aws cloudformation intro

Manage, configure, and provision your AWS infrastructure as code.

Resources are defined using a CloudFormation template that is interpreted and creates appropriate API calls for the resources you've defined. * Supports JSON and YAML

Benefits of IaC/CloudFormation

Consistent - infrastructure is provisioned consistently with fewer mistakes
Quick and efficient - less time and effort that configuring things manually
Version control - you can version control and peer review templates
Free to use - the tooling is free to use, just pay for provisioned resources
Manage updates - can be used to manage updates and dependencies
Rolling back - you can rollb ack to a previous state and delete the entire stack as well

CloudFormation process

YAML or JSON template
S3 - after creating a template you upload it to CloudFormation using S3
API Calls - CloudFormation reads the template from S3 and executes API calls on your behalf
CloudFormation Stack - the resulting set of resources from a template

Example CloudFormation template:

CloudFormation has quite a few non-required fields, the only thing that is truly required are the resource declarations.

Note: There are quite a few template snippets that AWS provides for template examples.

Resources section is mandatory
The Transform section is for referencing additional code stored in S3, allowing

for code re-use (like Lambda or template snippets/reusable pieces of CloudFormation code)

Exam tips

IaC - allows you to manage, configure, and provision AWS infra as YAML or JSON
Parameters - input custom values
Conditions - provision resources based on things like environment
Resources - section is mandatory and describes resources to create
Mappings - create custom mappings like using a specific AMI for a given region
Transform - allows you to reference code or reusable snippets of CloudFormation code

in S3