Cloud Formation Template
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CF Template gives easier way to create aws application/infrastructure creational/update templates.
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It allows us to define parameters
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Template can be shared with others to create the application/infra in any account.
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CF Templates can be called from CI/CD Engines like jenkins
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CF Template can be written for any service to create any resource.
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CF Templates can be written in
- JSON
- YAML
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Example Scenario: Create the following in AWS
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Evaluate the Scenario:
- Console: Creation is simple but repetition can be difficult
- CLI: Scripting might require some prior knowledge, but changes will be difficult to handle in repetition
- CF Template: Create is time consuming but repetition is effective and easy.
Cloud Formation Basics
- Template: JSON/YAML file which has resources, parameters etc
- Resource: Any thing which can be created in AWS
- Parameter: Input from user
- Output: result of execution of Template
- Stack: Stack is required for execution of Template.
Cloud Formation Syntax
- Refer Here for official docs
- Refer Here for template structure
- Refer Here for directdevops.blog reference.
- JSON Syntax
{
"AWSTemplateFormatVersion" : "version date",
"Description" : "JSON string",
"Metadata" : {
template metadata
},
"Parameters" : {
set of parameters
},
"Mappings" : {
set of mappings
},
"Conditions" : {
set of conditions
},
"Transform" : {
set of transforms
},
"Resources" : {
set of resources
},
"Outputs" : {
set of outputs
}
}
- Sample Minimal Template
{
"AWSTemplateFormatVersion" : "2010-09-09",
"Description" : "learning cf",
"Resources": {
}
}
Sample AWS CF Template for Creating S3 bucket
- Manually create a S3 bucket to understand the approach.
- Create a directory and create a json file in this with following content
{
"AWSTemplateFormatVersion" : "2010-09-09",
"Description" : "learning cf",
"Resources": {
}
}
- Now since we are supposed to create a s3 resource, google aws cloudformation s3 bucket
- Now click and open the aws docs which has the resource structure/syntax defined.
- The following content will be enough to create s3 bucket
{
"AWSTemplateFormatVersion" : "2010-09-09",
"Description" : "learning cf",
"Resources": {
"mys3": {
"Type" : "AWS::S3::Bucket",
"Properties": {
"BucketName": "qt-s3-learning-forcf.com"
}
}
}
}
- Now navigate to CLoudformation Service and Create stack by uploading the above template.
Dev Environment Setup
- From here Refer Setting up your machine for AWS CloudFormation section
