Looking for a Gulp plugin that will skip markdown files based on particular header attributes

Question

I have markdown files that look like this

---
name: Some Name
date: '2013-09-09'
isCool: true
---
really cool text

I want to have a gulp task that only lets markdown through that has a particular property, for example isCool = true.

So I would imagine something like this

gulp.src('source/content/*/*.md')
.pipe(mdPrune({
    isCool: true
}))
.pipe(gulp.dest('build/content/cool'));

then only the markdown that had an isCool attribute in the header would end up the build/content/cool folder.

Answer 1

gulp-filter would work.

const filter = require('gulp-filter');

gulp.task('default', function () {

      // return true if want the file in the stream
  const myFilter = filter(function (file) {

    let contents = file.contents.toString();
    return contents.match('isCool: true');
  });


  return gulp.src(['./src/*.md'])    
    .pipe(myFilter)
    .pipe(gulp.dest('md'));
});

That will allow the file through if isCool: true is anywhere in the file. If that is a problem, just work on the regex to restrict it to the line after the date entry for example.

[The filter could also be defined outside of any task if it might be reused elsewhere or you just prefer it that way.