// Create a Map to store all the data of a Sales Order
Map<String, Object> nsSalesOrder = new Map<String, Object>();
nsSalesOrder.put('internalId', '83943');
nsSalesOrder.put('classification', new Map<String, Object>{'internalId'=>'2'});
nsSalesOrder.put('currencyRecord', new Map<String, Object>{'internalId'=>'1'});
nsSalesOrder.put('department', new Map<String, Object>{'internalId'=>'1'});
nsSalesOrder.put('discountItem', new Map<String, Object>{'internalId'=>'-6'});
nsSalesOrder.put('discountRate', '-20');
nsSalesOrder.put('entity', new Map<String, Object>{'internalId'=>'362'});
nsSalesOrder.put('memo', 'Order 30');
nsSalesOrder.put('otherRefNum', '4343390');
nsSalesOrder.put('tranDate', DateTime.newInstance(2021, 09, 07).getTime()/1000);
// Initialize the Sales Order Custom Fields
List<Object> soCustomFieldList = new List<Object>();
Map<String,Object> soCustomField = new Map<String,Object>();
soCustomField.put('fieldType', 'select');
soCustomField.put('scriptId', 'custbody_customlist');
soCustomField.put('valueLookup', new Map<String,Object>{'internalId'=>'2'});
soCustomFieldList.add(soCustomField);
// Add the Sales Order Custom Fields
nsSalesOrder.put('customFieldList', new Map<String,Object>{'customField'=>soCustomFieldList});
// Initialize the Sales Order Line Items
List<Object> lineItemList = new List<Object>();
Map<String, Object> lineItem = new Map<String, Object>();
lineItem.put('description', 'A weapon for shooting arrows test');
lineItem.put('item', new Map<String, Object>{'internalId'=>'239'});
lineItem.put('amount', 10);
lineItem.put('quantity', 2);
lineItem.put('grossAmt', 220);
lineItem.put('tax1Amt', 210);
lineItem.put('taxRate1', 1);
lineItem.put('revRecEndDate', DateTime.newInstance(2021, 09, 07).getTime()/1000);
lineItem.put('revRecStartDate', DateTime.newInstance(2021, 09, 07).getTime()/1000);
// Initialize the Line Item custom fields
List<Object> liCustomFieldList = new List<Object>();
Map<String, Object> liCustomField = new Map<String, Object>();
liCustomField.put('fieldType', 'boolean');
liCustomField.put('scriptId', 'custbody_checkbox');
liCustomField.put('value', 'true');
liCustomFieldList.add(liCustomField);
// Addg the Sales Order Line Item Custom Fields
lineItem.put('customFieldList',new Map<String,Object>{'customField'=>liCustomFieldList});
lineItemList.add(lineItem);
// Addg the Line Items to Sales Order
Map<String, Object> soLineitemList = new Map<String, Object>();
soLineitemList.put('item',lineItemList);
soLineitemList.put('replaceAll', false);
nsSalesOrder.put('itemList',soLineitemList);
// Initialize the RequestJSON Data to be passed.
Map<String, Object> requestJSONMap = new Map<String, Object>();
requestJSONMap.put('salesOrders', new List<Object>{nsSalesOrder});
String reqJSON = JSON.serialize(requestJSONMap);
Map<String, Object> reqObj = new Map<String, Object>();
reqObj.put('version', '1.0');
reqObj.put('action', 'updateSalesOrder');
reqObj.put('requestJSON', reqJSON);
// Place a request to Breadwinner Global API
Map<String, Object> resp = breadwinner_ns.BreadwinnerNetSuiteAPI.call(reqObj);
System.debug(resp);