What is the best way to get a different post's custom field/postmeta with js?

Question

In gutenberg I want to get a postmeta (it's a json string) that belongs to post #123. I want to check the editor's content against it. Let's say that postmeta's key is "blocks".

So I made this

(function () {
    if (true === window.location.pathname.includes('post.php')) {
        const unsubscribe = window.wp.data.subscribe(function () {
            const arr = JSON.parse('{"first":"1","second":"2"}');

            for (const key in arr) {
                console.log(
                    wp.data
                        .select('core/editor')
                        .getEditedPostContent()
                        .includes(arr[key])
                );
            }
        });
    }
})();

Which works, I can get the content, but I want to replace arr with the json that's in postmetas. Is there a way I can do this with wp.data? I can get current post's metas, but I want post #123's metas.

Answer 1

Here’s a way that could be “best” depending on the circumstance:

const { meta } = wp.data.select( 'core' ).getEntityRecord( 'postType', 'post', 123 );

This tutorial might be helpful for related stuff.