Pokemon API

Base URl: https://4q7ajbemgk.execute-api.us-east-2.amazonaws.com/Prod Example: https://4q7ajbemgk.execute-api.us-east-2.amazonaws.com/Prod/pokemon/pikachu

Pokemon Data API

/pokemon/{id}/{level}

• id : number or name

/moves/{id}

• id: number

/damage_multiplier/{type1}/{type2}

• type1: name of type
• type2: name of type

Requirements

• AWS CLI already configured with PowerUser permission
• AWS SAM CLI installed
• .NET Core 2.1 installed. Please review the Currently Supported Patch for your project type.
• Docker installed

Recommended Tools for Visual Studio / Visual Studio Code Users

• AWS Toolkit for Visual Studio
• AWS Extensions for .NET CLI which are AWS extensions to the .NET CLI focused on building .NET Core and ASP.NET Core applications and deploying them to AWS services including Amazon Elastic Container Service, AWS Elastic Beanstalk and AWS Lambda.

Note: this project uses Cake Build for build, test and packaging requirements. You do not need to have the AWS Extensions for .NET CLI installed, but are free to do so if you which to use them. Version 3 of the Amazon.Lambda.Tools does require .NET Core 2.1 for installation, but can be used to deploy older versions of .NET Core.

• Cake Build Editor support for Visual Studio Code and Visual Studio.

Other resources

• Please see the Learning Reasources section on the AWS Lambda for .NET Core GitHub repository.
• The official AWS X-Ray SDK for .NET

Build, Packaging, and Deployment

This solution comes with a pre-configured Cake (C# Make) Build script which provides a cross-platform build automation system with a C# DSL for tasks such as compiling code, copying files and folders, running unit tests, compressing files and building NuGet packages.

The build.cake script has been set up to:

• Build your solution projects
• Run your test projects
• Package your functions
• Run your API in SAM Local.

To execute a build use the following commands:

Linux & macOS

sh build.sh --target=Package

Windows (Powershell)

build.ps1 --target=Package

To package additional projects / functions add them to the build.cake script "project section".

var projects = new []
{
    sourceDir.Path + "Pokemon_API/Pokemon_API.csproj",
    sourceDir.Path + "{PROJECT_DIR}/{PROJECT_NAME}.csproj"
};

AWS Lambda C# runtime requires a flat folder with all dependencies including the application. SAM will use CodeUri property to know where to look up for both application and dependencies:

...
    GetPokemon:
        Type: AWS::Serverless::Function
        Properties:
            CodeUri: ./artifacts/Pokemon_API.zip
            ...

Deployment

First and foremost, we need an S3 bucket where we can upload our Lambda functions packaged as ZIP before we deploy anything - If you don't have a S3 bucket to store code artifacts then this is a good time to create one:

aws s3 mb s3://BUCKET_NAME

Next, run the following command to package our Lambda function to S3:

sam package --template-file template.yaml --output-template-file packaged.yaml --s3-bucket deploys.my-sid

Next, the following command will create a Cloudformation Stack and deploy your SAM resources.

sam deploy --template-file packaged.yaml --stack-name PokemonApi --capabilities CAPABILITY_IAM

See Serverless Application Model (SAM) HOWTO Guide for more details in how to get started.

After deployment is complete you can run the following command to retrieve the API Gateway Endpoint URL:

aws cloudformation describe-stacks \
    --stack-name pokemon_api \
    --query 'Stacks[].Outputs'

Testing

For testing our code, we use XUnit and you can use dotnet test to run tests defined under test/

dotnet test Pokemon_API.Test

Alternatively, you can use Cake. It discovers and executes all the tests.

Linux & macOS

sh build.sh --target=Test

Windows (Powershell)

build.ps1 --target=Test

Local development

Given that you followed Packaging instructions then run the following to invoke your function locally:

Invoking function locally through local API Gateway

sam local start-api

SAM Local is used to emulate both Lambda and API Gateway locally and uses our template.yaml to understand how to bootstrap this environment (runtime, where the source code is, etc.) - The following excerpt is what the CLI will read in order to initialize an API and its routes:

...
Events:
    sam-app:
        Type: Api # More info about API Event Source: https://github.com/awslabs/serverless-application-model/blob/master/versions/2016-10-31.md#api
        Properties:
            Path: /hello
            Method: get

If the previous command run successfully you should now be able to hit the following local endpoint to invoke your function http://localhost:3000/REPLACE-ME-WITH-ANYTHING.

Appendix

AWS CLI commands

AWS CLI commands to package, deploy and describe outputs defined within the cloudformation stack:

aws cloudformation package \
    --template-file template.yaml \
    --output-template-file packaged.yaml \
    --s3-bucket REPLACE_THIS_WITH_YOUR_S3_BUCKET_NAME

aws cloudformation deploy \
    --template-file packaged.yaml \
    --stack-name pokemon_api \
    --capabilities CAPABILITY_IAM \
    --parameter-overrides MyParameterSample=MySampleValue

aws cloudformation describe-stacks \
    --stack-name timeinterpreter --query 'Stacks[].Outputs'

Bringing to the next level

Here are a few ideas that you can use to get more acquainted as to how this overall process works:

• Create an additional API resource (e.g. /hello/{proxy+}) and return the name requested through this new path
• Update unit test to capture that
• Package & Deploy

Next, you can use the following resources to know more about beyond hello world samples and how others structure their Serverless applications:

• AWS Serverless Application Repository