Blazor Testing which involves protected session storage

Question

System.InvalidOperationException HResult=0x80131509 Message=Unable to resolve service for type 'Microsoft.AspNetCore.DataProtection.IDataProtectionProvider' while attempting to activate 'Microsoft.AspNetCore.Components.Server.ProtectedBrowserStorage.ProtectedSessionStorage'. Source=Microsoft.Extensions.DependencyInjection StackTrace: at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteFactory.CreateArgumentCallSites(Type implementationType, CallSiteChain callSiteChain, ParameterInfo[] parameters, Boolean throwIfCallSiteNotFound) at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteFactory.CreateConstructorCallSite(ResultCache lifetime, Type serviceType, Type implementationType, CallSiteChain callSiteChain) at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteFactory.TryCreateExact(ServiceDescriptor descriptor, Type serviceType, CallSiteChain callSiteChain, Int32 slot) at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteFactory.CreateCallSite(Type serviceType, CallSiteChain callSiteChain) at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteFactory.GetCallSite(Type serviceType, CallSiteChain callSiteChain) at Microsoft.Extensions.DependencyInjection.ServiceProvider.CreateServiceAccessor(Type serviceType) at System.Collections.Concurrent.ConcurrentDictionary2.GetOrAdd(TKey key, Func2 valueFactory) at Microsoft.Extensions.DependencyInjection.ServiceProvider.GetService(Type serviceType, ServiceProviderEngineScope serviceProviderEngineScope) at Microsoft.Extensions.DependencyInjection.ServiceLookup.ServiceProviderEngineScope.GetService(Type serviceType) at Bunit.TestServiceProvider.GetServiceInternal(Type serviceType) at Bunit.TestServiceProvider.GetService(Type serviceType) at Microsoft.AspNetCore.Components.ComponentFactory.<>c__DisplayClass7_0.g__Initialize|1(IServiceProvider serviceProvider, IComponent component) at Microsoft.AspNetCore.Components.ComponentFactory.PerformPropertyInjection(IServiceProvider serviceProvider, IComponent instance) at Microsoft.AspNetCore.Components.ComponentFactory.InstantiateComponent(IServiceProvider serviceProvider, Type componentType) at Microsoft.AspNetCore.Components.RenderTree.Renderer.InstantiateChildComponentOnFrame(RenderTreeFrame& frame, Int32 parentComponentId) at Microsoft.AspNetCore.Components.RenderTree.RenderTreeDiffBuilder.InitializeNewComponentFrame(DiffContext& diffContext, Int32 frameIndex) at Microsoft.AspNetCore.Components.RenderTree.RenderTreeDiffBuilder.InitializeNewSubtree(DiffContext& diffContext, Int32 frameIndex) at Microsoft.AspNetCore.Components.RenderTree.RenderTreeDiffBuilder.InsertNewFrame(DiffContext& diffContext, Int32 newFrameIndex) at Microsoft.AspNetCore.Components.RenderTree.RenderTreeDiffBuilder.AppendDiffEntriesForRange(DiffContext& diffContext, Int32 oldStartIndex, Int32 oldEndIndexExcl, Int32 newStartIndex, Int32 newEndIndexExcl) at Microsoft.AspNetCore.Components.RenderTree.RenderTreeDiffBuilder.ComputeDiff(Renderer renderer, RenderBatchBuilder batchBuilder, Int32 componentId, ArrayRange1 oldTree, ArrayRange1 newTree) at Microsoft.AspNetCore.Components.Rendering.ComponentState.RenderIntoBatch(RenderBatchBuilder batchBuilder, RenderFragment renderFragment, Exception& renderFragmentException) at Microsoft.AspNetCore.Components.RenderTree.Renderer.ProcessRenderQueue() --- End of stack trace from previous location --- at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw() at Bunit.Rendering.TestRenderer.AssertNoUnhandledExceptions() at Bunit.Rendering.TestRenderer.Render[TResult](RenderFragment renderFragment, Func`2 activator) at Bunit.Rendering.TestRenderer.RenderFragment(RenderFragment renderFragment) at Bunit.Extensions.TestContextBaseRenderExtensions.RenderInsideRenderTree(TestContextBase testContext, RenderFragment renderFragment) at Bunit.Extensions.TestContextBaseRenderExtensions.RenderInsideRenderTree[TComponent](TestContextBase testContext, RenderFragment renderFragment) at Bunit.TestContext.Render[TComponent](RenderFragment renderFragment) at Bunit.TestContext.RenderComponent[TComponent](ComponentParameter[] parameters) at ConfigWebappUnitTesting.AssetTableTest..ctor() in D:\Gleason Projects\ConfigurationWebAppBlazor\ConfigWebappUnitTesting\AssetTableTest.cs:line 19 at System.RuntimeType.CreateInstanceDefaultCtor(Boolean publicOnly, Boolean wrapExceptions)

This exception was originally thrown at this call stack: [External Code] ConfigWebappUnitTesting.AssetTableTest.AssetTableTest() in AssetTableTest.cs

AssetTable.cs with constructor

public AssetTableTest()
        {
            // Act
            var session = Context.Services.GetService<FakeSignOutSessionStateManager>();
            var page = Context.Services.GetService<FakeNavigationManager>();
            page.NavigateTo(page.BaseUri.Remove(page.BaseUri.Length - 1, 1) + Configuration["Session"]);
            cut = Context.RenderComponent<Assets>(); //**Got My error at this point**
            //cut = Context.RenderComponent<Assets>(x =>
            //x.Add(p => p.Session, Configuration["Session"])
            //);

            //WaitForAssertion
            cut.WaitForAssertion(() => { }, TimeSpan.FromSeconds(5));
            cut.WaitForState(() => (cut.Markup.Contains("tbody")), TimeSpan.FromSeconds(10));
            cut.WaitForState(() => (!cut.Find("tbody").TextContent.Contains("Loading")), TimeSpan.FromSeconds(50));
            tableBody = cut.Find("tbody");
        }

Answer 1

That exception is saying that you are missing a valid implementation for the IDataProtectionProvider service interface. In ASP.NET apps, this is typically done in Program.cs or Startup.cs (depending on the project and version of .NET). The Microsoft.AspNetCore.DataProtection package provides an extension method for ServiceCollection to accomplish this.

For you, it might look something like:

// Assuming Context.Services is a ServiceCollection:
Context.Services.AddDataProtection();