Gutenberg Block with Select from JSON-File

Question

I would like to create a block for Gutenberg. I currently have a default configuration:

function my_block_category($categories, $post)
{
    return array_merge(
        $categories,
        array(
            array(
                'slug' => 'my-block',
                'title' => __('BLOCK', 'my-block'),
            ),
        )
    );
}
add_filter('block_categories', 'my_block_category', 10, 2);

function gutenberg_boilerplate_block()
{
    wp_register_script(
        'myblock',
        plugins_url('js/gutenberg' . DIRECTORY_SEPARATOR . 'block.js'),
        array('wp-blocks', 'wp-element')
    );

    register_block_type('myblock/shortcodes', array(
        'editor_script' => 'myblock',
    ));
}
add_action('init', 'gutenberg_boilerplate_block');

It works. I get my category. The goal is that I get a Dropdown Select in my category, which is filled from a JSON file.

{
    "text": {
        "text": "Home",
        "value": "[home]",
        "content": "0"
    },
    ....
}

However, I currently have no idea how I can implement that? The shortcodes that are output are evaluated by the plugin.

Can you tell me how this can be done?