aspire: Structured logging support?

[kamranayub]

I'm using IS in a course sample with Aspire + MCP. It's working nicely so far!

I understand I can add Otel traces using ServiceDefaults and referenced the sample. I can see traces in my dashboard:

But, I can't see any structured logs!

You'd think both would work if OTel is enabled. I see structured logs from the MCP SDK:

Am I doing something wrong? I expected it to "just work" so it's a little surprising. IS just uses ILogger right? Doesn't that work out of the box? 🤔

Will update if I figure out what's going on, I'm still an Aspire noob.

Edit 1

One other thing. It feels like the depth of the traces are not reflecting the amount of activities I see in the IS source code.

On external login, shouldn't there be... a lot more activities? I'm new to OTel too, is there like a depth setting or something to control how verbose/deep the trace is? Just looking at how many trace names there should be.

Edit 2

Oh, you need to use wildcard to catch child sources.

[wcabus]

What logging framework are you using? You may need to add an additional NuGet package and wire up the logging framework to also output to your OpenTelemetry endpoints.

For example, Serilog has a NuGet Package Serilog.Sinks.OpenTelemetry, which needs the following line of code to be enabled:

// lc is a LoggerConfiguration instance
lc.WriteTo.OpenTelemetry(); // uses the defaults

// or
lc.WriteTo.OpenTelemetry(options =>
    {
        options.Endpoint = "http://otel-endpoint";
        options.Protocol = OtlpProtocol.HttpProtobuf;
    });

Once configured, you should being to see structured log entries for IdentityServer as well:

[kamranayub]

I started with the duende-is-inmem template, so whatever that uses? I don't think it uses Serilog AFAICT. I thought it would be hooked up! I'll take a look.

[wcabus]

All of our templates use Serilog, so the above should get you up and running :)

[RolandGuijt]

If this helps: I've just updated our Aspire sample to use the latest versions of everything. It also shows how Otel can be configured using Serilog.

[kamranayub]

The problem was that the default is-inmem template had some ConfigureLogging helpers that overrode the ServiceDefaults project. I removed that helper and the Log.Config lines, matched up what the Aspire sample had in ServiceDefaults, and now it's working as expected!