Serverless

• To deploy a Webapplication
• We need to develop web application on some programming language (C#, Java, python, nodejs, Ruby on Rails, PHP etc)
• Now to deploy this application we need
  • A physical or virtual machine with some OS
  • We need to install platform
  • We need some sort of webserver/middle ware to run our web application (Apache, Nginx, Tomat, IIS etc.)
  • Then we deploy our application code
    
• Serverless is a technology which helps in running function directly without worrying about the details of Which webserver/middleware. This is specifically called as Function as a Service.
• Operations/Functions in Serverless FaaS donot run all the time, they will be execution only when the request to it arrives and user will be charged based on whatever time code executed.
  
• In AWS Funtion as a Service (FaaS) is implemented by AWS lambda.
• Lets assume we need a compound interest calculator
• Lets create this in AWS Lambda
  
  
  
  
  
  
• Make changes in the code and deploy and create a test event
  
  
  
  
  
  
• Trigger is how your operation/function gets called
  
• Consider the below scenarios:
  • Every day at 9:00 pm i want to stop all the ec2 instances in the dev, test environments and start the ec2 instances at 8:00 am on all week days
  • Restart the ec2 instance by instance id
  • When a ticket is created in ITIL to create a vm then create an ec2 instance.