As you know Micro service is one alternative approach to write Web API method. There are so many ways to create the micro-service. But in this post i m going to write creating micro service using Amazon Web Service(AWS) Lambda ToolKit on Asp.net Core
what is the Serverless Microservices ?
Serverless microservices are deployed within a serverless vendor’s infrastructure and only run when they are needed by the application. Depending on the size of a microservice, it may also be broken up into even smaller functions.
It doesn’t means that there will be no server. There will be cloud vendor’s server.
AWS use the Lamda and API gateways for this functionalities.


What are the advantages of this approach ?
1. You don’t have to pay for idle server time. So it will save huge deployment cost
2. If you have small application like POC and you are going to use that application for specific time interval then this approach will good. It will save huge money.
3. On demand we can scale the application, since it is on cloud.
4. It is give good performance as compare to monolithic approach.
How to create Serverless microservice with AWS
Step 1: Install the AWS Toolkit Extension as given below

Step 2: Create the Web Api Serverless Project like this

This template will add the all the requited dll and required files for us to making serverless microservice

Step 3: Add some Empty API controller in Controller folder and write some test method like this
using Microsoft.AspNetCore.Mvc;
using System;
using System.Collections.Generic;
using System.Net.Http;
namespace AWSServerless3.Controllers
{
[Route("api/[controller]")]
[ApiController]
public class TestController : ControllerBase
{
// GET: api/Test
[HttpGet]
public IEnumerable<string> Get()
{
return new string[] { "value1", "This is from Test Controller" };
}
//external
[HttpGet]
[Route("external")]
public string External()
{
try
{
HttpClient client = new HttpClient();
var requestTask = client.GetStringAsync("http://www.chandradev819.wordpress.com");
requestTask.Wait();
return "external connectivity PASS";
}
catch (Exception e)
{
return "external connectivity FAIL";
}
}
}
}
Add one more controller i.e EmpController
using Microsoft.AspNetCore.Mvc;
using System.Collections.Generic;
namespace AWSServerless3.Controllers
{
[Route("api/[controller]")]
[ApiController]
public class EmpController : ControllerBase
{
// GET: api/Emp
[HttpGet]
public IEnumerable<string> Get()
{
return new string[] { "value1", "This is from Emp Controller" };
}
}
}
Step 4; Build the application and run on local machine before deployment

Now We are good to deploy on AWS. Now we have to create the profile on
https://aws.amazon.com/
Configure AWS user credentials as given below post
https://docs.aws.amazon.com/toolkit-for-visual-studio/latest/user-guide/credentials.html
Step 5: After successfully configure, Right click on Solution explores and deploy the application like this

Now publish the application on AWS Cloud like this


After published we will get the URL like this

Now our services has been deployed as Server less microservice on AWS Cloud. We donot have to do any thing.
Now we are ready to use the microservice on our application



Summary
I hope in this small post you might have got clear idea about creating Serverless Microservice using AWS Lambda Toolkit in Asp.net Core application.