Function createLightweightSummary

worker/src/temporal/utils/component-output.ts:149–199

(
  component: RegisteredComponent,
  output: unknown,
)

 * This avoids sending huge payloads over Kafka.
 */
export function createLightweightSummary(
  component: RegisteredComponent,
  output: unknown,
): Record<string, unknown> {
  if (!output || typeof output !== 'object' || Array.isArray(output)) {
    return { _value: output } as any;
  }

  const obj = output as Record<string, unknown>;
  const summary: Record<string, unknown> = {};
  let hasTruncatedContent = false;

  // Copy summary field if it exists
  if (obj.summary) {
    summary.summary = obj.summary;
  }

  for (const [key, value] of Object.entries(obj)) {
    // Skip internal fields
    if (key.startsWith('__')) continue;
    if (key === 'summary') continue;

    if (Array.isArray(value)) {
      summary[`${key}Count`] = value.length;
      hasTruncatedContent = true;
    } else if (value !== null && typeof value === 'object') {
      // Nested objects are summarized if they have a summary, otherwise just marked as truncated
      if ((value as any).summary) {
        summary[key] = { summary: (value as any).summary, _truncated: true };
      }
      hasTruncatedContent = true;
    } else {
      // Primitives (string, number, boolean, null)
      summary[key] = value;
    }
  }

  // If output was already a spilled marker, preserve its metadata
  if (obj.__spilled__) {
    summary.__spilled__ = true;
    summary.storageRef = obj.storageRef;
    summary.originalSize = obj.originalSize;
    hasTruncatedContent = true;
  }

  if (hasTruncatedContent) {
    summary._truncated = true;
  }

  return summary;
}