Open graph 'image' content appears empty on debugger and filled in web source

Question

Defining Open Graph meta tags like this for images.

global $post; 
$postImg = wp_get_attachment_image_src( get_post_thumbnail_id($post->ID), array( 1200, 9999 ), false );
<meta property="og:image" content="<?php echo $postImg[0]; ?>"/>
<meta property="og:image:width" content="<?php echo $postImg[1]; ?>"/>
<meta property="og:image:height" content="<?php echo $postImg[2]; ?>"/>

I get this in my website source:

<meta property="og:image" content="http://elpace.co/event-image.jpg"/>  
<meta property="og:image:width" content="2953"/>    
<meta property="og:image:height" content="4134"/>   

But this in facebook's Open Graph debugger (what scrapper sees).

<meta property="og:image" content="">
<meta property="og:image:width" content="">
<meta property="og:image:height" content="">

Thank You

Answer 1

The problem was using scheduled pots with $post->post_status => 'future'. Scheduled posts can be tricky to handle.

So, the solution is to trick them into being $post->post_status => 'publish' when saved, as shown in this answer:

Marking future dated post as published

Answer 2

wp_get_attachment_image_url is not returning the good image size. The function need the name of the image size or a valid image size (1200 x 9999 is not a valid size, just the the way to tell add_image_size cropping definition).

Then the scrapper will be able to scrappe your content. If think there is a minimum and maximum size, and your size seems to be a little bit heavy. Hope it helps you.