The fast-xml-parser npm package is a fast and powerful XML parser and validator that can convert XML to a JavaScript object, JSON, or a traversable JS object. It can also convert a JS object to XML. It is designed to be very fast and efficient, and it provides various options to control the XML parsing and validation process.

What are fast-xml-parser's main functionalities?

XML to JSON Conversion

Converts XML data to a JSON object. The 'parse' function takes an XML string and optional options object, and returns a JSON representation of the XML.

const { parse } = require('fast-xml-parser');
const xmlData = '<note><to>User</to><from>Library</from><heading>Reminder</heading><body>Don't forget to subscribe.</body></note>';
const options = {};
const jsonObj = parse(xmlData, options);

JSON to XML Conversion

Converts a JSON object to an XML string. The 'j2xParser' constructor takes an options object, and the 'parse' method converts the JSON object to an XML string.

const { j2xParser } = require('fast-xml-parser');
const parser = new j2xParser({});
const jsonObj = { note: { to: 'User', from: 'Library', heading: 'Reminder', body: 'Don't forget to subscribe.' } };
const xmlData = parser.parse(jsonObj);

XML Validation

Validates the XML string. The 'validate' function checks if the given XML string is well-formed and returns a validation result.

const { validate } = require('fast-xml-parser');
const xmlData = '<note><to>User</to><from>Library</from></note>';
const validationResult = validate(xmlData);

Traversable Object Creation

Creates a traversable JavaScript object from XML. The 'XMLParser' constructor creates a parser instance, and the 'parse' method converts the XML string into a traversable JS object.

const { XMLParser } = require('fast-xml-parser');
const xmlData = '<note><to>User</to><from>Library</from></note>';
const parser = new XMLParser();
const traversableObject = parser.parse(xmlData);

Other packages similar to fast-xml-parser

fast-xml-parser

Validate XML or Parse XML to JS/JSON very fast without C/C++ based libraries and no callback

You can use this library online (press try me button above), or as command from CLI, or in your website, or in npm repo.

This library let you validate the XML data syntactically.
Or you can transform/covert/parse XML data to JS/JSON object.
Or you can transform the XML in traversable JS object which can later be converted to JS/JSON object.

How to use

Installation

$npm install fast-xml-parser

or using yarn

$yarn add fast-xml-parser

Usage

var fastXmlParser = require('fast-xml-parser');
var jsonObj = fastXmlParser.parse(xmlData);

// when a tag has attributes
var options = {
    attrPrefix : "@_",
    textNodeName : "#text",
    ignoreNonTextNodeAttr : true,
    ignoreTextNodeAttr : true,
    ignoreNameSpace : true,
    textNodeConversion : true
};
if(fastXmlParser.validate(xmlData)=== true){//optional
	var jsonObj = fastXmlParser.parse(xmlData,options);
}

//Intermediate obj
var tObj = fastXmlParser.getTraversalObj(xmlData,options);
var jsonObj = fastXmlParser.convertToJson(tObj);

To use from command line

$xml2js [-ns|-a] <filename> [-o outputfile.json]

To use it on webpage

Download and include parser.js

var isValid = parser.validate(xmlData);
var jsonObj = parser.parse(xmlData);

Give me a star, if you really like this project.

Comparision

I decided to created this library when I couldn't find any library which can convert XML data to json without any callback and which is not based on any C/C++ library.

Libraries that I compared

xml-mapping : fast, result is not satisfactory
xml2js : fast, result is not satisfactory
xml2js-expat : couldn't test performance as it gives error on high load. Installation failed on travis and on my local machine using 'yarn'.
xml2json : based on node-expat which is based on C/C++. Installation failed on travis.
fast-xml-parser : very very fast.

Why not C/C++ based libraries? Installation of such libraries fails on some OS. You may require to install missing dependency manually.

Benchmark report npm_xml2json_compare

Don't forget to check the performance report on comparejs.

validator benchmark: 2000 tps

Limitation

This tool doesn't check if the XML is valid or not. If the XML is not valid you may get invalid result.

Report an issue or request for a feature here

Your contribution in terms of donation, testing, bug fixes, code development etc. can help me to write fast algorithms.

Some of my other NPM pojects

stubmatic : A stub server to mock behaviour of HTTP(s) / REST / SOAP services. Stubbing redis is on the way.
compare js : compare the features of JS code, libraries, and NPM repos.
fast-lorem-ipsum : Generate lorem ipsum words, sentences, paragraph very quickly.

TODO

P2: parser online demo with more options
P2: validator cli
P2: fast XML prettyfier

Keywords

FAQs

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Package last updated on 05 Jun 2017

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Install

fast-xml-parser

What is fast-xml-parser?

What are fast-xml-parser's main functionalities?

Other packages similar to fast-xml-parser

xml2js

xml-js

libxmljs

How to use

Comparision

Limitation

TODO

Keywords

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