AWS Lambda in C#

2. What to Expect from the Session • Brief Introduction to AWS Lambda • Why .NET Core • New .NET Core Lambda tooling • Lots of exciting demos!

3. AWS Lambda Crash Course • Compute part of the AWS serverless architecture • Zero administration • Event-driven scaling • Never pay for idle time • Upload your code and go

4. Why .NET Core? • Performance • Modularized design • Low memory usage • Open Source • Built and validated for Amazon Linux • Allow AWS to respond to security issues • Cross Platform • Develop on any platform and run on Amazon Linux

5. .NET Core Development • .NET Core 1.0 • https://www.microsoft.com/net/download/core • Visual Studio 2015 Update 3 • Visual Studio 2015 Tools (Preview 2) • Target framework netcoreapp1.0 • Package with .NET Core CLI “dotnet publish” • Upload as a zip file

6. Declaring Lambda Functions • Static or instance methods • Must have a default constructor for instance methods • Can take 0 or 1 input parameters public void FunctionHandler() public void FunctionHandler(S3Event evnt) public string FunctionHandler(S3Event evnt, ILambdaContext context) • Optional ILambdaContext parameter

7. • async methods must return a Task or Task<T> Declaring Lambda Functions public async Task FunctionHandler<T>(T obj, ILambdaContext context) public void FunctionHandler<T>(T obj, ILambdaContext context) • No generic methods public async Task FunctionHandler(S3Event evnt, ILambdaContext context) // return void public async Task<MyType> FunctionHandler(S3Event evnt, ILambdaContext context)

8. Invoking Lambda Functions

9. Invoking from AWS Lambda Event Sources • Function executes in response to events in AWS services • A few of the supported services • Amazon S3 • Amazon DynamoDB • Amazon Kinesis • …. • Scheduled Events

10. Invoking with the AWS SDKs • Invoke methods using any SDK • Great for mobile apps • Manage credentials with Amazon Cognito var client = new AmazonLambdaClient(cognitoCredentials, RegionEndpoint.USWest2); var request = new InvokeRequest { FunctionName = "ProcessGameScore", Payload = gameStats }; InvokeResponse response = await client.InvokeAsync(request);

11. Invoking from Amazon API Gateway • Frontend of the AWS Serverless architecture • Expose Lambda functions as HTTP API • Manages authentication, versioning, monitoring and more

12. Demo Time

13. Demo: Responding to AWS Events

14. Recap • Created a new Lambda project in Visual Studio • Learned how serialization works • Learned about the handler format • assemblyname::namespaced-classname::methodname • Published from Visual Studio • Configured AWS event source • Invoked the Lambda function from Visual Studio

15. Demo: Cross Platform: Command Line

16. Yeoman Project Generators • Project generator ecosystem • Installable via npm: • Node.js dependency • npm install –g yo • AWS Lambda generators • npm install –g generator-aws-lambda-dotnet • yo aws-lambda-dotnet

17. Recap Cross-Platform Demo • Created a project with Yeoman • npm install –g yo generator-aws-lambda-dotnet • yo aws-lambda-dotnet • Develop with any editor • Command line deployment with the .NET CLI and Amazon.Lambda.Tools NuGet package • dotnet lambda <command> <args> • In preview

18. Demo: Serverless Application

19. Demo Application Architecture internet GetBlogs() GetBlog() AddBlog() RemoveBlog() API Gateway AWS Lambda Amazon DynamoDB AWS CloudFormation Stack

20. Our Serverless Application Deployment Visual Studio Project Amazon S3 AWS CloudFormation App bundle (.zip) Serverless template 2: Request stack …other resources Lambda Functions …other resources API Gateway 4: Stack launched 3: Fetch template

21. Recap Serverless Application • Created an AWS Serverless application • Learned about the serverless.template file • Exposed Lambda functions as a HTTP API • Deployed using AWS CloudFormation

22. ASP.NET Core and Web API • ASP.NET Core is the web framework for .NET Core • Includes framework for building Web API applications • Define API controllers to respond to requests • Maps request data to function parameters [Route("api/[controller]")] public class ValuesController : Controller { // PUT api/values/5 [HttpPut("{id}")] public void Put(int id, [FromBody]string value) { ... } ...

23. How can we use ASP.NET Core in Lambda? • Amazon API Gateway Proxy Integration • Forwards all requests to a Lambda Function • Lambda Function • Converts how requests and responses are represented between API Gateway and ASP.NET Core • Implemented by Amazon.Lambda.AspNetCoreServer NuGet package • Currently in preview

24. ASP.NET Core Web API Architecture IIS / Nginx Kestrel ASP.NET Core Hosting User’s Web API Controllers Internet

25. ASP.NET Core Architecture on Lambda API Gateway Lambda ASP.NET Core Hosting User’s Web API Controllers Internet

26. Demo: ASP.NET Core Web API

27. Recap ASP.NET Core Web API Demo • Used existing ASP.NET Core framework • No change to controller code • Used API Gateway Proxy Integration to forward all requests • Lambda function translates between API Gateway and ASP.NET Core • Amazon.Lambda.AspNetCoreServer NuGet Package • In preview • Looked at the handler source in GitHub

28. Useful Links • AWS Toolkit for Visual Studio • https://aws.amazon.com/visualstudio/ • AWS Lambda .NET GitHub • https://github.com/aws/aws-lambda-dotnet • AWS .NET Developer Blog • https://aws.amazon.com/blogs/developer/category/net/ • AWS Lambda Developer Guide • http://docs.aws.amazon.com/lambda/latest/dg/welcome.html • AWS Toolkit for Visual Studio Guide • http://docs.aws.amazon.com/toolkit-for-visualstudio/latest/user-guide/welcome.html

29. Other Related Sessions CMP211 - Getting Started with Serverless Architectures SRV202 – What’s New with AWS Lambda DEV301 - Amazon CloudWatch Logs and AWS Lambda: A Match Made in Heaven MBL306 - Serverless Authentication and Authorization: Identity Management for Serverless Architectures SVR311 - The State of Serverless Computing

30. Thank you!

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AWS Lambda in C#

Amazon Web Services

AWS Lambda in C#