Struggling to create a custom label parsing syslog output

Grafana Alloy
2

Since I posted this a few days ago and got tagged for potential spam I have since gotten quite a bit further and resolved this particular issue. Specifically I needed the regex group definition I could then import into the labels block. If anyone else comes by with similar struggles here is my current config file for these logs.

// /////////////
// LOGS
// /////////////

// Define which log files to collect for remote_host_logs
local.file_match "remote_host_logs" {
  path_targets = [{
    __address__ = "localhost",
    __path__    = "/var/log/external_logs/*.log",
    instance    = constants.hostname,
    job         = "omada_controller_logs",
  }]
}

// Collect logs from files for remote_host_logs
loki.source.file "remote_host_logs" {
  targets     = local.file_match.remote_host_logs.targets
  forward_to = [loki.process.remote_host_logs_relabels.receiver]
}

// Processing pipeline for remote host logs
loki.process "remote_host_logs_relabels" {
  // Extract all leading fields and the full message ---
  stage.regex {
    expression = "^(?P<log_timestamp_full>\\S+)[[:space:]]+(?P<hostname>\\S+)[[:space:]]+\\s*(?P<internal_event_timestamp>\\S+[[:space:]]+\\S+)\\s*[[:space:]]+(?P<controller_source>.*?)[[:space:]]+-[[:space:]]+-[[:space:]]+-[[:space:]]+(?P<message>.*)"
  }

  // Assign all captured and extracted fields as labels ---
  stage.labels {
    values = {
      log_timestamp_full = "log_timestamp_full",
      hostname = "hostname",
      internal_event_timestamp = "internal_event_timestamp",
      controller_source = "controller_source",
      message = "message",
      operation = "operation",
      details = "details",
    }
  }

  // Forward the processed logs to the Loki write component
  forward_to = [loki.write.to_loki.receiver]
}