aws-lambda-step-by-step

guide to work with aws lambdas and it best practices

create a lambda - sam init

sam init --runtime python3.7 --dependency-manager pip --app-template hello-world --name sample_lambda

https://docs.aws.amazon.com/serverless-application-model/latest/developerguide/sam-cli-command-reference-sam-init.html

create an input event for your lambda - sam local generate event

# Generate the event that S3 sends to your Lambda function when a new object is uploaded
sam local generate-event s3 [put/delete]

# Generate the event that SQS sends to your Lambda function when something is sended to the queue
sam local generate-event sqs [put/delete]

https://docs.aws.amazon.com/serverless-application-model/latest/developerguide/sam-cli-command-reference-sam-local-generate-event.html

create a file with environment variables - local.env.json

{
  "MyFunction1": {
    "TABLE_NAME": "localtable",
    "BUCKET_NAME": "testBucket"
  },
  "MyFunction2": {
    "TABLE_NAME": "localtable",
    "STAGE": "dev"
  },
}

https://docs.aws.amazon.com/serverless-application-model/latest/developerguide/serverless-sam-cli-using-invoke.html#serverless-sam-cli-using-invoke-environment-file

build the lambda - sam build

# To build on your workstation, run this command in folder containing SAM template. Built artifacts will be written to .aws-sam/build folder
sam build

# To build inside a AWS Lambda like Docker container
sam build --use-container

https://docs.aws.amazon.com/serverless-application-model/latest/developerguide/sam-cli-command-reference-sam-build.html

run the lambda - sam local invoke

sam local invoke --event events/event.json --env-vars local.env.json 

https://docs.aws.amazon.com/serverless-application-model/latest/developerguide/sam-cli-command-reference-sam-local-invoke.html

run the lambda with a gateway - sam local start-api

sam local start-api --env-vars local.env.json

https://docs.aws.amazon.com/serverless-application-model/latest/developerguide/sam-cli-command-reference-sam-local-start-api.html

validate your template.yml - sam validate

sam validate template.yml

https://docs.aws.amazon.com/serverless-application-model/latest/developerguide/sam-cli-command-reference-sam-validate.html

pack your lambda - sam package

sam package --template-file template.yml --output-template-file package.yml

https://docs.aws.amazon.com/serverless-application-model/latest/developerguide/sam-cli-command-reference-sam-package.html

send your lambda onto AWS Serverless Application Repository - sam publish

# To publish an application
sam publish --template packaged.yaml --region us-east-1

https://docs.aws.amazon.com/serverless-application-model/latest/developerguide/sam-cli-command-reference-sam-publish.html

deploy your lambda - sam deploy

sam deploy --guided

https://docs.aws.amazon.com/serverless-application-model/latest/developerguide/sam-cli-command-reference-sam-deploy.html