Serverless
Framework
Amazon AWS Lambda

Definition:
Build auto-scaling, pay-per-execution, event-driven apps on AWS Lambda


no charges if never called

Framework
comand line tool written in node.js
is multi-language and can be
used to deploy: python, java etc.

Installation

  • make sure you have node.js V6.6.0 installed


    (to check it run: node -v)


  • run: npm install serverless -g


  • make a directory for your first serverless project


    (run: mkdir restapi && cd restapi)


  • run the template creator


    (run: serverless create -t aws-node.js > it creates a scaffold of your project)


  • to deploy it (make sure you hava AWS credetials)


    then run: serverless deploy -r us-east-1 dev


    then run: serverless deploy

Project structure

  • handler.js
  • event.json
  • serverless-yml

handler.js

  • contains the code of your functions

event.json

  • whrere you keep your test data to trigger your functions

serverless.yml (most important file)

  • defines your project functions and the events who triggers them.
  • additionally you can define other infrastructure resources for you to use
    with your functions like AWS dynamo, AWS Bucket and more. this yml takes it all
    and deploys it as single unit. the serverless framework does it all behind the scenes for us.

Once updated project

  • Use serverless deploy function -f hello
    (it will just update your function)
  • we can log with:
    serverless logs -f hello -t

Help
serverless.com/framework/docs
chat.serverless.com

Why use it?

The Serverless Framework is a core component of The Coca-Cola Company's initiative to reduce IT operational costs and deploy services faster
- Patrick Brandt, Solution Arquitect

Diving deeper

Function
independent unit of deployment
like a microservice. It is merely code deployed in the cloud, that is most often written to perform a single job such as:

  • saving a user to the database
  • processing a file in a database
  • performing a scheduled task

Events
anything that triggers the functions. Events are:

  • endpoint (e.g. REST API)
  • AWS bucket upload (e.g. image)
  • CloudWatch timer (e.g. run every 5 minutes)
  • AWS SNS (e.g. a message)
  • CloudWatch alert (e.g. something happened)
  • and more...

Cool
When you create an event, the framework will automatically create the necessary infrastructure for that event and configure your function to listen for it.

Resources
are AWS infrastructure components that your function uses such as:


  • An AWS DynamoDB Table (e.g., for saving Users/Posts/Comments data)
  • An AWS S3 Bucket (e.g., for saving images or files)
  • An AWS SNS Topic (e.g., for sending messages asynchronously)
  • Anything that can be defined in CloudFormation is supported by the Serverless Framework

Services
It's where you define your functions,
events that trigger them, resources
your function use. serverless.yml