Task AWS: ApiGateway, Lambda, DynamoDB

At the end of this homework you need to have:

API Gateway with two endpoints to upload information about your products (id, name, picture URL, price) and to update information; Lambda that processes that upload (check if data is already present in DynamoDB and put it if it is not present); Lambda that processes information updates; DynamoDB with 1 Table with product information.

Implement small console application with generated API gateway sdk to create and update information (https://docs.aws.amazon.com/apigateway/latest/developerguide/how-to-call-apigateway-generated-java-sdk.html)

1. create DynamoDB table
2. create Lambda, use this code to it
3. create API Gateway
4. create a simple maven Java project

• 4.1 add dependencies:
  

• 4.1.1. include dependency aws-lambda-java-core .This library gives us two interfaces for handler method (requestHandler, RequestStreamHandler)
  

• 4.1.2. aws-java-sdk-dynamodb. This sdk library has the client classes that are used for communicating with DynamoDb service.
  

• 4.1.3 json-simple(for working with json objects)
  

• 4.1.4.gson(to create json string from java object and java object from json string)
  

• 4.1.5 build plugins:
  

•     * maven- compiler-plugin (to compile the source code  of maven project to executable program)
  

•     * maven-shade-plugin (to package the artifact in an uber-jar. Uber-jar is a jar that contains everything.
      It takes all the dependencies and puts them in a one big JAR)
  

• 4.2.create Product class which can be converted to json
• 4.3 create ProductLambdaHandler, which implements RequestStreamHandler, and override the method HandleRequest.

•    parameter InputStream includes all the incoming data(pathparameters, queryStringParameters, request body, request header)
  

•    parameter OutputStream is where we send or write the result.
  

•    parameter Context provides methods and properties that give info about invocation, function, execution environment etc