HTML Validation using Mozilla's HTML5 Validator instance. This is a modified Python file for using the Mozilla Labs' HTML Validator Web Service, located at https://validator.mozillalabs.com/. It was setup in order to be used in the build system of various Mozilla projects, without spamming the main validator (i.e., http://validator.nu)--see https://bugzilla.mozilla.org/show_bug.cgi?id=763804. You can read more about the validator at https://validator.mozillalabs.com/.
You can and should use it in your own Mozilla project's build system in order to automatically check your HTML for errors.
html5check.py -h file.html
You can test the parser with the supplied files:
$ ./html5check.py -h good.html
The document is valid HTML5 + ARIA + SVG 1.1 + MathML 2.0 (subject to the utter previewness of this service).$ ./html5check.py bad.html
Error: Start tag seen without seeing a doctype first. Expected “<!DOCTYPE html>”.
From line 1, column 1; to line 1, column 6
Error: Element “head” is missing a required instance of child element “title”.
From line 3, column 3; to line 3, column 9
Error: An “body” start tag seen but an element of the same type was already open.
From line 5, column 3; to line 5, column 8
Warning: The character encoding of the document was not declared.
There were errors. (Tried in the text/html mode.)
$ ./html5check.py -h good.html- -h : force text/html
- -x : force application/xhtml+xml
- -g : GNU output
- -e : errors only (no info or warnings)
- --encoding=foo : declare encoding foo
- --service=url : the address of the HTML5 validator (defautls to https://validator.mozillalabs.com/)
- node.js client to go with python
- error/warning filtering based on types, categories of errors/warnings