fast-xml-parser

fast-xml-parser

Validate XML, Parse XML to JS/JSON and vice versa, or parse XML to Nimn rapidly without C/C++ based libraries and no callback

To cover expenses, we're planning to launch FXP Enterprise edition in parallel. Watch it for further updates, if you're interested.

Check ThankYouBackers for our contributors

Users

List of some applications/projects using Fast XML Parser. (Raise an issue to submit yours)

The list of users is collected either from the list published by Github, cummunicated directly through mails/chat , or from other resources. If you feel that your name in the above list is incorrectly published or you're not the user of this library anymore then you can inform us to remove it. We'll do the necessary changes ASAP.

Main Features

• Validate XML data syntactically
• Transform XML to JSON or Nimn
• Transform JSON back to XML
• Works with node packages, in browser, and in CLI (press try me button above for demo)
• Faster than any pure JS implementation.
• It can handle big files (tested up to 100mb).
• Various options are available to customize the transformation
  • You can parse CDATA as a separate property.
  • You can prefix attributes or group them to a separate property. Or they can be ignored from the result completely.
  • You can parse tag's or attribute's value to primitive type: string, integer, float, hexadecimal, or boolean. And can optionally decode for HTML char.
  • You can remove namespace from tag or attribute name while parsing
  • It supports boolean attributes, if configured.

How to use

Installation

To use it as an NPM package:

npm install fast-xml-parser

Or using yarn:

yarn add fast-xml-parser

To use it from a CLI install it globally with the -g option.

npm install fast-xml-parser -g

To use it on a webpage include it from a CDN

XML to JSON

const jsonObj = parser.parse(xmlData [,options] );

const parser = require('fast-xml-parser');
const he = require('he');

const options = {
    attributeNamePrefix : "@_",
    attrNodeName: "attr", //default is 'false'
    textNodeName : "#text",
    ignoreAttributes : true,
    ignoreNameSpace : false,
    allowBooleanAttributes : false,
    parseNodeValue : true,
    parseAttributeValue : false,
    trimValues: true,
    cdataTagName: "__cdata", //default is 'false'
    cdataPositionChar: "\\c",
    parseTrueNumberOnly: false,
    numParseOptions:{
      hex: true,
      leadingZeros: true,
      //skipLike: /\+[0-9]{10}/
    },
    arrayMode: false, //"strict"
    attrValueProcessor: (val, attrName) => he.decode(val, {isAttributeValue: true}),//default is a=>a
    tagValueProcessor : (val, tagName) => he.decode(val), //default is a=>a
    stopNodes: ["parse-me-as-string"],
    alwaysCreateTextNode: false
};

if( parser.validate(xmlData) === true) { //optional (it'll return an object in case it's not valid)
    let jsonObj = parser.parse(xmlData,options);
}

// Intermediate obj
const tObj = parser.getTraversalObj(xmlData,options);
let jsonObj = parser.convertToJson(tObj,options);

As you can notice in the above code, validator is not embedded with in the parser and expected to be called separately. However, you can pass true or validation options as 3rd parameter to the parser to trigger validator internally. It is same as above example.

try{
  let jsonObj = parser.parse(xmlData,options, true);
}catch(error){
  console.log(error.message)
}

Validator returns the following object in case of error;

{
  err: {
    code: code,
    msg: message,
    line: lineNumber,
  },
};

Note: he library is used in this example

$xml2js [-ns|-a|-c|-v|-V] <filename> [-o outputfile.json]
$cat xmlfile.xml | xml2js [-ns|-a|-c|-v|-V] [-o outputfile.json]

const result = parser.validate(xmlData);
if (result !== true) console.log(result.err);
const jsonObj = parser.parse(xmlData);

JSON / JS Object to XML

const Parser = require("fast-xml-parser").j2xParser;
//default options need not to set
const defaultOptions = {
    attributeNamePrefix : "@_",
    attrNodeName: "@", //default is false
    textNodeName : "#text",
    ignoreAttributes : true,
    cdataTagName: "__cdata", //default is false
    cdataPositionChar: "\\c",
    format: false,
    indentBy: "  ",
    supressEmptyNode: false,
    tagValueProcessor: a=> he.encode(a, { useNamedReferences: true}),// default is a=>a
    attrValueProcessor: a=> he.encode(a, {isAttributeValue: isAttribute, useNamedReferences: true}),// default is a=>a
    rootNodeName: "element"
};
const parser = new Parser(defaultOptions);
const xml = parser.parse(json_or_js_obj);

Benchmark

XML to JSON

JSON to XML

Worth to mention

• BigBit standard) : A standard to represent any number in the universe in comparatively less space and without precision loss. A standard to save memory to represent any text string in comparision of UTF encodings.
• imglab : Speedup and simplify image labeling / annotation. Supports multiple formats, one click annotation, easy interface and much more. There are more than half million images are being annotated every month using this tool.
• stubmatic : Create fake webservices, DynamoDB or S3 servers, Manage fake/mock stub data, Or fake any HTTP(s) call.
• अनुमार्गक (anumargak) : The fastest and simple router for node js web frameworks with many unique features.
• मुनीम (Muneem) : A webframework made for all team members. Fast and Featured.
• शब्दावली (shabdawali) : Amazing human like typing effects beyond your imagination.

Contributors

This project exists thanks to all the people who contribute. [Contribute].

Backers

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Sponsors

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License

• MIT License