session-desktop/ts/session/apis/snode_api/batchRequest.ts

import { isArray } from 'lodash';
import { Snode } from '../../../data/data';
import { SnodeResponse } from './onions';
import { snodeRpc } from './sessionRpc';
import { NotEmptyArrayOfBatchResults, SnodeApiSubRequests } from './SnodeRequestTypes';

/**
 * This is the equivalent to the batch send on sogs. The target node  runs each sub request and returns a list of all the sub status and bodies.
 * If the global status code is not 200, an exception is thrown.
 * The body is already parsed from json and is enforced to be an Array of at least one element
 * @param subRequests the list of requests to do
 * @param targetNode the node to do the request to, once all the onion routing is done
 * @param timeout
 * @param associatedWith
 * @returns
 */
export async function doSnodeBatchRequest(
  subRequests: Array<SnodeApiSubRequests>,
  targetNode: Snode,
  timeout: number,
  associatedWith?: string
): Promise<NotEmptyArrayOfBatchResults> {
  const result = await snodeRpc({
    method: 'batch',
    params: { requests: subRequests },
    targetNode,
    associatedWith,
    timeout,
  });
  if (!result) {
    window?.log?.warn(
      `doSnodeBatchRequest - sessionRpc could not talk to ${targetNode.ip}:${targetNode.port}`
    );
    throw new Error(
      `doSnodeBatchRequest - sessionRpc could not talk to ${targetNode.ip}:${targetNode.port}`
    );
  }
  const decoded = decodeBatchRequest(result);

  return decoded;
}

/**
 * Make sure the global batch status code is 200, parse the content as json and return it
 */
function decodeBatchRequest(snodeResponse: SnodeResponse): NotEmptyArrayOfBatchResults {
  try {
    if (snodeResponse.status !== 200) {
      throw new Error(`decodeBatchRequest invalid status code: ${snodeResponse.status}`);
    }
    const parsed = JSON.parse(snodeResponse.body);

    if (!isArray(parsed.results)) {
      throw new Error(`decodeBatchRequest results is not an array`);
    }

    if (!parsed.results.length) {
      throw new Error('decodeBatchRequest results an empty array');
    }

    return parsed.results;
  } catch (e) {
    window.log.error('decodeBatchRequest failed with ', e.message);
    throw e;
  }
  // "{"results":[{"body":"retrieve signature verification failed","code":401}]}"
}