Auto-Creating Purchase Orders from Sales Orders

/**
 * @NApiVersion 2.1
 * @NScriptType MapReduceScript
 * Title: MR | Auto-Create POs from Sales Orders
 * Author: The NetSuite Pro
 */
define(['N/search','N/record','N/log'], (search, record, log) => {

  const SEARCH_ID = 'customsearch_so_pending_po';
  const FIELD_PO_CREATED = 'custbody_po_created';

  const getInputData = () => search.load({ id: SEARCH_ID });

  const map = ctx => {
    const soId = JSON.parse(ctx.value).id;
    ctx.write({ key: soId, value: soId });
  };

  const reduce = ctx => {
    const soId = ctx.key;
    try {
      const so = record.load({ type: record.Type.SALES_ORDER, id: soId });
      const subsidiary = so.getValue('subsidiary');
      const entity = so.getValue('entity');

      // Collect lines by vendor
      const vendorMap = {};
      const lineCount = so.getLineCount('item');

      for (let i = 0; i < lineCount; i++) {
        const itemId = so.getSublistValue({ sublistId:'item', fieldId:'item', line:i });
        const qty = so.getSublistValue({ sublistId:'item', fieldId:'quantity', line:i });
        const rate = so.getSublistValue({ sublistId:'item', fieldId:'rate', line:i });
        const vendor = so.getSublistValue({ sublistId:'item', fieldId:'povendor', line:i }); // built-in vendor mapping field

        if (!vendor) continue;
        if (!vendorMap[vendor]) vendorMap[vendor] = [];
        vendorMap[vendor].push({ itemId, qty, rate });
      }

      Object.keys(vendorMap).forEach(vendorId => {
        const po = record.create({
          type: record.Type.PURCHASE_ORDER,
          isDynamic: true
        });
        po.setValue('entity', vendorId);
        po.setValue('subsidiary', subsidiary);
        po.setValue('custbody_linked_salesorder', soId); // optional custom field

        vendorMap[vendorId].forEach(line => {
          po.selectNewLine({ sublistId: 'item' });
          po.setCurrentSublistValue({ sublistId:'item', fieldId:'item', value:line.itemId });
          po.setCurrentSublistValue({ sublistId:'item', fieldId:'quantity', value:line.qty });
          po.setCurrentSublistValue({ sublistId:'item', fieldId:'rate', value:line.rate });
          po.commitLine({ sublistId:'item' });
        });

        const poId = po.save({ enableSourcing:true, ignoreMandatoryFields:false });
        log.audit('PO Created', { vendorId, poId, soId });
      });

      // Flag SO as processed
      record.submitFields({
        type: record.Type.SALES_ORDER,
        id: soId,
        values: { [FIELD_PO_CREATED]: true }
      });

    } catch (e) {
      log.error(`SO ${soId} failed`, e);
    }
  };

  const summarize = summary => {
    log.audit('Auto-PO Summary', {
      usage: summary.usage,
      yields: summary.yields,
      concurrency: summary.concurrency
    });
  };

  return { getInputData, map, reduce, summarize };
});