It is a tool for transforming html/xml with JS plugins based on cheerio.

npm i postxml --save-dev

var postxml = require('postxml');
var cheerioOptions = {};
var output = postxml([
      require('postxml-plugin')(pluginOptions)
   ])
   .process('<div class="b-block"></div>', cheerioOptions);
);

Use gulp-postxml

var postxml = require('gulp-postxml');
var postxmlPlugins = [
      require('postxml-plugin')(pluginOptions)
   ];
var cheerioOptions = {};
gulp.task('html', function () {
   gulp.src('index.htm')
      .pipe(postxml(postxmlPlugins, cheerioOptions))
      .pipe(gulp.dest('out'));
})

Transform html with plugins

Add plugin

• Plugin Boilerplate

• postxml-amp - converts plain HTML to Google Accelerated Mobile Pages (AMP)
• postxml-beml - BEML plugin
• postxml-custom-tags
• postxml-image-size - adds sizes to images
• postxml-imgalt
• postxml-import
• postxml-import-styles - replace <link> with <style> and import css-code
• postxml-markdown - add classes (bem) to markdown html tags
• postxml-ng-valid - replace ng- with data-ng
• postxml-placeholder
• postxml-remove - removes elements by query selectors
• postxml-repeat - repeat elements
• postxml-wrap - wrap with emmet abbreviation

• postxml-inline-data - replace images and files with data uri
• postxml-template - added template for postxml-repeat
• postxml-lazyload - shortcut syntax for lazyload
• postxml-prefix - add prefix to all classes
• postxml-size - shortcut width & height
• postxml-variables - html variables

• https://github.com/gezatone/gezatone-ui/blob/master/utils/postxml-config.js