Installing W3C Markup Validator on Debian Jessie

The W3C Markup Validator is a useful tool that allows validating html text. It can be used to check if a given web page or text conforms to the html 5 standard. The following points may be considered during installation of W3C markup validator:

• local copy of validator is more reliable and easy to use for bulk use
• W3C Markup Validator supports validation of html,xml, xhtml, html5, mathml and more
• html5 validation requires validator.nu installation
• deb file not available in default repository for Debian Jessie
• W3C Markup Validator has to be installed from source. install guide given on: https://validator.w3.org/docs/install.html
• install guide for mod_perl from source (https://perl.apache.org/docs/2.0/user/install/install.html
• following perl module had to be installed: SGML-Parser-OpenSP
• libperl-dev package required for mod_perl compilation (http://tara24.de/fix-configure-errorperl-development-headers-found/)
• java 8 required for validator.nu
• java 8 for debian jessie requires backport repository (http://backports.debian.org/Instructions/)