDK for SPA is too big for the AWS CLI command. The template should be uploaded to a S3 bucket instead.