Durable Azure Functions and Integration Tests - azure

Question

I'm trying to test (integration tests) my Azure Durable Function v3 with SpecFlow and MSTest.
Functions are initialized with DI and Startup class:
[assembly: FunctionsStartup(typeof(Startup))]
namespace MyNamespace.Functions
{
public class Startup : FunctionsStartup
{
public override void Configure(IFunctionsHostBuilder builder)
{
ConfigureServices(builder.Services);
}
...
Orchestrator entry point is triggered by HTTP endpoint:
public class Function1
{
[FunctionName(nameof(Function1))]
public async Task<IActionResult> DoYourJob(
[HttpTrigger(AuthorizationLevel.Anonymous, methods: "post", Route = "api/routes/function1")] HttpRequestMessage httpRequest,
[DurableClient] IDurableOrchestrationClient starter)
{
...
My IntegrationTest constructor initializes Az Function with HostBuilder (thanks to this article):
[Binding]
public sealed class Function1StepDefinitions
{
private readonly IHost _host;
private readonly Function1 _function;
public Function1StepDefinitions()
{
var startup = new MyNamespace.Functions.Startup();
_host = new HostBuilder()
.ConfigureWebJobs(config =>
{
config.AddDurableTask(options =>
{
options.HubName = "MyTaskHub";
});
startup.Configure(config);
})
.ConfigureServices(ReplaceTestOverrides) // Method to replace/mock some external services
.Build();
_function = new Function1(Host.Services.GetRequiredService<IOptions..., ..);
And in my test I dont know how to retrieve IDurableOrchestrationClient to call my HTTP Trigger:
[When(#"I call my function")]
public async Task WhenICallMyFunction()
{
var request = new HttpRequestMessage();
await _function.DoYourJob(
request,
Host.Services.GetService<IDurableOrchestrationClient>()); // This is always null
...
Is there a way to retrieve this IDurableOrchestrationClient and test my whole Function (with Orchestrator and Activities calls)?

Answer 1

Looks like there is a IDurableClientFactory that you can inject instead based on this code.
Using this, you can create a client to use as shown in this sample.