pgermishuys / hoverfly-dotnet

A .Net Library for Hoverfly

hoverfly-dotnet

A .Net Library for Hoverfly (http://hoverfly.io/)

Hoverfly is maintained by SpectoLabs (https://specto.io/)

What is Hoverfly DotNet?

Hoverfly is a lightweight service virtualisation tool which allows you to stub / simulate HTTP(S) services. It is a proxy written in Go which responds to HTTP(S) requests with stored responses, pretending to be it’s real counterpart.

It enables you to get around common testing problems caused by external dependencies, such as non-deterministic data, flakiness, not yet implemented API’s, licensing fees, slow tests and more.

Hoverfly .Net is a native language binding which gives you an expressive API for managing Hoverfly in .Net. It gives you a Hoverfly class which abstracts away the binary and API calls.

###Example of using simulation:

var hoverfly = new Hoverfly(HoverflyMode.Simulate);

hoverfly.Start();

var result = //Use HttpClient to get content, e.g. "http://time.jsontest.com";

// This call will not reach the destination URL, insted Hoverfly will return a first call that is recorded.
var result2 = //Use HttpClient to get content, e.g. "http://time.jsontest.com";

hoverfly.Stop();

###Capture and export simulations:

var hoverfly = new Hoverfly(HoverflyMode.Capture);

hoverfly.Start();

// use for example HttpClient to make a call to a URL, e.g. "http://echo.jsontest.com/key/value/one/two");

hoverfly.ExportSimulation("simulation.json");

hoverfly.Stop();

###Import recorded simulations into hoverfly:

var hoverfly = new Hoverfly(HoverflyMode.Simulate);

hoverfly.Start();

hoverfly.ImportSimulation(new FileSimulationSource("simulation.json"));

// use for example HttpClient to make a call to a URL, e.g. "http://echo.jsontest.com/key/value/one/two");
// and it will return the result from the imported recorded simulation

hoverfly.Stop();

###Specify your own simulations for a call to specific URL with Hoverfly.Dsl:

using static Hoverfly.Dsl.HoverflyDsl;
using static Hoverfly.Dsl.ResponseCreators;
using static Hoverfly.Dsl.DslSimulationSource;
    
...

var hoverfly = new Hoverfly(HoverflyMode.Simulate);

hoverfly.Start();

hoverfly.ImportSimulation(DslSimulationSource.Dsl(
                Service("http://echo.jsontest.com")
                    .Get("/key/value/three/four")
                    .WillReturn(Success("Hello World!", "plain/text"))));

// Every call (using for example HttpClient) to the URL http://echo.jsontest.com/key/value/three/four
// will now return the specified success response in the imported simulation. This will happen as 
// long as hoverfly is running.
var result = <Http Get Content From "http://echo.jsontest.com/key/value/three/four">

hoverfly.Stop();

###Example of using hoverfly in a integration test:

Hoverfly hoverfly;

void StartUp()
{
    hoverfly = new Hoverfly(HoverflyMode.Simulate);
    hoverfly.ImportSimulation("simulation.json");
    hoverfly.Start();
}

void MyTest()
{
    var myController = new MyController();
    
    var result = myController.Get("10");
    
    Assert.Eqaul(result.StatusCode, 200);
}

void TearDown()
{
   hoverfly.Stop();
}

MyController, using ASP.Net Core

[Route("api/[controller]")]
public class MyController : Controller
{
   [HttpGet]
   public IActionResult Get(string userId)
   {
       // Assume this code integrates with another service (maybe a Microservice :P) over HTTP with HttpClient
       // httpClient.GetAsync("http://mysuper.microservice.com/foo");
       
       ...
       
       return result;
   }
}

Hoverfly will add a Proxy and all Http calls will go through that proxy. Hoverfly will in simulation mode return a recorded result for a given Http call, so no extrenal call will be made. With the use of hoverfly in our integration/component test we don't need to create fakes to avoid extrenal calls. With hoverfly we can also in our tests simulate delays on certain extrenal calls etc. For example to test timeouts etc.