@sap/hdbext/lib/sp/wrap-params.js

Hana-client extension library and utility functions for using SAP HANA in node.js

'use strict';

var debug = require('debug')('hdbext:sp');
var isInput = require('./utils').isInput;
var isInputTable = require('./utils').isInputTable;

module.exports = function wrapProcedureParams(metadata, arrArgs) {
  debug('Input length: %s', arrArgs.length);

  if (usingNamedParams(arrArgs)) {
    debug('Creating named parameters');
    return new NamedParams(arrArgs[0]);
  }

  if (usingArrayWithParams(metadata, arrArgs)) {
    debug('Creating positioned parameters from an array with input arguments');
    return new PositionedParams(metadata, arrArgs[0]);
  }

  debug('Creating positioned parameters from comma-separated input arguments');
  return new PositionedParams(metadata, arrArgs);
};

function usingNamedParams(arrArgs) {
  if (arrArgs.length !== 1) {
    return false;
  }
  var arg = arrArgs[0];
  return typeof arg === 'object' && arg !== null &&
    !Array.isArray(arg) && !Buffer.isBuffer(arg) && !Object.prototype.hasOwnProperty.call(arg, 'table');
}

function usingArrayWithParams(metadata, arrArgs) {
  if (arrArgs.length !== 1 || !Array.isArray(arrArgs[0])) {
    return false;
  }

  var inputParams = metadata.filter(isInput);

  if (inputParams.length === 1 && isInputTable(inputParams[0])) {
    debug('Procedure has only one input parameter which is an input table parameter');
    return false;
  }

  return true;
}


function NamedParams(nameToValue) {
  this._params = nameToValue;
}

NamedParams.prototype.getAll = function () {
  return this._params;
};

NamedParams.prototype.has = function (name) {
  return name in this._params;
};

NamedParams.prototype.get = function (name) {
  return this._params[name];
};

NamedParams.prototype.empty = function () {
  return Object.keys(this._params).length === 0;
};


function PositionedParams(metadata, arr) {
  this._params = arr;
  this._nameToPosition = {};

  var paramPosition = 0;
  metadata.filter(isInput).forEach(function (paramMeta) {
    this._nameToPosition[paramMeta.PARAMETER_NAME] = paramPosition++;
  }, this);
}

PositionedParams.prototype.getAll = function () {
  return this._params;
};

PositionedParams.prototype.has = function (name) {
  var paramPosition = this._nameToPosition[name];
  return this._params.length > paramPosition;
};

PositionedParams.prototype.get = function (name) {
  var position = this._nameToPosition[name];
  return this._params[position];
};

PositionedParams.prototype.empty = function () {
  return this._params.length === 0;
};