Validate HTML on local machine

I'm currently trying to learn HTML and Java EE Servlet programming. I have an application server running on my local machine (Orion Application Server) and I'm connecting to web pages I've deployed on this server using a browser running on the same machine, directed to http://localhost/mypage.ht开发者_如何转开发m (for example).

I know W3C has a site you can go to that will validate an HTML page (and count how many errors are found for a given doctype), but that has to be a publicly available URL. How do you validate HTML on a locally running setup like I've described above?

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many options:

see installation of w3c validation service:

http://validator.w3.org/docs/install.html

Firefox addons:

Firefox addon or other tool to locally validate HTML pages

https://addons.mozilla.org/en-US/firefox/addon/249/

Offline validator:

http://htmlhelp.com/tools/validator/offline/index.html.en

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You can download a vnu.jar release for checking HTML5 documents offline:

https://github.com/validator/validator/releases/download/latest/vnu.jar

Alternatively, you can install it using any of the following:

• docker run -it --rm -p 8888:8888 ghcr.io/validator/validator:latest
• npm install vnu-jar
• brew install vnu
• pip install html5validator

See https://validator.github.io/validator/ for more details.

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If you're using firefox, this plugin is perfect:

http://users.skynet.be/mgueury/mozilla/

I use it all day. When you view source it shows you a list of errors and highlights them for you.

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A command line tool for validating a folder of html files: https://github.com/svenkreiss/html5validator

It integrates with CircleCI and TravisCI and can be used for validating Pelican and Jekyll sites.

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Perhaps the most straightforward way to do this, is the way I do it all the time. "View source" of the web page, select it all (ctrl+a), choose "copy" (crtl+c), tab over to the validator, and its "direct input" option, and paste it in (ctrl+v). Easy, peasy.

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On Mac, install w3validator by homebrew brew install vnu. Then check your local site by vnu http://localhost/site or any local file by vnu path/to/your/file.html (From Bluu answer)

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If you're using node you may use package html-validator

const validator = require('html-validator')
const fs = require('fs')
var options = {
  format: 'text'
}

fs.readFile( 'file-to-validate.html', 'utf8', (err, html) => {
  if (err) {
    throw err;
  }

  options.data = html

  validator(options)
    .then((data) => {
      console.log(data)
    })
    .catch((error) => {
      console.error(error)
    })
})

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http://validator.w3.org/#validate_by_upload if you don't mind uploading the HTML source file.

http://getfirebug.com/ if you're running Firefox can help with HTML validation issues as well.

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if you have internet connection and want to use https://validator.w3.org/ for localhost without installing, you can use ngrok

reference : https://academy.byidmore.com/post/W3C-Markup-Validation-for-Localhost-5bc942eb3704302c0986bd60

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You can run the tool on your local with docker just by using the command below.

• docker run -it --rm -p 8888:8888 ghcr.io/validator/validator:latest

After running it with docker, when you go to 127.0.0.1:8888 you will see the validator tool. When you try to validate a url and if you get such an error like IO Error (Connection refused) then you can try installing vnu with brew by using the second command below.

• brew install vnu

I tried it with docker and I got IO Error. Then I tried it with brew and it was successful. After you install it with brew, now to check a url you should run the command below.

• vnu http://localhost/page-to-test/

Just replace the url with the one you want to validate with the tool.