AWS Lambda → Basics

what is aws lambda →

Basically aws lambda simply called serverless computing or you just need to provide a code of your application to aws and aws itself manage everything in their end such as managing load on server,storage,type of instance etc….

It is a compute service thats lets you run code without provisoning or managing service

some important points →

1. Charge only for when code runs(counts when user hit to run the aplication) and bill count in miliseconds
2. Lambda function is simply means the code you provide to aws
3. Create multiple lambda function for high availablity; if one fail to run or 1 function is not enough(user is more than your counts of lambda function) you have an advantage to autoscale the lamda function
4. you can deploy your code here without managing it
5. aws lambda runs your code only when needed and you pay only for the compute time you consume no charge when your code is not running
6. All you need to do is supply your code in the form of one or more lamda function to aws lambda in one of the languages that it able to understand
7. It supports 7 languages till now

a. Python

b. Ruby

c. Go

d. c#

e. Java

f. Node Js

g. Powershell

8. you can’t enter in your instance where your code runs and nor custmized it

9. if you want to access your instance use EC2 not lambda

How Lambda works →

1. first you upload a code to lambda in one of the languages it supports
2. It executes the code on your behalf
3. After the code is invoked lambda automatically take care provisoning and managing the required server

Difference between AWS Lmabda and EC2 →

1. AWS Lambda is a platform as a service while EC2 is a Infrastructure as a service
2. Lamda supports only limited language while in EC2 instance you can run any code or language
3. In Lambda you only need to write the code but in ec2 you first need to chose the OS then install the software required and at last you push code in ec2
4. you can’t access your instance nor able to chose or custmized it but in EC2 you are able to choose variety of OS
5. Pay per miliseconds in lambda while in EC2 pay per seconds or hourly basic depend on the type of instance

Important Terms Used In Lamba →

1. Function → It simply means the code you provide to aws lambda that process events and have runtime that passes request and responses
2. Runtime →it allows to run your code in different languages …..the runtime sits between you and your code relaying invocation events,context info and responces between the two
3. Event →It is a JSON formatted document that contains the data for a function to process
4. Triggers →An AWS service as Amazon SNS or a custom service that triggers your function and executes its logic
5. Downstream Resource → an aws service such as s3 buckets etc that your lambda function calls once it is triggerd
6. Concurrency →No. of request your function serving in any given time limit → 1 code is run 1000 times (max)