open-graph-no-thumbnail.php

function fb_opengraph() {

global $post;



if(is_single()) {

if(has_post_thumbnail($post->ID)) {

$img_src = wp_get_attachment_image_src(get_post_thumbnail_id( $post->ID ), 'medium');

} else {

$img_src = get_stylesheet_directory_uri() . 'url-to-your-image-here.jpg';

}

if($excerpt = $post->post_excerpt) {

$excerpt = strip_tags($post->post_excerpt);

$excerpt = str_replace("", "'", $excerpt);

} else {

$excerpt = get_bloginfo('description');

}

?>