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I have the following code in my functions.php, which executes a script upon publish:

function save_new_post($post_ID)

    $site_root = '/home/forexmag/public_html/directory2';
    $post = get_post($post_ID);
    $title = $post->post_title;
    $breaking_news = false;

    $categories = get_the_category($post_ID);
    if (is_array($categories) && !empty($categories))
        foreach ($categories as $cat_det)
            //this is the id for the breaking (bad) news
            if (5668 == $cat_det->cat_ID)
                $breaking_news = true;

    $exec_code = "/usr/local/bin/php 
            /crons/cron_notify.php '$title' $post_ID 2 " . intval($breaking_news);

add_action('publish_page', 'save_new_post', 10, 1);

When I publish a new post I keep getting the following error:

Catchable fatal error: Object of class WP_Post could not be converted to string in /home/forexmag/public_html/wp-content/themes/forex_magnates/functions.php on line 712

This line is where I set the $exec_code var. However, as you can see, and as I confirmed via var_dump, the $title variable is a string.

What am I missing?

share|improve this question
Perhaps the problem is $post_ID is an WP_Post not an int. – user27457 Feb 21 '13 at 17:59
Nope. I've confirmed that it is an int – Matanya Feb 21 '13 at 18:01
I don't know why your output looks right, because, as vancoder pointed out, "draft_to_publish" definitely provides a post object and not an ID. wordpress.org/support/topic/… – Jake Feb 21 '13 at 18:51
my bad, I was testing with publish_page. Edited accordingly. Thanks all – Matanya Feb 21 '13 at 19:03
up vote 2 down vote accepted

Magenta is actually correct. $post_ID is a WP_Post object. Your exec code should effectively be using $post_ID->ID.

function save_new_post($post_ID)


WP_Post Object ( [ID] => ...
share|improve this answer
He showed the output of $post_ID, I don't understand why you are so sure. – Jake Feb 21 '13 at 18:20
I'm so sure because I tested it, and I read the codex – vancoder Feb 21 '13 at 18:34
I elaborated on my answer accordingly. – vancoder Feb 21 '13 at 18:42
I see. He is using a set function as part of an existing action. He is definitely using $post_ID wrong in that case. Gotcha. I wasn't paying attention to that action at the bottom... – Jake Feb 21 '13 at 18:46
What I still don't understand is the claim:What's even weirder is that when I var_dump $exec_code and kill the script, I get a perfect string string(121) "/usr/local/bin/php /home/forexmag/public_html/directory2 /crons/cron_notify.php '2011 Free Free Forex Report' 9934 2 0" where 9934 is presumably the post id. Since class WP_Post has no __toString method. How can this be? – user27457 Feb 21 '13 at 18:51

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