fast-xml-parser/src/xmlparser/node2json.js

Validate XML, Parse XML, Build XML without C/C++ based libraries

'use strict';

import XmlNode from './xmlNode.js';

const METADATA_SYMBOL = XmlNode.getMetaDataSymbol();

/**
 * 
 * @param {array} node 
 * @param {any} options 
 * @returns 
 */
export default function prettify(node, options) {
  return compress(node, options);
}

/**
 * 
 * @param {array} arr 
 * @param {object} options 
 * @param {string} jPath 
 * @returns object
 */
function compress(arr, options, jPath) {
  let text;
  const compressedObj = {}; //This is intended to be a plain object
  for (let i = 0; i < arr.length; i++) {
    const tagObj = arr[i];
    const property = propName(tagObj);
    let newJpath = "";
    if (jPath === undefined) newJpath = property;
    else newJpath = jPath + "." + property;

    if (property === options.textNodeName) {
      if (text === undefined) text = tagObj[property];
      else text += "" + tagObj[property];
    } else if (property === undefined) {
      continue;
    } else if (tagObj[property]) {

      let val = compress(tagObj[property], options, newJpath);
      const isLeaf = isLeafTag(val, options);

      if (tagObj[":@"]) {
        assignAttributes(val, tagObj[":@"], newJpath, options);
      } else if (Object.keys(val).length === 1 && val[options.textNodeName] !== undefined && !options.alwaysCreateTextNode) {
        val = val[options.textNodeName];
      } else if (Object.keys(val).length === 0) {
        if (options.alwaysCreateTextNode) val[options.textNodeName] = "";
        else val = "";
      }

      if (tagObj[METADATA_SYMBOL] !== undefined && typeof val === "object" && val !== null) {
        val[METADATA_SYMBOL] = tagObj[METADATA_SYMBOL]; // copy over metadata
      }


      if (compressedObj[property] !== undefined && Object.prototype.hasOwnProperty.call(compressedObj, property)) {
        if (!Array.isArray(compressedObj[property])) {
          compressedObj[property] = [compressedObj[property]];
        }
        compressedObj[property].push(val);
      } else {
        //TODO: if a node is not an array, then check if it should be an array
        //also determine if it is a leaf node
        if (options.isArray(property, newJpath, isLeaf)) {
          compressedObj[property] = [val];
        } else {
          compressedObj[property] = val;
        }
      }
    }

  }
  // if(text && text.length > 0) compressedObj[options.textNodeName] = text;
  if (typeof text === "string") {
    if (text.length > 0) compressedObj[options.textNodeName] = text;
  } else if (text !== undefined) compressedObj[options.textNodeName] = text;


  return compressedObj;
}

function propName(obj) {
  const keys = Object.keys(obj);
  for (let i = 0; i < keys.length; i++) {
    const key = keys[i];
    if (key !== ":@") return key;
  }
}

function assignAttributes(obj, attrMap, jpath, options) {
  if (attrMap) {
    const keys = Object.keys(attrMap);
    const len = keys.length; //don't make it inline
    for (let i = 0; i < len; i++) {
      const atrrName = keys[i];
      if (options.isArray(atrrName, jpath + "." + atrrName, true, true)) {
        obj[atrrName] = [attrMap[atrrName]];
      } else {
        obj[atrrName] = attrMap[atrrName];
      }
    }
  }
}

function isLeafTag(obj, options) {
  const { textNodeName } = options;
  const propCount = Object.keys(obj).length;

  if (propCount === 0) {
    return true;
  }

  if (
    propCount === 1 &&
    (obj[textNodeName] || typeof obj[textNodeName] === "boolean" || obj[textNodeName] === 0)
  ) {
    return true;
  }

  return false;
}