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node-expat-meteor
Advanced tools
node-expat
Motivation
You use node.js for speed? You process XML streams? Then you want the fastest XML parser: libexpat!
Speed
A stupid speed test is supplied in bench.js. We measure how many
25-byte elements a SAX parser can process:
- node-xml (pure JavaScript): 23,000 el/s
- libxmljs (libxml2 binding): 77,000 el/s
- node-expat (libexpat binding, this): 113,000 el/s
These numbers were recorded on a Core 2 2400 MHz.
Instructions
Install node-expat:
npm i node-expat
Usage
Important events emitted by a parser:
(function () {
"use strict";
var expat = require('node-expat')
, parser
;
parser = new expat.Parser("UTF-8");
parser.on('startElement', function (name, attrs) {
console.log(name, attrs);
});
parser.on('endElement', function (name) {
console.log(name);
});
parser.on('text', function (text) {
console.log(text);
});
parser.on('error', function (err) {
console.error(err);
});
parser.write("<html><head><title>Hello World</title></head><body><p>Foobar</p></body></html>");
}());
Use test.js for reference.
API
#on('startElement' function (name, attrs) {})#on('endElement' function (name) {})#on('text' function (text) {})#on('processingInstruction', function (target, data) {})#on('comment', function (s) {})#on('xmlDecl', function (version, encoding, standalone) {})#on('startCdata', function () {})#on('startCdata', function () {})#on('endCdata', function () {})#on('entityDecl', function (entityName, isParameterEntity, value, base, systemId, publicId, notationName) {})#on('error', function (e) {})#stop()pauses#resume()resumes
Error handling
We don't emit an error event because libexpat doesn't use a callback
either. Instead, check that parse() returns true. A descriptive
string can be obtained via getError() to provide user feedback.
Alternatively, use the Parser like a node Stream. write() will emit
error events.
Namespace handling
A word about special parsing of xmlns: this is not neccessary in a bare SAX parser like this, given that the DOM replacement you are using (if any) is not relevant to the parser.
FAQs
Meteor binding for fast XML parsing.
We found that node-expat-meteor demonstrated a not healthy version release cadence and project activity because the last version was released a year ago. It has 1 open source maintainer collaborating on the project.
Package last updated on 17 Oct 2013
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