Function maybeRotate

ts/util/rotatingPinoDest.node.ts:45–93

(startingIndex = maxSavedLogFiles - 1)

  };

  function maybeRotate(startingIndex = maxSavedLogFiles - 1) {
    let pendingFileIndex = startingIndex;
    try {
      const { birthtimeMs } = fs.statSync(logFile);

      if (isMoreRecentThan(birthtimeMs, interval)) {
        return;
      }

      for (; pendingFileIndex >= 0; pendingFileIndex -= 1) {
        const currentPath =
          pendingFileIndex === 0 ? logFile : `${logFile}.${pendingFileIndex}`;
        const nextPath = `${logFile}.${pendingFileIndex + 1}`;

        if (fs.existsSync(nextPath)) {
          fs.unlinkSync(nextPath);
        }
        if (!fs.existsSync(currentPath)) {
          continue;
        }
        fs.renameSync(currentPath, nextPath);
      }
    } catch (error) {
      // If we can't access the old log files - try rotating after a small
      // delay.
      if (
        retryCount < MAX_RETRY_COUNT &&
        (error.code === 'EACCES' || error.code === 'EPERM')
      ) {
        retryCount += 1;
        warn(`rotatingPinoDest: retrying rotation, retryCount=${retryCount}`);
        setTimeout(() => maybeRotate(pendingFileIndex), RETRY_DELAY);
        return;
      }

      boom.destroy();
      boom.emit('error', error);
      return;
    }

    // Success, reopen
    boom.reopen();

    if (retryCount !== 0) {
      warn(`rotatingPinoDest: rotation succeeded after ${retryCount} retries`);
    }

    retryCount = 0;
  }

  maybeRotate();
  setInterval(maybeRotate, interval);