XML-Serializer is a complete JavaScript implementation of the W3C xml serialization specifications. All specifications have been implemented and includes the following specs:
-
[ELEMENT_NODE Serialization]
-
[DOCUMENT_NODE Serialization]
-
[COMMENT_NODE Serialization]
-
[TEXT_NODE Serialization]
-
[DOCUMENT_FRAGMENT_NODE Serialization]
-
[DOCUMENT_TYPE_NODE Serialization]
-
[PROCESSING_INSTRUCTION_NODE Serialization]
This module is available as an npm scoped package and also has a browser build that is located inside the dist
folder. It can easily be integrated with JSDOM for mockup testing.
The below command will install xml-serializer
from npm into your project assuming you have the npm already installed.
Install as a development dependency:
npm install --save-dev @harrison-ifeanyichukwu/xml-serializer
Following the specification, the XMLSerializer
interface is a constructor and has a serializeToString(root)
method exposed on the instance. To serialize any xml node, call the serializeToString(root)
method on a constructed instance, passing in the xml node as like shown below:
import XMLSerializer from '@harrison-ifeanyichukwu/xml-serializer';
let instance = new XMLSerializer();
console.log(instance.serializeToString(someXmlNode));
The constructor can take a boolean argument that indicates if whitespace should be preserved in the serialized output. Default value is true
;
// do not preserve white space
let instance = new XMLSerializer(false);
let xmlString = instance.serializeToString(document);
Using with JSDOM
Currently, JSDOM has not implemented the XMLSerializer
interface. This can be easily integrated with JSDOM and any other similar mockup environment or for web scrapping and xml feed parsing like below.
//assumes jsdom has been installed.
import XMLSerializer from '@harrison-ifeanyichukwu/xml-serializer';
import {JSDOM} from 'jsdom';
let dom = new JSDOM();
dom.window.XMLSerializer = XMLSerializer;
global.window = dom.window;
//start running your tests or do something else.
The browser build is available inside the dist
folder when you npm install the package. You can also this repo and run the build command locally. It exposes an XMLSerializer
construct on the window
object.
<script type="text/javascript" src="node_modules/@harrison-ifeanyichukwu/xml-serializer/dist/main.min.js"><script>
<script type="text/javascript">
let serializer = new XMLSerializer();
// do some serialization stuffs
</script>
By default, the serializer preserves white space during the serialization process. This can be turned off if you want a compact output by passing in false
to the constructor at the time of creating an instance.
//do not preserve white space
let instance = new XMLSerializer(false);
Another improvement is that it removes all duplicate xml prefix definition on as recommended in the specification document unlike what web browsers do. Below is an example of this:
Original XML:
<?xml version="1.0" encoding="utf-8" ?>
<!DOCTYPE root PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<?xml-stylesheet href="classic.css" alternate="yes" title="Classic"
media="screen, print" type="text/css"?>
<!--notice that two namespaces have been defined on the root element-->
<root xmlns:h="http://www.w3.org/TR/html4/" xmlns:f="https://www.w3schools.com/furniture">
<!--notice that it is declared again here. this is a duplicate-->
<h:table xmlns:h="http://www.w3.org/TR/html4/" xmlns:f="https://www.w3schools.com/furniture">
<h:tr>
<h:td>
<h:td>Apples</h:td>
<h:td>Bananas</h:td>
</h:tr>
</h:table>
<!--one is duplicated here-->
<f:table xmlns:f="https://www.w3schools.com/furniture">
<f:name>African Coffee Table</f:name>
<f:width>80</f:width>
<f:length>120</f:length>
</f:table>
<!--html section-->
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta name="description" content="this is html section" />
<base href="http://localhost" />
</head>
<body>
<p>this is a paragraph text</p>
<hr />
<template>
<p>this is a template</p>
</template>
</body>
</html>
<svg:svg xmlns:svg="http://www.w3.org/2000/svg">
<svg:style></svg:style>
<title>my title<title>
</svg:svg>
</root>
Chrome inbuilt XMLSerializer Output:
Notice that all of the duplicated namespaces are removed.
<?xml version="1.0" encoding="utf-8" ?><!DOCTYPE root PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<?xml-stylesheet href="classic.css" alternate="yes" title="Classic"
media="screen, print" type="text/css"?>
<!--notice that two namespaces have been defined on the root element-->
<root xmlns:h="http://www.w3.org/TR/html4/" xmlns:f="https://www.w3schools.com/furniture">
<!--notice that it is declared again here. this is a duplicate-->
<h:table xmlns:h="http://www.w3.org/TR/html4/" xmlns:f="https://www.w3schools.com/furniture">
<h:tr>
<h:td>
<h:td>Apples</h:td>
<h:td>Bananas</h:td>
</h:tr>
</h:table>
<!--one is duplicated here-->
<f:table xmlns:f="https://www.w3schools.com/furniture">
<f:name>African Coffee Table</f:name>
<f:width>80</f:width>
<f:length>120</f:length>
</f:table>
<!--html section-->
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta name="description" content="this is html section" />
<base href="http://localhost" />
</head>
<body>
<p>this is a paragraph text</p>
<hr />
<template>
<p>this is a template</p>
</template>
</body>
</html>
<svg:svg xmlns:svg="http://www.w3.org/2000/svg">
<svg:style></svg:style>
<title>my title<title>
</svg:svg>
</root>
Output of this module:
Notice that all of the duplicated namespaces are removed.
<?xml version="1.0" encoding="utf-8" ?><!DOCTYPE root PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<?xml-stylesheet href="classic.css" alternate="yes" title="Classic"
media="screen, print" type="text/css"?>
<!--notice that two namespaces have been defined on the root element-->
<root xmlns:h="http://www.w3.org/TR/html4/" xmlns:f="https://www.w3schools.com/furniture">
<!--notice that it is declared again here. this is a duplicate-->
<h:table>
<h:tr>
<h:td>
<h:td>Apples</h:td>
<h:td>Bananas</h:td>
</h:tr>
</h:table>
<!--one is duplicated here-->
<f:table>
<f:name>African Coffee Table</f:name>
<f:width>80</f:width>
<f:length>120</f:length>
</f:table>
<!--html section-->
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta name="description" content="this is html section" />
<base href="http://localhost" />
</head>
<body>
<p>this is a paragraph text</p>
<hr />
<template>
<p>this is a template</p>
</template>
</body>
</html>
<svg:svg xmlns:svg="http://www.w3.org/2000/svg">
<svg:style></svg:style>
<title>my title<title>
</svg:svg>
</root>
We welcome your own contributions, ranging from code refactoring, documentation improvements, new feature implementations, bugs/issues reporting, etc. We recommend you follow the steps below to actively contribute to this project:
-
Decide on what to help us with.
-
Fork this repo to your machine.
-
Implement your ideas, and once stable,
-
Create a pull request, explaining your improvements/features
All future contributors will be included below and immensely appreciated. We look forward to your contributions.
This project is maintained by harrison ifeanyichukwu, a young, passionate full stack web developer, an MDN documentator, maintainer of node.js rollup-all project, R-Server (a web server project), and other amazing projects.
He is available for hire, ready to work on PHP
projects, Node.js
projects, React
and Angular
projects and stuffs like that. Looks forward to hearing from you soon!!!
In addition to the spec, the following sections as well as outside resources were consulted and proved very useful:
serialize-doc-type, serialize-xml-attribute, serialize-attr-value, record-element-namespace-info, generate-prefix, xml-character-sets, detect-non-valid-xml-characters