README
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Rain Web App Sample
This application demonstrates advanced capabilities of AWS CloudFormation Rain, a CLI tool written in Go that uses the AWS SDK to improve the developer experience for authoring and deploying CloudFormation templates.
Rain allows you to create client-side modules in YAML, so that you can re-use
common patterns and speed up the development process. These modules look just
like regular CloudFormation templates and can be included in a parent template
using the !Rain::Module directive.
Rain also looks for special Metadata comments on the AWS::S3::Bucket resource
to run external build scripts before and after deployment, and then upload the
contents of a folder to the newly created bucket after deployment is complete.
This allows you to so things like build your web site and even fix its
configuration so that the web site knows the URL of the API Gateway, all in one
step without having to do multiple deployments.
For Lambda functions, Rain can run a script to build and/or package your handler, and then it will upload a zip file to an assets bucket before deploying the stack.
Combining these features together allows you to deploy an entire serverless web
application with a single command, in this case rain deploy -x webapp.yaml.
TODO: Architecture diagram
TODO: Sequence of operations
TODO: Template snippets
Directories