jmkprime

I think I may have something. Following my idea above and keesiemeijer’s point about the comments_template needing a $post object. The methodology is

1. Create a new hidden custom post-type to which the comments are bound.
2. Provide for basic post instance creation.
3. By default the comments for will loop back to the post-types default url and not the referring page. Therefore we need to provide filters for get_comments_link.
4. A wp_rewrite rule addition is needed to deal with paged comments
5. Minimal wrapper to comments_template

The key is creating some sort of deterministic link between a single term and a single post. The following is a proof of concept.

define( 'CAW_TYPE', 'caw_stubb' );

//ACTIONS
add_action( 'init', 'caw_init', 100);

//FILTERS
add_filter( 'get_comment_link', 'caw_comment_link', 1, 3 );

//INIT Function -- setup post type and wp_rewrite riles
function caw_init() {

	$singular = 'Comments Stub';
	$plural = 'Comments Stubs';

	$args = array(
		'label' => $plural,
		'labels' => array( 'name' => $plural, 'singular_name' => $singular, 'add_new' => 'Add '.$singular, 'add_new_item' => 'Add New '.$singular, 'edit_item' => 'Edit '.$singular, 'new_item' => 'New '.$singular, 'view_item' => 'View '.$singular, 'search_items' => 'Search '.$plural, 'not_found' => 'No '.$singular.' found', 'not_found_in_trash' => 'No '.$singular.' found in Trash', 'parent_item_colon' =>  $singular.': ' ),
		'description' => 'Hidden post type used to bind any comment to',
		'public' => false,
		'capability_type' => 'post',
		'supports' => array( 'title', 'trackbacks', 'custom-fields', 'comments' ),
		'query_var' => false
		);

	register_post_type( CAW_TYPE, $args );

	caw_add_rewrite_rules($rules);
}

//ADD wp_rewrite rules for all public taxonomies
function caw_add_rewrite_rules($rules) {
	$taxes = get_taxonomies( array(), 'objects');
	foreach ( $taxes as $tax ) {
		if ( $tax->public ) {
			add_rewrite_rule(
				$tax->rewrite['slug'].'/([^/]+)/comment-page-([0-9]{1,})/?$',
				'index.php?'.$tax->query_var.'=$matches[1]&cpage=$matches[2]',
				'top');
		}
	}
	flush_rewrite_rules();
}

//FILTER get_comments_link to redirect from the hidden post types uri to the uri
//uri of the dynamically generated term page.
function caw_comment_link($link,$comment,$var) {
	global $post;

	if ( get_post_type() == CAW_TYPE ) {
		$meta = get_post_custom();
		$postlink = get_permalink($comment_post_ID);
		$termlink = get_term_link( intval($meta['caw_term_id'][0]), $meta['caw_taxonomy'][0] );
		$link = str_replace( $postlink, $termlink, $link );
	}
	return $link;
}

//RETURN the hidden post associated with a specific term object. Optionally
//create that post if it does not already exist
function caw_getstubb_term($term, $create=true) {
	$oldposts = get_posts( array( 'name' => $term->taxonomy.'-'.$term->term_id, 'post_type' => CAW_TYPE ));
	if ( count($oldposts) == 1 ) {
		return $oldposts[0];
	} elseif ( $create) {
		$newpostid = caw_addstubb_term($term);
		if ( !is_wp_error($newpost) ) {
			return get_post($newpost);
		} else {
			return false;
		}
	} else {
		return false;
	}
}

//CREATE hiiden post associated with a specific term object. Record the parent term using
//the post custom fields
function caw_addstubb_term($term) {

	$newpost = wp_insert_post(
		array(
			'post_title' => $term->name,
			'post_name' => $term->taxonomy.'-'.$term->term_id,
			'post_status' => 'publish',
			'post_type' => CAW_TYPE
			)
		);

	add_post_meta($newpost->ID, 'caw_taxonomy', $term->taxonomy, true);
	add_post_meta($newpost->ID, 'caw_term_id', $term->term_id, true);

	return $newpost;
}

//DISPLAY COMMENTS function. Retrieves hidden post & runs comments_template.
// $file and $seperate are passed directly to comments_template.
function caw_comments_template($term, $file='', $seperate=true, $create=true) {
	global $post, $withcomments;
	if ( isset($post) ) $oldpost = $post;
	$post = caw_getstubb_term($term, $create);
	$withcomments = "1";
	comments_template( $file, $seperate);
	if ( isset($oldpost) ) $post = $oldpost;
}

This is still very generic as it adds the possibility of comments on all public taxonomies. Ideally the creation of the hidden posts would be hooked into the creation/deletion of the original terms. However, I had to do this for a site redesign where those terms were already in
existence.

Further to what Mike posted – one of the options for register_post_type is show_ui, set that to true and WordPress will automatically add the wp-admin menu for you. It’ll also handle all the add, deletion, etc for you.

[Updated to add reference Mike’s post]

I had a problem with identical symptoms – the database upgrade would hang after a certain point. I looked into the code and found that it was the function pre_schema_upgrade() that was hanging. Specifically the MySQL statement:

SELECT o1.option_id FROM $wpdb->options AS o1 JOIN $wpdb->options AS o2 ON o2.option_name = o1.option_name AND o2.option_id > o1.option_id

(line 1685 of wp-admin/includes/upgrade.php)

The upgrade code is looking for duplicated entries in the options database table to remove.

When I ran that request in phpAdmin I got a result with 6 million lines, whereas there were only 400 odd lines with distinct option_name values. I added the work distinct after SELECT on that line forcing it to remove duplicate results. That seemed to work and allowed the upgrade to proceed as usual.

The very quick and dirty way would be to dispense with themes entirely. It’s something I’ve always done – more for lack of time to themeize my site than anything else. What you can do is to put $wp_template_redirect = false; before your call to wp-blog-header.php. That will cause php to continue processing index.php looking for a wp rotor rather than looking in the themes directory.

I then use output escaping

ob_start();
…wp-rotor, etc
$results = ob_get_contents();
ob_end_clean();

to write the output of wordpress to the $results variable. I can then pipe that into my standard site wide template system. In fact I use output buffering several times to capture the various header and sidebar outputs.

It’s not perfect and I really should use themes, but I found that it makes wordpress easier to embed within an existing site.