Backend Java project (sam-rest-dynamodb-crud)

U-pamers Application (IT Marathon 3.0)

This project contains source code and supporting files for a serverless application that you can deploy with the SAM CLI.

The application uses several AWS resources, including Lambda functions and an API Gateway API. These resources are defined in the template.yaml file in this project. You can update the template to add AWS resources through the same deployment process that updates your application code.

If you prefer to use an integrated development environment (IDE) to build and test your application, you can use the AWS Toolkit.
The AWS Toolkit is an open source plug-in for popular IDEs that uses the SAM CLI to build and deploy serverless applications on AWS. The AWS Toolkit also adds a simplified step-through debugging experience for Lambda function code. See the following links to get started.

• CLion
• GoLand
• IntelliJ
• WebStorm
• Rider
• PhpStorm
• PyCharm
• RubyMine
• DataGrip
• VS Code
• Visual Studio

Deploy the sample application

The Serverless Application Model Command Line Interface (SAM CLI) is an extension of the AWS CLI that adds functionality for building and testing Lambda applications. It uses Docker to run your functions in an Amazon Linux environment that matches Lambda. It can also emulate your application's build environment and API.

To use the SAM CLI, you need the following tools.

• SAM CLI - Install the SAM CLI
• Java11 - Install the Java 11
• Maven - Install Maven
• Docker - Install Docker community edition

Create DynamoDb table

aws dynamodb create-table --cli-input-json file://create-tables/create-table.json

Build and deploy

To build and deploy your application for the first time, run the following in your shell:

sam build
sam deploy --guided

The first command will build the source of your application. The second command will package and deploy your application to AWS, with a series of prompts:

• Stack Name: The name of the stack to deploy to CloudFormation. This should be unique to your account and region, and a good starting point would be something matching your project name.
• AWS Region: The AWS region you want to deploy your app to.
• Confirm changes before deploy: If set to yes, any change sets will be shown to you before execution for manual review. If set to no, the AWS SAM CLI will automatically deploy application changes.
• Allow SAM CLI IAM role creation: Many AWS SAM templates, including this example, create AWS IAM roles required for the AWS Lambda function(s) included to access AWS services. By default, these are scoped down to minimum required permissions. To deploy an AWS CloudFormation stack which creates or modifies IAM roles, the CAPABILITY_IAM value for capabilities must be provided. If permission isn't provided through this prompt, to deploy this example you must explicitly pass --capabilities CAPABILITY_IAM to the sam deploy command.
• Save arguments to samconfig.toml: If set to yes, your choices will be saved to a configuration file inside the project, so that in the future you can just re-run sam deploy without parameters to deploy changes to your application.

You can find your API Gateway Endpoint URL in the output values displayed after deployment.

Cleanup

To delete the sample application that you created, use the AWS CLI. Assuming you used your project name for the stack name, you can run the following:

aws cloudformation delete-stack --stack-name dynamo-db-crud
aws dynamodb delete-table --table-name it-marathon-v3-user-db

Package layer and lambda functions manually

To deploy manually the common layer of the application and all lambda functions, you need to execute the next script in Linux shell

 ./package-layer-and-functions.sh

Manual Deployment

lambda-common-layer.zip - should be uploaded to AWS Lambda Layers function-GetUserList.zip - should be uploaded to AWS Lambda Functions function-GetUserListByQuery.zip - should be uploaded to AWS Lambda Functions function-CreateUser.zip - should be uploaded to AWS Lambda Functions function-DeleteUser.zip - should be uploaded to AWS Lambda Functions function-GetUser.zip - should be uploaded to AWS Lambda Functions function-UpdateUser.zip - should be uploaded to AWS Lambda Functions

Resources

See the AWS SAM developer guide for an introduction to SAM specification, the SAM CLI, and serverless application concepts.

Next, you can use AWS Serverless Application Repository to deploy ready to use Apps that go beyond hello world samples and learn how authors developed their applications: AWS Serverless Application Repository main page