L2 [Exercise] AWS Lambda

1、Requirement : Order history app

2、Create IAM role enable AWS Lambda

Policies

• Read only access from Kinesis
• DynamoDB Full Access

3、AWS Lambda Function

• Runtime: python 3.6
• Excuting role: existing role

3-1 Add Lambda trigger

3-2 Runtime code

lambda_function.py

import base64
import json
import boto3
import decimal

def lambda_handler(event, context):
    item = None
    dynamo_db = boto3.resource('dynamodb')
    table = dynamo_db.Table('CadabraOrders')
    decoded_record_data = [base64.b64decode(record['kinesis']['data']) for record in event['Records']]
    deserialized_data = [json.loads(decoded_record) for decoded_record in decoded_record_data]

    with table.batch_writer() as batch_writer:
        for item in deserialized_data:
            invoice = item['InvoiceNo']
            customer = int(item['Customer'])
            orderDate = item['InvoiceDate']
            quantity = item['Quantity']
            description = item['Description']
            unitPrice = item['UnitPrice']
            country = item['Country'].rstrip()
            stockCode = item['StockCode']

            # Construct a unique sort key for this line item
            orderID = invoice + "-" + stockCode

            batch_writer.put_item(                        
                Item = {
                                'CustomerID': decimal.Decimal(customer),
                                'OrderID': orderID,
                                'OrderDate': orderDate,
                                'Quantity': decimal.Decimal(quantity),
                                'UnitPrice': decimal.Decimal(unitPrice),
                                'Description': description,
                                'Country': country
                        }
            )

3-3 Generate Log

./LogGenerator.py 10