# grunt-html
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[Grunt][grunt] plugin for HTML validation, using the [Nu Html Checker (v.Nu)][vnujar].
## Getting Started
Install this grunt plugin next to your project's [Gruntfile.js][getting_started] with:
```bash
npm install grunt-html -D
```
Then add this line to your project's `Gruntfile.js`:
```js
grunt.loadNpmTasks('grunt-html');
```
Then specify what files to validate in your config:
```js
grunt.initConfig({
htmllint: {
all: ['demos/**/*.html', 'tests/**/*.html']
}
});
```
For fast validation, keep that in a single group, as the validator initialization takes a few seconds.
When combined with a watching task (such as [grunt-contrib-watch][watch]), even faster validation can be achieved by starting the validator in client mode and connecting to an already-running instance of the validator in server mode. This removes the time required by repeated initializations. See the `server` option below.
## Options
### `errorlevels`
* Type: `Array`
* Default: `['info', 'warning', 'error']`
Set `errorlevels` to control which error types are returned from the validator. Ignores all other returned types.
### `force`
* Type: `Boolean`
* Default: `false`
Set `force` to `true` to report errors but not fail the `grunt` task.
### `ignore`
* Type: `Array`, `String`, or `RegExp`
* Default: `null`
Use this to specify the error message(s) to ignore. For example:
```js
all: {
options: {
ignore: 'The “clear” attribute on the “br” element is obsolete. Use CSS instead.'
},
src: 'html4.html'
}
```
The `ignore` option also supports regular expressions. For example, to ignore AngularJS directive attributes:
```js
all: {
options: {
ignore: /attribute “ng-[a-z-]+” not allowed/
},
src: 'app.html'
}
```
### `noLangDetect`
* Type: `Boolean`
* Default: `false`
Set `noLangDetect` to `true` to [skip the checking of the language of the page](https://github.com/validator/validator#--no-langdetect).
### `reporter`
* Type: `String`
* Default: `null`
Allows you to modify the output format. By default, this plugin will use a built-in Grunt reporter. Set the path to your own custom reporter or to one of the provided reporters: `checkstyle`, `junit` or `json`.
### `reporterOutput`
* Type: `String`
* Default: `null`
Specify a filepath to output the results of a reporter. If `reporterOutput` is specified then all output will be written to the given filepath rather than printed to `stdout`.
### `absoluteFilePathsForReporter`
* Type: `Boolean`
* Default: `false`
Set `absoluteFilePathsForReporter` to `true` to use absolute file paths in generated reports.
### `server`
* Type: `Object`, or a falsy value
* Default: `false`
When `server` is set to a falsy value, the validator is invoked using `java -jar`, which can be considered normal operation.
Set `server` to an object to start the validator in client mode and connect to an already-running instance of the validator in server mode.
To start the validator in server mode, use `java -cp "path/to/vnu.jar" nu.validator.servlet.Main <port>`.
```js
all: {
options: {
// connect to a validator instance running in server mode on localhost:8888
server: {}
},
src: 'app.html'
}
```
The `server` object also accepts the `host` and `port` keys, specifying the location of the server.
```js
all: {
options: {
server: {
// your team's local dev tool machine, for example
host: '192.168.0.5',
port: 8877
}
},
src: 'app.html'
}
```
The following configuration in Gruntfile.js uses [grunt-vnuserver][vnuserver] to start the validator in server mode and sets up a watch task to run `htmllint` every time the source file changes.
By starting the validator in server mode once using the `vnuserver` task, validations by `htmllint` can be performed much faster by simply connecting to this already-running server.
```js
module.exports = function (grunt) {
grunt.initConfig({
vnuserver: {
},
htmllint: {
all: {
options: {
server: {}
},
src: 'app.html'
}
},
watch: {
all: {
tasks: ['htmllint'],
files: 'app.html'
}
}
});
grunt.loadNpmTasks('grunt-vnuserver');
grunt.loadNpmTasks('grunt-html');
grunt.loadNpmTasks('grunt-contrib-watch');
grunt.registerTask('default', ['vnuserver', 'watch']);
};
```
### `threads`
* Type: `String`, `Boolean`, `Number`
* Default: `auto`, which is the number of threads -1
Use this option to control the number of threads that grunt-html will use when validating a big number of files. This will spawn as many Java processes as the number of threads.
## Potential pitfalls
* vnu.jar requires Java 8 environment or up.
## License
Copyright Jörn Zaefferer. Licensed under the [MIT license](LICENSE).
[grunt]: https://gruntjs.com/
[getting_started]: https://gruntjs.com/getting-started
[vnujar]: https://validator.github.io/validator/
[watch]: https://github.com/gruntjs/grunt-contrib-watch
[vnuserver]: https://www.npmjs.com/package/grunt-vnuserver