Logging

The runner logs through the standard Microsoft.Extensions.Logging abstractions (ILogger<ProcessRunner>), so output flows to whatever providers your host configures — console, Application Insights, Serilog, etc.

What gets logged

Each invocation produces three kinds of log entries:

The invocation line — logged once when the process starts:
```
Run: dotnet build --configuration Release in /repo/src with env CI, NUGET_API_KEY
```
The working directory and environment variables are included only when set. Only the environment variable names are logged, never their values.
Output lines — each stdout line, streamed in real time as the process runs.
Error lines — each stderr line, streamed in real time.

Tuning log levels

All three are configurable per invocation via ProcessRunOptions:

Property	Default	Controls
`InvocationLogLevel`	`Information`	The `Run: …` line.
`OutputLogLevel`	`Debug`	Each stdout line.
`ErrorLogLevel`	`Warning`	Each stderr line.

var options = new ProcessRunOptions("dotnet", "test")
{
    InvocationLogLevel = LogLevel.Debug,   // quieter invocation line
    OutputLogLevel = LogLevel.Information, // show test output at info
    ErrorLogLevel = LogLevel.Error,        // treat stderr lines as errors
};

Use LogLevel.None to suppress a stream from the log entirely.

Note

Log levels only affect logging. The full stdout and stderr are always captured into ProcessRunResult.Output / ProcessRunResult.Error regardless of these settings.

Failure promotion

When a process exits non-zero, quiet output is automatically promoted so the failure is diagnosable from the logs:

stdout configured below Information → re-logged in full at Information;
stderr configured below Information → re-logged in full at Warning.

This happens before the exception is thrown (and also when AllowFailedResult tolerates the failure). The common pattern is therefore:

Leave OutputLogLevel at Debug so successful runs are quiet.
Rely on promotion to surface the full output automatically when something fails.

Secrets in logs

Two things to watch:

The invocation line includes the full command arguments and the names (not values) of any environment variables you set. Prefer passing secrets through EnvironmentVariables; if a secret must go on the command line, lower InvocationLogLevel (or set it to LogLevel.None). The exception thrown on a non-zero exit also includes the full command line.
Output lines may echo secrets printed by the tool. Use TransformOutput / TransformError to redact or suppress them — see Transforming Output.

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