Is there an existing issue for this?

• I have searched the existing issues

Describe the bug

When you launch a project with Aspire, Aspire adds lots of "OTEL_" environment variables. One of these is "OTEL_EXPORTER_OTLP_PROTOCOL": "grpc" which in my case broke the manual, non-Aspire'y logging I was doing. This was some existing logging code that broke when Aspire was added to the project and the project was launched using the AppHost project.

I am running Seq (https://docs.datalust.co/docs/getting-started) locally and I am using Serilog to export to it using .WriteTo.OpenTelemetry(x =>.... When launching with Aspire, my project logs nothing to Seq. When setting the API project as the start-up project, it works fine.

It was a lot of debugging, but I found the issue by comparing the env variables with and without running with AppHost. No exceptions are thrown so it was an extremely tough error to track down.

Expected Behavior

• I don't really know what the expected behavior should be
• Documentation of this edge case? I think I'd still have run into this problem and it would probably have been hard to find an answer
• Aspire doesn't set this environment variable? I don't know what the consequences of this would be. Is it possible for Aspire to work well with both protocols?
• Aspire's Program.cs allows you/requires you to set the protocol
• Again, not really sure what should be the expected behavior. I guess it was just unexpected that running with AppHost would cause an existing project to break in this way. I don't want to use the Aspire Seq integration just yet and I don't think that should be a requirement personally.

Steps To Reproduce

1. Locally run Seq
2. Have this logging code in your API project's program.cs:

        builder.Host.UseSerilog((context, services, configuration) =>
        {
            configuration
                .Enrich.FromLogContext()
                .Enrich.WithSpan()
                .WriteTo.Console()
                .WriteTo.OpenTelemetry(x =>
                {
                    x.Endpoint = "http://localhost:5341/ingest/otlp/v1/logs";
                    x.Protocol = OtlpProtocol.HttpProtobuf;
                    x.Headers = new Dictionary<string, string>
                    {
                        ["X-Seq-ApiKey"] = "MYAPIKEY"
                    };
                    x.ResourceAttributes = new Dictionary<string, object>
                    {
                        ["service.name"] = "ProfileService.Api"
                    };
                }, true);
        });

3. Launch your app with Aspire AppHost

4. Observe that in Seq, no events are being logged to its dashboard
   

5. In your AppHost's environment variables, add "OTEL_EXPORTER_OTLP_PROTOCOL": "http/protobuf" environment variable.

6. Repeat the above steps and observe that logging is now working again

Exceptions (if any)

No response

.NET Version info

PS C:\Users\RonanBurke> dotnet --info
.NET SDK:
Version: 8.0.403
Commit: c64aa40a71
Workload version: 8.0.400-manifests.e0880c5d
MSBuild version: 17.11.9+a69bbaaf5

Runtime Environment:
OS Name: Windows
OS Version: 10.0.26100
OS Platform: Windows
RID: win-x64
Base Path: C:\Program Files\dotnet\sdk\8.0.403\

.NET workloads installed:
Configured to use loose manifests when installing new manifests.
[android]
Installation Source: SDK 8.0.400, VS 17.11.35327.3
Manifest Version: 34.0.143/8.0.100
Manifest Path: C:\Program Files\dotnet\sdk-manifests\8.0.100\microsoft.net.sdk.android\34.0.143\WorkloadManifest.json
Install Type: FileBased

[aspire]
Installation Source: SDK 8.0.400, VS 17.11.35327.3
Manifest Version: 8.2.2/8.0.100
Manifest Path: C:\Program Files\dotnet\sdk-manifests\8.0.100\microsoft.net.sdk.aspire\8.2.2\WorkloadManifest.json
Install Type: FileBased

[ios]
Installation Source: SDK 8.0.400, VS 17.11.35327.3
Manifest Version: 18.0.8303/8.0.100
Manifest Path: C:\Program Files\dotnet\sdk-manifests\8.0.100\microsoft.net.sdk.ios\18.0.8303\WorkloadManifest.json
Install Type: FileBased

[maccatalyst]
Installation Source: SDK 8.0.400, VS 17.11.35327.3
Manifest Version: 18.0.8303/8.0.100
Manifest Path: C:\Program Files\dotnet\sdk-manifests\8.0.100\microsoft.net.sdk.maccatalyst\18.0.8303\WorkloadManifest.json
Install Type: FileBased

[maui-windows]
Installation Source: SDK 8.0.400, VS 17.11.35327.3
Manifest Version: 8.0.82/8.0.100
Manifest Path: C:\Program Files\dotnet\sdk-manifests\8.0.100\microsoft.net.sdk.maui\8.0.82\WorkloadManifest.json
Install Type: FileBased

[wasm-tools]
Installation Source: VS 17.11.35327.3
Manifest Version: 8.0.10/8.0.100
Manifest Path: C:\Program Files\dotnet\sdk-manifests\8.0.100\microsoft.net.workload.mono.toolchain.current\8.0.10\WorkloadManifest.json
Install Type: FileBased

Host:
Version: 8.0.10
Architecture: x64
Commit: 81cabf2857

.NET SDKs installed:
8.0.403 [C:\Program Files\dotnet\sdk]

.NET runtimes installed:
Microsoft.AspNetCore.App 3.1.32 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.AspNetCore.App 6.0.35 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.AspNetCore.App 8.0.10 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.NETCore.App 3.1.32 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 6.0.35 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 8.0.10 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.WindowsDesktop.App 3.1.32 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
Microsoft.WindowsDesktop.App 6.0.35 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
Microsoft.WindowsDesktop.App 8.0.10 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]

Other architectures found:
x86 [C:\Program Files (x86)\dotnet]
registered at [HKLM\SOFTWARE\dotnet\Setup\InstalledVersions\x86\InstallLocation]

Environment variables:
Not set

global.json file:
Not found

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Anything else?

• ASP.NET Core version: .NET 8
• .NET Aspire version (e.g. package versions): 9.0.0
• The IDE (VS / VS Code / Rider / Other) you're running on, and its version (and any extension versions): Visual Studio 2022 Version 17.11.5