HttpNavigationManager already initialized on Blazor SSR.

[benjaminsampica]

Is there an existing issue for this?

• I have searched the existing issues

Describe the bug

I'm trying to use the UseExceptionHandler middleware to handle exceptions thrown when Blazor server-side rendering pages and am receiving an unexpected error when the middleware executes.

Expected Behavior

The request re-executes and I'm sent to my error page.

Steps To Reproduce

1. Create a new blazor web project - dotnet new blazor
2. Create an /Error page (the template is missing this page despite having the exception handler go there).
3. Run the project with anything other than the Development environment.

These steps in a repo -> https://github.com/benjaminsampica/BlazorServerSideRendering

Exceptions (if any)

System.InvalidOperationException: 'HttpNavigationManager' already initialized.
   at Microsoft.AspNetCore.Components.NavigationManager.Initialize(String baseUri, String uri)
   at Microsoft.AspNetCore.Components.Endpoints.EndpointHtmlRenderer.InitializeStandardComponentServicesAsync(HttpContext httpContext, Type componentType, String handler, IFormCollection form)
   at Microsoft.AspNetCore.Components.Endpoints.RazorComponentEndpointInvoker.RenderComponentCore()
   at Microsoft.AspNetCore.Components.Rendering.RendererSynchronizationContext.<>c.<<InvokeAsync>b__9_0>d.MoveNext()
--- End of stack trace from previous location ---
   at Microsoft.AspNetCore.Diagnostics.ExceptionHandlerMiddlewareImpl.HandleException(HttpContext context, ExceptionDispatchInfo edi)
Microsoft.AspNetCore.Server.Kestrel: Error: Connection id "0HMS6ET6U8UL7", Request id "0HMS6ET6U8UL7:00000001": An unhandled exception was thrown by the application.

.NET Version

.NET 8 preview 6

Anything else?

No response

[mkArtakMSFT]

Related scenario: #49853

[SteveSandersonMS]

Thanks for reporting this, @benjaminsampica

I tried to reproduce this with the current RC1 build and was not able to do so. Specifically,

1. Worked inside a Blazor Web project
2. Modified the Counter.razor page to throw an unhandled exception during OnInitialized
3. Ran the app with --environment production
4. Clicked on the counter link

The result I got was the exception message that I had added myself in step 2, which is the desired behavior. I didn't get "'HttpNavigationManager' already initialized.".

Are you able to try your exact repro case again with the RC1 release, and if you can still recreate the problem, give us more details on how to do so? Thanks!

[ghost]

Hi @benjaminsampica. We have added the "Needs: Author Feedback" label to this issue, which indicates that we have an open question for you before we can take further action. This issue will be closed automatically in 7 days if we do not hear back from you by then - please feel free to re-open it if you come back to this issue after that time.

[benjaminsampica]

@SteveSandersonMS I'm still seeing this with the 8.0.0-rc2 build from here . I updated the above repo link with a nuget.config that allows for rc2 and showcases the problem. For clarity, the actual exception is thrown, but an exception is thrown while attempting to redirect as well and I get a 500 instead of being redirected to the error page.

Here's the entire stacktrace.

Exception thrown: 'System.Exception' in BlazorServerSideRendering.dll
An exception of type 'System.Exception' occurred in BlazorServerSideRendering.dll but was not handled in user code

'BlazorServerSideRendering.exe' (CoreCLR: clrhost): Loaded 'C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App\8.0.0-rc.2.23421.27\Microsoft.AspNetCore.Diagnostics.Abstractions.dll'. Skipped loading symbols. Module is optimized and the debugger option 'Just My Code' is enabled.
Microsoft.AspNetCore.Diagnostics.ExceptionHandlerMiddleware: Error: An unhandled exception has occurred while executing the request.

