# ASP.NET Core Web API Serverless Application

This project shows how to run an ASP.NET Core Web Application as a serverless application. The NuGet package [Amazon.Lambda.AspNetCoreServer](https://www.nuget.org/packages/Amazon.Lambda.AspNetCoreServer) contains a Lambda function that is used to translate requests from API Gateway into the ASP.NET Core framework and then the responses from ASP.NET Core back to API Gateway.

### Adding AWS SDK for .NET ###

To integrate the AWS SDK for .NET with the dependency injection system built into ASP.NET Core add the NuGet 
package [AWSSDK.Extensions.NETCore.Setup](https://www.nuget.org/packages/AWSSDK.Extensions.NETCore.Setup/). Then in 
the `ConfigureServices` method  in `Startup.cs` file register the AWS service with the `IServiceCollection`.

```csharp
public void ConfigureServices(IServiceCollection services)
{
    services.AddMvc();

    // Add S3 to the ASP.NET Core dependency injection framework.
    services.AddAWSService<Amazon.S3.IAmazonS3>();
}
```

### Configuring for Application Load Balancer ###

To configure this project to handle requests from an Application Load Balancer instead of API Gateway change
the base class of `LambdaEntryPoint` from `Amazon.Lambda.AspNetCoreServer.APIGatewayProxyFunction` to 
`Amazon.Lambda.AspNetCoreServer.ApplicationLoadBalancerFunction`.

### Project Files ###

* serverless.template - an AWS CloudFormation Serverless Application Model template file for declaring your Serverless functions and other AWS resources
* aws-lambda-tools-defaults.json - default argument settings for use with Visual Studio and command line deployment tools for AWS
* LambdaEntryPoint.cs - class that derives from **Amazon.Lambda.AspNetCoreServer.APIGatewayProxyFunction**. The code in 
this file bootstraps the ASP.NET Core hosting framework. The Lambda function is defined in the base class.
Change the base class to **Amazon.Lambda.AspNetCoreServer.ApplicationLoadBalancerFunction** when using an 
Application Load Balancer.
* LocalEntryPoint.cs - for local development this contains the executable Main function which bootstraps the ASP.NET Core hosting framework with Kestrel, as for typical ASP.NET Core applications.
* Startup.cs - usual ASP.NET Core Startup class used to configure the services ASP.NET Core will use.


## Here are some steps to follow from Visual Studio:

To deploy your Serverless application, right click the project in Solution Explorer and select *Publish to AWS Lambda*.

To view your deployed application open the Stack View window by double-clicking the stack name shown beneath the AWS CloudFormation node in the AWS Explorer tree. The Stack View also displays the root URL to your published application.

## Here are some steps to follow to get started from the command line:

Once you have edited your template and code you can deploy your application using the [Amazon.Lambda.Tools Global Tool](https://github.com/aws/aws-extensions-for-dotnet-cli#aws-lambda-amazonlambdatools) from the command line.

Install Amazon.Lambda.Tools Global Tools if not already installed.
```
    dotnet tool install -g Amazon.Lambda.Tools
```

If already installed check if new version is available.
```
    dotnet tool update -g Amazon.Lambda.Tools
```

Execute unit tests
```
    cd "BlueprintBaseName.1/test/BlueprintBaseName.1.Tests"
    dotnet test
```

Deploy application
```
    cd "BlueprintBaseName.1/src/BlueprintBaseName.1"
    dotnet lambda deploy-serverless
```