Alloy emits invalid logfmt with level = "debug"

[IngmarStein]

What's wrong?

I've configured Alloy to emit debug logs:

logging {
    level = "debug"
    format = "logfmt" 
}

This results in log entries like this:

ts=2025-04-30T11:31:48.998669Z level=debug msg="extracted data debug in logfmt stage" component_path=/ component_id=loki.process.local_logs component=stage type=logfmt "extracted data"="map[filename:/opt/homebrew/var/log/grafana-alloy.log hostname:homelab.localdomain job:grafana-alloy ts:2025-04-30T11:31:48.812936Z]"

Note the extracted data key in quotes which is invalid according to https://docs.appsignal.com/logging/formatting/logfmt.html: "Keys cannot contain spaces, but may contain fullstops (.), underscores (_) and hyphens (-)."

Alloy subsequently fails to decode its own output: ts=2025-04-30T11:31:48.998709Z level=error msg="failed to decode logfmt" component_path=/ component_id=loki.process.local_logs component=stage type=logfmt err="logfmt syntax error at pos 169 on line 1: unexpected '\"'"

Steps to reproduce

Process Alloy debug logs in a loki.process component with a stage.logfmt like this:

    stage.logfmt {
        mapping = {
            "ts" = "",
        }
    }

System information

No response

Software version

No response

Configuration

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