System.Exception: Exception of type 'System.Exception' was thrown.
   at BlazorServerSideRendering.Pages.Index.OnInitialized() in C:\Users\Ben\source\repos\BlazorServerSideRendering\Pages\Index.razor:line 13
   at Microsoft.AspNetCore.Components.ComponentBase.RunInitAndSetParametersAsync()
   at Microsoft.AspNetCore.Components.Rendering.ComponentState.SetDirectParameters(ParameterView parameters)
   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, ArrayRange`1 oldTree, ArrayRange`1 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 Microsoft.AspNetCore.Components.RenderTree.Renderer.ProcessRenderQueue()
   at Microsoft.AspNetCore.Components.RenderTree.Renderer.AddToRenderQueue(Int32 componentId, RenderFragment renderFragment)
   at Microsoft.AspNetCore.Components.ComponentBase.StateHasChanged()
   at Microsoft.AspNetCore.Components.ComponentBase.CallOnParametersSetAsync()
   at Microsoft.AspNetCore.Components.ComponentBase.RunInitAndSetParametersAsync()
   at Microsoft.AspNetCore.Components.Rendering.ComponentState.SetDirectParameters(ParameterView parameters)
   at Microsoft.AspNetCore.Components.RenderTree.Renderer.RenderRootComponentAsync(Int32 componentId, ParameterView initialParameters)
   at Microsoft.AspNetCore.Components.HtmlRendering.Infrastructure.StaticHtmlRenderer.BeginRenderingComponent(IComponent component, ParameterView initialParameters)
   at Microsoft.AspNetCore.Components.Endpoints.EndpointHtmlRenderer.RenderEndpointComponent(HttpContext httpContext, Type rootComponentType, ParameterView parameters, Boolean waitForQuiescence)
   at Microsoft.AspNetCore.Components.Endpoints.RazorComponentEndpointInvoker.RenderComponentCore(HttpContext context)
   at Microsoft.AspNetCore.Components.Endpoints.RazorComponentEndpointInvoker.RenderComponentCore(HttpContext context)
   at Microsoft.AspNetCore.Components.Endpoints.RazorComponentEndpointInvoker.RenderComponentCore(HttpContext context)
   at Microsoft.AspNetCore.Components.Rendering.RendererSynchronizationContext.<>c.<<InvokeAsync>b__10_0>d.MoveNext()
--- End of stack trace from previous location ---
   at Microsoft.AspNetCore.Diagnostics.ExceptionHandlerMiddlewareImpl.<Invoke>g__Awaited|10_0(ExceptionHandlerMiddlewareImpl middleware, HttpContext context, Task task)
'BlazorServerSideRendering.exe' (CoreCLR: clrhost): Loaded 'Anonymously Hosted DynamicMethods Assembly'. 
Microsoft.AspNetCore.Diagnostics.ExceptionHandlerMiddleware: Error: An exception was thrown attempting to execute the error handler.

System.InvalidOperationException: 'HttpNavigationManager' already initialized.
   at Microsoft.AspNetCore.Components.NavigationManager.Initialize(String baseUri, String uri)
   at Microsoft.AspNetCore.Components.Endpoints.EndpointHtmlRenderer.InitializeStandardComponentServicesAsync(HttpContext httpContext, Type componentType, String handler, IFormCollection form)
   at Microsoft.AspNetCore.Components.Endpoints.RazorComponentEndpointInvoker.RenderComponentCore(HttpContext context)
   at Microsoft.AspNetCore.Components.Rendering.RendererSynchronizationContext.<>c.<<InvokeAsync>b__10_0>d.MoveNext()
--- End of stack trace from previous location ---
   at Microsoft.AspNetCore.Diagnostics.ExceptionHandlerMiddlewareImpl.HandleException(HttpContext context, ExceptionDispatchInfo edi)
Microsoft.AspNetCore.Server.Kestrel: Error: Connection id "0HMT3CPPR7D7F", Request id "0HMT3CPPR7D7F:00000001": An unhandled exception was thrown by the application.

