Quick'n'dirty script to convert a folder of YAML-frontmatter files to JSON-frontmatter

yaml2json.php

<?php

require('vendor/autoload.php');

use Symfony\Component\Yaml\Parser;

$yaml = new Parser();

// Path for the content you want to convert
$files = glob('./micro/*.md');
foreach($files as $file) {

    $post = file_get_contents($file);

    $parts = preg_split('/[\n]*[-]{3}[\n]/', $post, 3);
    if (!empty($parts['1'])) {
        $content = $parts['2'];

        $value = $yaml->parse($parts['1']);

        $json = json_encode($value, JSON_PRETTY_PRINT | JSON_UNESCAPED_SLASHES);

        file_put_contents($file, $json . "\n\n");
        file_put_contents($file, $content, FILE_APPEND);
    } else echo $file . " is not YAML\n";
};

You’ll need to use composer to get this to work. Just one dependency:

$ composer require symfony/yaml