CloudFormation template: reduce boilerplate code - aws-cloudformation

Question

I'm trying to compose CF template to deploy a serverless system consisting of several Lambdas. In my case, Lambda resource descriptions share a lot of properties; the only difference is filename and handler function.
How can I define something like common set of parameters in my template?
This boilerplate is awful:
LambdaCreateUser:
Type: AWS::Lambda::Function
Properties:
Code:
S3Bucket:
Ref: BucketForLambdas
S3Key: create_user.zip
Handler: create_user.lambda_handler
Runtime: python3.7
Role:
Fn::GetAtt: [ LambdaRole , "Arn" ]
Environment:
Variables: { "EnvTable": !Ref EnvironmentTable, "UsersTable": !Ref UsersTable }
LambdaDeleteUser:
Type: AWS::Lambda::Function
Properties:
Code:
S3Bucket:
Ref: BucketForLambdas
S3Key: delete_user.zip
Handler: delete_user.lambda_handler
Runtime: python3.7
Role:
Fn::GetAtt: [ LambdaRole , "Arn" ]
Environment:
Variables: { "EnvTable": !Ref EnvironmentTable, "UsersTable": !Ref UsersTable }

Answer 1

What you're looking for is AWS SAM which is a layer of syntactic sugar on top on CloudFormation. A basic representation of your template with AWS SAM would look like this:
AWSTemplateFormatVersion: '2010-09-09'
Transform: 'AWS::Serverless-2016-10-31'
Globals:
Function:
Runtime: python3.7
Environment:
Variables:
EnvTable: !Ref EnvironmentTable
UsersTable: !Ref UsersTable
Resources:
LambdaCreateUser:
Type: AWS::Serverless::Function
Properties:
Code:
S3Bucket:
Ref: BucketForLambdas
S3Key: create_user.zip
Handler: create_user.lambda_handler
Role: !GetAtt LambdaRole.Arn
LambdaDeleteUser:
Type: AWS::Serverless::Function
Properties:
Code:
S3Bucket:
Ref: BucketForLambdas
S3Key: delete_user.zip
Handler: delete_user.lambda_handler
Role: !GetAtt LambdaRole.Arn
But that's not the end. You can replace the code definition with a path to your code or even inline code and use sam build and sam package to build and upload your artifacts. You can also probably replace the role definition with SAM policy templates for further reduction of boilerplate code.