System.Exception: Exception of type 'System.Exception' was thrown.
   at BlazorServerSideRendering.Pages.Index.OnInitialized() in C:\Users\Ben\source\repos\BlazorServerSideRendering\Pages\Index.razor:line 13
   at Microsoft.AspNetCore.Components.ComponentBase.RunInitAndSetParametersAsync()
   at Microsoft.AspNetCore.Components.Rendering.ComponentState.SetDirectParameters(ParameterView parameters)
   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, ArrayRange`1 oldTree, ArrayRange`1 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 Microsoft.AspNetCore.Components.RenderTree.Renderer.ProcessRenderQueue()
   at Microsoft.AspNetCore.Components.RenderTree.Renderer.AddToRenderQueue(Int32 componentId, RenderFragment renderFragment)
   at Microsoft.AspNetCore.Components.ComponentBase.StateHasChanged()
   at Microsoft.AspNetCore.Components.ComponentBase.CallOnParametersSetAsync()
   at Microsoft.AspNetCore.Components.ComponentBase.RunInitAndSetParametersAsync()
   at Microsoft.AspNetCore.Components.Rendering.ComponentState.SetDirectParameters(ParameterView parameters)
   at Microsoft.AspNetCore.Components.RenderTree.Renderer.RenderRootComponentAsync(Int32 componentId, ParameterView initialParameters)
   at Microsoft.AspNetCore.Components.HtmlRendering.Infrastructure.StaticHtmlRenderer.BeginRenderingComponent(IComponent component, ParameterView initialParameters)
   at Microsoft.AspNetCore.Components.Endpoints.EndpointHtmlRenderer.RenderEndpointComponent(HttpContext httpContext, Type rootComponentType, ParameterView parameters, Boolean waitForQuiescence)
   at Microsoft.AspNetCore.Components.Endpoints.RazorComponentEndpointInvoker.RenderComponentCore(HttpContext context)
   at Microsoft.AspNetCore.Components.Endpoints.RazorComponentEndpointInvoker.RenderComponentCore(HttpContext context)
   at Microsoft.AspNetCore.Components.Endpoints.RazorComponentEndpointInvoker.RenderComponentCore(HttpContext context)
   at Microsoft.AspNetCore.Components.Rendering.RendererSynchronizationContext.<>c.<<InvokeAsync>b__10_0>d.MoveNext()
--- End of stack trace from previous location ---
   at Microsoft.AspNetCore.Diagnostics.ExceptionHandlerMiddlewareImpl.<Invoke>g__Awaited|10_0(ExceptionHandlerMiddlewareImpl middleware, HttpContext context, Task task)
   at Microsoft.AspNetCore.Diagnostics.ExceptionHandlerMiddlewareImpl.HandleException(HttpContext context, ExceptionDispatchInfo edi)
   at Microsoft.AspNetCore.Diagnostics.ExceptionHandlerMiddlewareImpl.<Invoke>g__Awaited|10_0(ExceptionHandlerMiddlewareImpl middleware, HttpContext context, Task task)
   at Microsoft.WebTools.BrowserLink.Net.BrowserLinkMiddleware.ExecuteWithFilterAsync(IHttpSocketAdapter injectScriptSocket, String requestId, HttpContext httpContext)
   at Microsoft.AspNetCore.Watch.BrowserRefresh.BrowserRefreshMiddleware.InvokeAsync(HttpContext context)
   at Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Http.HttpProtocol.ProcessRequests[TContext](IHttpApplication`1 application)

Here's the problem inside of that.

System.InvalidOperationException: 'HttpNavigationManager' already initialized.
   at Microsoft.AspNetCore.Components.NavigationManager.Initialize(String baseUri, String uri)
   at Microsoft.AspNetCore.Components.Endpoints.EndpointHtmlRenderer.InitializeStandardComponentServicesAsync(HttpContext httpContext, Type componentType, String handler, IFormCollection form)
   at Microsoft.AspNetCore.Components.Endpoints.RazorComponentEndpointInvoker.RenderComponentCore(HttpContext context)
   at Microsoft.AspNetCore.Components.Rendering.RendererSynchronizationContext.<>c.<<InvokeAsync>b__10_0>d.MoveNext()
--- End of stack trace from previous location ---
   at Microsoft.AspNetCore.Diagnostics.ExceptionHandlerMiddlewareImpl.HandleException(HttpContext context, ExceptionDispatchInfo edi)
Microsoft.AspNetCore.Server.Kestrel: Error: Connection id "0HMT3CPPR7D7F", Request id "0HMT3CPPR7D7F:00000001": An unhandled exception was thrown by the application.

[SteveSandersonMS]

Thanks @benjaminsampica! Now I understand the scenario and have been able to repro it.

On investigation this is a nontrivial thing so I've written up some details at #50287 and will use that to track this. Closing this one now in favour of #50287.