update_option is not saving an array, but saving the string 'Array'

Question

I have come across quite an odd problem when using the update_option function, and I am sure that I've tried everything I can think of to get it working, but unfortunately it isn't.

I'm using AJAX to submit a form (using the popular method described here) in the backend, on a custom options page. Everything is working, except for the update_option part. I just don't understand, is there an issue with using that function in an AJAX function callback?

    public function vmAddApp() {
        parse_str( stripslashes( $_POST[ 'data' ] ), $data );
        $nonce = $_POST[ 'nonce' ];
        $app_info = $data[ 'vm_fbconnect' ];
        $option = get_option( 'vm_fbconnect', array() );

        $appId = $data[ 'vm_fbconnect' ][ 'appId' ];
        $secret = $data[ 'vm_fbconnect' ][ 'secret' ];

        $app_response = wp_remote_get( 'https://graph.facebook.com/' . $appId );
        $response_body = json_decode( $app_response[ 'body' ] );
        $app_name = $response_body->name;

        $new_app = array(
            'name' => $app_name,
            'id' => $appId,
            'secret' => $secret
        );
        $option[ 'apps' ][] = $new_app;
        $data = update_option( 'vm_fbconnect', $option );

        // UPDATE:
        // If I put either:
        // $data = $option;  // <- this returns the option correctly, see below
        // or
        // $data = get_option( 'vm_fbconnect', array() );  // <- this returns 'Array' as a string
        // But regardless, both SAVE 'Array' as the option's value..

        header( "content-type: application/json" );
        $response = array( 'data' => $data );
        echo json_encode( $response ); // <- this is how I'm getting the response in the JS console
        exit;
    }

Edit 1: Debugging (I updated the code above, see comments)

This is what I get when I return the modified option from inside the function:

This is what I get when I use get_option again.

After the option has been saved and I am done with the form, sometimes I will go right into the page currently displayed and do die( var_dump( get_option( 'vm_fbconnect', array() ) ); and it says just string(5) 'Array'.

Also, I'm always careful to reset the option before trying each time, and careful to make sure I commented out the delete_option function when trying again! :)

Answer 1

It sounds like your array isn't being serialized before updating the option for whatever reason. Perhaps due to ajax or just your particular situation.

Try this:

// ...

$option[ 'apps' ][] = $new_app;

if( ! is_serialized( $option ) )
    $option = maybe_serialize( $option );

$data = update_option( 'vm_fbconnect', $option );

// ...

Answer 2

Turns out, my question didn't even have to do with AJAX, it had to do with the function used to validate the settings that was supplied with register_setting.

The problem with it was that it wasn't going deep enough into the array to even save the values. I needed to modify it to look like so:

    public function settingsValidate( $todo ) {
        $option = get_option( 'vm_fbconnect', array() );

        if( !empty( $todo ) && is_array( $todo ) ) {
            foreach( $todo as $name => $value ) {
                if( is_array( $value ) ) {
                    foreach( $value as $nam => $val ) {
                        if( is_array( $val ) ) {
                            foreach( $val as $n => $v ) {
                                $option[ $name ][ $nam ][ $n ] = wp_filter_nohtml_kses( $v );
                            }
                        } else {
                            $option[ $name ][ $nam ] = wp_filter_nohtml_kses( $val );
                        }
                    }
                } else {
                    $option[ $name ] = wp_filter_nohtml_kses( $value );
                }
            }
        }

        return $option;
    }

I know there's a better way to do this, will edit sometime later.