The AWS Serverless Application Model (AWS SAM) transform is a AWS CloudFormation macro that transforms SAM templates into CloudFormation templates.
To use the SAM transform, add AWS::Serverless-2016-10-31
to the Transform
section of your CloudFormation template.
Benefits of using the SAM transform include:
- Built-in best practices and sane defaults.
- Local testing and debugging with the AWS SAM CLI.
- Extension of the CloudFormation template syntax.
Save the following as template.yaml
:
Transform: AWS::Serverless-2016-10-31
Resources:
MyFunction:
Type: AWS::Serverless::Function
Properties:
Runtime: nodejs18.x
Handler: index.handler
InlineCode: |
exports.handler = async (event) => {
console.log(event);
}
And deploy it with the SAM CLI:
sam sync --stack-name sam-app
The AWS::Serverless::Function
resource will create a AWS Lambda function that logs events it receives.
Under the hood, the template is transformed into the JSON equivalent of the following CloudFormation template:
Resources:
MyFunction:
Type: AWS::Lambda::Function
Properties:
Code:
ZipFile: |
exports.handler = async (event) => {
console.log(event);
}
Handler: index.handler
Role: !GetAtt MyFunctionRole.Arn
Runtime: nodejs18.x
Tags:
- Key: lambda:createdBy
Value: SAM
MyFunctionRole:
Type: AWS::IAM::Role
Properties:
AssumeRolePolicyDocument:
Version: "2012-10-17"
Statement:
- Action:
- sts:AssumeRole
Effect: Allow
Principal:
Service:
- lambda.amazonaws.com
ManagedPolicyArns:
- arn:aws:iam::aws:policy/service-role/AWSLambdaBasicExecutionRole
Tags:
- Key: lambda:createdBy
Value: SAM
For a more thorough introduction, see the this tutorial in the Developer Guide.
You'll need to have Python 3.8 installed.
Create a virtual environment:
python3 -m venv .venv
source .venv/bin/activate
Set up dependencies:
make init
Run tests:
make pr
See DEVELOPMENT_GUIDE.md
for further development instructions, and CONTRIBUTING.md
for the contributing guidelines.
The best way to interact with the team is through GitHub. You can either create an issue or start a discussion.
You can also join the #samdev
channel on Slack.