Anyone had any success sending messages to Azure IOT Hub from a WASM application?

[hbraasch]

Anyone had any success sending messages to Azure IOT Hub from a WASM application?

My code works fine for the other platforms, but when running under WASM, it throws the System.PlatformNotSupportedException: Operation is not supported on this platform. exception when doing a Microsoft.Azure.Devices send.

I could not find any guidance searching through Uno Issues/Discussions.

Checking Github it acknowledges the complexities, but before going down that rabbit hole with possible AI hallucinations...

Can someone please help in case there's a working solution?

Help shall be much appreciated.

[jeromelaban]

Thanks for the question.

We haven't done IOT Hub integrations in the Uno team, but given the specific error that you're getting, it's likely that the package that you're using may need an update specifically for wasm. Could you share the full stack trace of the exception?

[hbraasch]

The trace is:

[MONO] Process terminated.
[MONO] ThreadPool.BackgroundJobHandler failed

Unhandled Exception:
System.PlatformNotSupportedException: Operation is not supported on this platform.
   at System.Net.Http.SocketsHttpHandler.get_SslOptions() in D:\a\Uno.DotnetRuntime.WebAssembly\Uno.DotnetRuntime.WebAssembly\runtime\src\libraries\System.Net.Http\src\System\Net\Http\BrowserHttpHandler\SocketsHttpHandler.cs:line 117
   at Microsoft.Azure.Devices.HttpClientHelper.CreateDefaultHttpMessageHandler(IWebProxy webProxy, Uri baseUri, Int32 connectionLeaseTimeoutMilliseconds)
   at Microsoft.Azure.Devices.HttpClientHelper.CreateDefaultClient(IWebProxy webProxy, Uri baseUri, Int32 connectionLeaseTimeoutMilliseconds)
   at Microsoft.Azure.Devices.HttpClientHelper..ctor(Uri baseAddress, IAuthorizationHeaderProvider authenticationHeaderProvider, IReadOnlyDictionary`2 defaultErrorMapping, TimeSpan timeout, IWebProxy customHttpProxy, Int32 connectionLeaseTimeoutMilliseconds)
   at Microsoft.Azure.Devices.ServiceClient..ctor(IotHubConnectionProperties connectionProperties, Boolean useWebSocketOnly, ServiceClientTransportSettings transportSettings, ServiceClientOptions options)
   at Microsoft.Azure.Devices.ServiceClient.CreateFromConnectionString(String connectionString, TransportType transportType, ServiceClientTransportSettings transportSettings, ServiceClientOptions options)
   at Microsoft.Azure.Devices.ServiceClient.CreateFromConnectionString(String connectionString, TransportType transportType, ServiceClientOptions options)
   at Microsoft.Azure.Devices.ServiceClient.CreateFromConnectionString(String connectionString, ServiceClientOptions options)
   at IotHubTester2.Models.DirectMessengerAzureIotClient.Connect() in C:\Users\Heinrich\source\repos\IotHubTester2\IotHubTester2\Models\DirectMessengerAzureIotClient.cs:line 52
   at IotHubTester2.Presentation.MainViewModel.ConnectToIotHubCommand() in C:\Users\Heinrich\source\repos\IotHubTester2\IotHubTester2\Presentation\MainViewModel.cs:line 35
   at CommunityToolkit.Mvvm.Input.AsyncRelayCommand.AwaitAndThrowIfFailed(Task executionTask) in /_/src/CommunityToolkit.Mvvm/Input/AsyncRelayCommand.cs:line 351
   at System.Threading.Tasks.Task.<>c.<ThrowAsync>b__128_1(Object state) in D:\a\Uno.DotnetRuntime.WebAssembly\Uno.DotnetRuntime.WebAssembly\runtime\src\libraries\System.Private.CoreLib\src\System\Threading\Tasks\Task.cs:line 1929
   at System.Threading.QueueUserWorkItemCallbackDefaultContext.Execute() in D:\a\Uno.DotnetRuntime.WebAssembly\Uno.DotnetRuntime.WebAssembly\runtime\src\libraries\System.Private.CoreLib\src\System\Threading\ThreadPoolWorkQueue.cs:line 1266
   at System.Threading.ThreadPoolWorkQueue.Dispatch() in D:\a\Uno.DotnetRuntime.WebAssembly\Uno.DotnetRuntime.WebAssembly\runtime\src\libraries\System.Private.CoreLib\src\System\Threading\ThreadPoolWorkQueue.cs:line 913
   at System.Threading.ThreadPool.BackgroundJobHandler() in D:\a\Uno.DotnetRuntime.WebAssembly\Uno.DotnetRuntime.WebAssembly\runtime\src\mono\System.Private.CoreLib\src\System\Threading\ThreadPool.Browser.Mono.cs:line 130
Aborted()
RuntimeError: Aborted(). Build with -sASSERTIONS for more info.
Stack trace:
 >  at abort (http://localhost:5000/package_dcfd50348c14863b98a01db586afc106558de65e/dotnet.native.js:8:9137)
 >    at _abort (http://localhost:5000/package_dcfd50348c14863b98a01db586afc106558de65e/dotnet.native.js:8:97733)
 >    at http://localhost:5000/package_dcfd50348c14863b98a01db586afc106558de65e/dotnet.native.wasm:wasm-function[1787]:0x97b09
 >    at http://localhost:5000/package_dcfd50348c14863b98a01db586afc106558de65e/dotnet.native.wasm:wasm-function[1828]:0x99414
 >    at http://localhost:5000/package_dcfd50348c14863b98a01db586afc106558de65e/dotnet.native.wasm:wasm-function[354]:0x20314
 >    at http://localhost:5000/package_dcfd50348c14863b98a01db586afc106558de65e/dotnet.native.wasm:wasm-function[250]:0x1c426
 >    at http://localhost:5000/package_dcfd50348c14863b98a01db586afc106558de65e/dotnet.native.wasm:wasm-function[243]:0xf4b5
 >    at http://localhost:5000/package_dcfd50348c14863b98a01db586afc106558de65e/dotnet.native.wasm:wasm-function[311]:0x1ef9d
 >    at http://localhost:5000/package_dcfd50348c14863b98a01db586afc106558de65e/dotnet.native.wasm:wasm-function[332]:0x1f79f
 >    at http://localhost:5000/package_dcfd50348c14863b98a01db586afc106558de65e/dotnet.native.wasm:wasm-function[222]:0xd201

I think it's a CORS issue, but I do not know if one can enable CORS on the IOT hub. I'm hoping someone might have solved it by now.

Thanks for the help. Much appreciated.

[jeromelaban]

Thanks. This is not a CORS issue, this is really because the ServiceClient is trying to change unsupported options on the HttpMessageHandler.

By the looks of the stack, it's likely that you can change the HttpMessageHandler builder (CreateDefaultHttpMessageHandler suggests that there's a way to override it). You may want to create your own handler without the call that does not work on Wasm.