<?php $flags = htmlspecialchars(json_encode($posts_array), ENT_QUOTES, "UTF-8"); ?>
<div id="elm" data-flags="<?php echo $flags; ?>"></div>
<!-- Load elm js file here -->
<script>
    var node = document.getElementById("elm");

    var app = Elm.Main.init({
        node: node,
        flags: JSON.parse(node.dataset.flags)
    });
</script>