Running parse5 in Linux Mint

03 Jun 2015 . HTML5 . Comments #tutorial

This walkthrough is to install and run parse5 in Linux Mint, 64 bits architecture.

What is parse5

parse5 is a HTML5 parser build in javascript for Node.js or io.js. This is a implementation of the WHATWG specification. The current version is the 4.0.0 and it seems that is currently maintained according to their repository activity.

There are others Html parsers ( htmlparser2,html5 ) but I chose this one because it specifies that is WHATWG html specification compliant, is the one that shows to be alive (github files were updated recently) and because it was tested against the HTML5Lib tests

For more info follow the following links:

https://github.com/inikulin/parse5

https://www.npmjs.com/package/parse5

parse5 is a software for Node.js or io.js. In this walkthrough, I will use Node.js1 which includes npm2 a package manager for javascript. This package manager will help us to download and install parse5 and its dependencies.

Download and install node.js

Download Node.js from their website https://nodejs.org/download/

Install the dependencies. If you don’t do this you are probably get an error like make[1]: g++: Command not found

sudo apt-get install g++ curl libssl-dev apache2-utils
sudo apt-get install git-core

If you don’t do this you are probably get an error like make[1]: g++: Command not found

Then build:

./configure
make
sudo make install

To test is working, do the sever example of the node website :

Write in a example.js file:

var http = require('http');
http.createServer(function (req, res) {
  res.writeHead(200, {'Content-Type': 'text/plain'});
  res.end('Hello World\n');
}).listen(1337, '127.0.0.1');
console.log('Server running at http://127.0.0.1:1337/');
$ node example.js
Server running at http://127.0.0.1:1337/

Once node.js is installed we should have npm installed as well. Lets check version:

$ npm -version
2.10.1

Download and install parse5

Now let npm do this job:

$ npm install parse5

To test it is working lets run the following example, just create a file example.js and copy the code below:

var Parser = require('parse5').Parser;

//Instantiate parser
var parser = new Parser();

//Then feed it with an HTML document
var document = parser.parse('Hello!')

var parse5 =  require('parse5');

//Instantiate new serializer with default tree adapter
var serializer1 = new parse5.Serializer();

//Serialize document
var output = serializer1.serialize(document);

//Show the serialized DOM
console.log(output);

And run it:

$ node example.js 
<html><head></head><body>Hello!</body></html>

As you can see, the malformed html input Hello! was parsed and a correct DOM generated.

Running the html5lib tests

In order to run the html5lib tests, download the source code and test files from their github repository. Lets download the zip and decompress the content.

I got a dependency error when i tried to run the tests:

module.js:338
    throw err;
          ^
Error: Cannot find module 'mocha'
    at Function.Module._resolveFilename (module.js:336:15)
    at Function.Module._load (module.js:278:25)
    at Module.require (module.js:365:17)
    at require (module.js:384:17)

To fix this, install this module with npm install mocha. This module is actually the test framework that help running the tests.

After that run the tests:

$ npm test

> parse5@1.4.2 test /home/jose/HTML5Parsers/parser5_js/parse5-master
> node test/run_tests.js


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  12606 passing (7s)

  1. https://nodejs.org ↩

  2. https://www.npmjs.com/ ↩