I am going to point you to a few resources to help you standup a hello world serverless app using AWS Lambda using AWS Serverless Application Model (SAM).

Serverless is an architecture style, where you leverage a service offering without having to provision or manage underlying infrastructure; and benefit from the service automatically scaling to your needs.

Serverless app platforms (like AWS Lambda or other similar FaaS services) are a particular type of Serverless offering that can take your code, host it in an execution environment and make it available as a (scalable) runtime service to your consumers.

Some Reading & Setup

1. More details on Serverless – Read up https://aws.amazon.com/serverless/
2. What is SAM?
   • The AWS Serverless Application Model (AWS SAM) is an open-source framework that you can use to build serverless applications on AWS. – (from AWS site)
   • Read up https://docs.aws.amazon.com/serverless-application-model/latest/developerguide/what-is-sam.html
   • SAM consists of
     • AWS SAM Template – specification to define your serverless application
     • AWS SAM CLI – command line tool to build serverless applications that are defined by AWS SAM templates
   • SAM integrates with the rest of the AWS ecosystem, thus relieving you off other mundane activities.
3. Install SAM CLI
   • Please have an AWS Account created (with free tier ideally)
   • Install Docker so we can run the serverless applications locally (useful during development)
   • Refer  https://docs.aws.amazon.com/serverless-application-model/latest/developerguide/serverless-sam-cli-install-mac.html
4. Setup AWS Credentials – https://docs.aws.amazon.com/serverless-application-model/latest/developerguide/serverless-getting-started-set-up-credentials.html

The Hello World app itself

To get a sample hello world app running follow https://docs.aws.amazon.com/serverless-application-model/latest/developerguide/serverless-getting-started-hello-world.html

• • sam init – stands-up a simple hello world app with an AWS SAM template
  • sam build – to build the project and generate deployment artifacts
  • sam local invoke – to run the code once locally within a docker container
  • sam local start-api – brings up your code in a hosted http server
  • sam package – uploads deployment artifacts to S3
  • sam deploy – deploys the application using Cloudformation changesets

The example application implements a customary hello world application that is a Lambda function and is fronted by an API Gateway.

Run locally

• • sam build (to build the code)
  • sam invoke local (to perform one-off invocations)
  • sam local start-api (to run a local http server that runs your code)

Screenshots here…

To run on AWS Cloud

• sam deploy –guided