Mocking HTTP client errors

[ProjectFoxx]

Hey everyone,

Hope someone can help me

I was trying to mock the HTTP client and i followed the docs
https://bunit.dev/docs/test-doubles/mocking-httpclient.html

But when i have the line in the AddMockHttpClient function
services.AddSingleton(httpClient); i get an error so i commented that one

I removed that code and also tried the code from the docs from
https://github.com/richardszalay/mockhttp

Both times i get the error with no baseaddress set

My test has the following code :

using var ctx = new TestContext();
var mock = ctx.Services.AddMockHttpClient();
mock.When("/getData").RespondJson(new List<Data>{ ... });

ctx.RenderComponent<ComponentWithAuth>();

But when i mocked the HTTP client i still have the error on the render component line that i dont have a Baseaddress set

[linkdotnet]

Hey @ProjectFoxx,

can you post one complete and minimal example? Especially the error of services.AddSingleton(httpClient); would be interesting to know.

[ProjectFoxx]

Hey @linkdotnet

Thx for responding
The error i get on the services.AddSingleton(httpClient); is:

System.InvalidOperationException : New services/implementations cannot be registered with the Services provider in a TestContext, after the first services has been retrieved from it using e.g. the GetService or GetRequiredService methods. This typically happens when a component is rendered, so make sure all services are added before that.

Stacktrace:
Stack Trace:  TestServiceProvider.CheckInitializedAndThrow() line 173 TestServiceProvider.Add(ServiceDescriptor item) line 145 ServiceCollectionServiceExtensions.AddSingleton(IServiceCollection services, Type serviceType, Object implementationInstance) ServiceCollectionServiceExtensions.AddSingleton[TService](IServiceCollection services, TService implementationInstance) MockedHttpClient.AddMockHttpClient(TestServiceProvider services) line 21

Also tried this one from the richard github

var mockHttp = new MockHttpMessageHandler();

        var jsonMock = JsonConvert.SerializeObject(MockData);

        Console.WriteLine(jsonMock);
        // Setup a respond for the user api (including a wildcard in the URL)
        mockHttp.When("http://localhost/api/getdata")
                .Respond("application/json", jsonMock); // Respond with JSON

        // Inject the handler or client into your application code
        var client = mockHttp.ToHttpClient();

        var response = await client.GetAsync("http://localhost/api/getdata");

        var json = await response.Content.ReadAsStringAsync();

        // No network connection required
        Console.Write(json); 

This test runs but it is without the component
i tried this code above the component both times i get the baseurl error

Hope you can help me

[ProjectFoxx]

Loadservices(){

            testContext.Services.AddSingleton<ApiService>(new ApiService(new System.Net.Http.HttpClient()));
            testContext.Services.AddSingleton<NavigationManager, MockNavigationManager>();
            testContext.Services.AddSingleton<LicenseService, MockedLicenseService>();

            navigationManager = testContext.Services.GetService<NavigationManager>();
            licenseService = testContext.Services.GetService<LicenseService>();

            testContext.Services.GetRequiredService<HttpClient>(); // i tried this but doesnt work
}

Test:

LoadServices()
navigationManager.NavigateTo("articles");

var mock = ctx.Services.AddMockHttpClient();
mock.When("/getData").RespondJson(new List<Data>{ ... });

var page = ctx.RenderComponent<ComponentWithAuth>();

page.Find("button").MarkupMatches("Delete");

Before this i load all services in the setup:

` testContext = new Bunit.TestContext();

        testContext.Services.TryAddScoped<BrowserService>();
        testContext.Services.AddBlazoredLocalStorage();

        testContext.Services.TryAddScoped<LocalizationService>();
        testContext.Services.TryAddScoped<ApiService>();

        testContext.Services.TryAddScoped<NavigationService>();
        testContext.Services.TryAddScoped<SignOutSessionStateManager>();
        testContext.Services.TryAddScoped<AuthenticationService>();

        testContext.Services.AddAuthorizationCore();
        testContext.Services.AddApiAuthorization().AddAccountClaimsPrincipalFactory<CustomUserFactory>();
        testContext.Services.TryAddScoped<Authorization>();

        testContext.AddTestAuthorization()

.SetAuthorized("sffsdf.fsffe.com")
.SetRoles("Administrator");

        testContext.Services.AddSingleton<IModalService, ModalService>();

        //Syncfusion Blazor service and Ignore script isolation.
        testContext.Services.AddSyncfusionBlazor(options =>
        {
            options.IgnoreScriptIsolation = true;
        });
        testContext.Services.AddOptions();`

 [TearDown]
        public void TearDown()
        {
            testContext.Dispose();
        }

[egil]

You are calling GetService in Loadservices before you call AddMockHttpClient, That is not supported, as the exception message says.

[ProjectFoxx]

even when i remove this line i still get the error
testContext.Services.GetRequiredService<HttpClient>();

[linkdotnet]

You called GetService 3 times in LoadServices. Basically you have to de-couple your logic in two parts: One part which is solely responsible for registering services / building up your DI container. Afterwards you can consume services. Basically you are not allowed to register additional services after you got the first instance from the service container.

Alternatively put the AddMockHttpClient into LoadServices before you retrieve any instance via GetService or GetRequiredService.

[ProjectFoxx]

@linkdotnet @egil thx for your help :)
i changed the location of the AddMockHttpClient above the get services of loadservices and now it works :)

You helped me with this problem i have been stuck a few days already