AWS Lambda

It is an serverless compute unit. Allows to run code without provisioning or managing servers
Automated version of EC2 (Elastic Cloud Compute). No need to worry about underlying architecture
Upload the code and Lambda will take care of everything required to run the application
Cannot be used for deploying application. Used for running background tasks

Triggers

Services That Lambda Reads From
Services That Invoke Lambda Functions Synchronously
Services That Invoke Lambda Functions Asynchronously

Execution Role

Allows it to access AWS services and resources

Layers

Addition code that can be added into Lambda. It’s in the form of Zip files that contains additional libraries, functions
Max size of uncompressed Zip: 250 MB

Environment Variables

Dynamically pass settings to function code and library without making any changes in code
They are represent as key-value pair

import json
import boto3
 
def lambda_handler(event, context):
	bucket_name = 'lti871'
	object_name = '/covid_data/cases.csv'
 
	s3 = boto3.client("s3")
	file_obj = s3.get_object(Bucket=bucket_name, Key=object_name)
	file_content = file_obj["Body"].read().decode("utf-8").strip()
	lines = file_content.split('n')
 
	split_lines = []
	for line in lines:
		columns = line.split(",")
		split_lines.append(columns)
 
	dynamo_db = boto3.resource('dynamodb')
	dynamoTable = dynamo_db.Table('covid_data')
 
	for line in split_lines:
		dynamoTable.put_item(
			Item = {
				'province_state': int(line[0]),
				'country_region': line[1],
				'last_update' : string(line[2]),
				'latitude' : float(line[3]),
				'longitude' : float(line[4]),
				'confirmed' : int(ines[5]),
				'deaths' : int(line[6]),
				'recovered' : int(line[7]),
				'active' : int(line[8])
			}
		)