Function formatter

packages/core/src/observability/logging.ts:6–21

(id: string = runID)

import { runID } from "./shared"

function formatter(id: string = runID) {
  return Logger.map(Logger.formatStructured, (output) => {
    const messages = Array.isArray(output.message) ? output.message : [output.message]
    return [
      ["timestamp", output.timestamp],
      ["level", output.level],
      ["run", id],
      ...messages.flatMap((value) => (plain(value) ? flatten(value) : [["message", value] as const])),
      ...(output.cause === undefined ? [] : [["cause", output.cause] as const]),
      ...flatten(output.spans),
      ...flatten(output.annotations),
    ]
      .map(([key, value]) => `${key}=${format(value)}`)
      .join(" ")
  })
}

function flatten(
  input: Record<string, unknown>,