Auto setting post format in my WordPress setup

WordPress with it's custom taxonomy engine has the Post Format option, but it would be much better to do this automatically, wouldn't it? If me as a human can tell the which post is what I just need to translate the logic to PHP.

WordPress with it's custom taxonomy engine has the Post Format1 option, but it would be much better to do this automatically, wouldn't it?

If me as a human can tell the which post is what I just need to translate it to PHP.

Also: post-type-discovery2 is an interesting idea, and though I like Amy's approach3, it's not really what I need. Especially that unlike most of the sites, I have two, different types of picture-based posts: Photo ( made by me ) and Image ( from somewhere else ).

I have a constant here, to make things easier: ARTICLE_MIN_LENGTH is 1100 right now. All my posts are in Markdown, to the regexes are against Markdown formatting.

  • if
    • there is a meta webmention url
    • and a meta webmention type
    • and the webmention type is 'u-in-reply-to'
    • and there is a meta webmention rsvp entry the post is rsvp
  • elseif
    • either
      • there is a meta webmention url
      • and a meta webmention type
      • and the webmention type is 'u-in-reply-to'
      • and there is no meta webmention rsvp entry
    • or
      • the post is imported from Twitter
      • and is a reply to a tweet the post is a reply
  • elseif
    • preg_match "/^```(?:[a-z]+)?/m" is true for the post content, so it has some fenced Markdown code blocks4 the type is article
  • elseif
    • there is a featured image attached
    • and the featured image has EXIF
      • matching any of my cameras
      • OR my name in the copyright field
    • and the post content is at least 90% similar to the image IPTC description ( which I copy for the post content when I upload a photo ) the type is photo
  • elseif
    • the content length is below ARTICLE_MIN_LENGTH
    • and the post has an attached image it an image
  • elseif
    • content is a single url the type is bookmark
  • elseif
    • the content length is below ARTICLE_MIN_LENGTH
    • and the post content preg_match "/(?:www\.)?youtube\.com\/watch\?v=[a-zA-Z0-9_-]+/" the type is video
  • elseif
    • the content length is below ARTICLE_MIN_LENGTH
    • and the post content preg_match "/\[audio.*\]/" the type is audio
  • elseif
    • the content length is below ARTICLE_MIN_LENGTH
    • and the post content preg_match "/^> /m" the type is quote
  • elseif
    • the post title is empty
    • or
      • content length is below ARTICLE_MIN_LENGTH
      • and the post has the category 'blips' the format is note
  • else it's an article

It's not perfect yet, but I'm getting there.

In PHP, including all helper functions ( this is not a copy-paste code; it will probably break if you do that ):

<?php

define('ARTICLE_MIN_LENGTH', 1100);
define('CACHE_EXPIRE', 300);

function post_format ( &$post ) {
    if (empty($post) || !is_object($post) || !isset($post->ID))
        return false;

    if ( $cached = wp_cache_get ( $post->ID, __FUNCTION__ ) )
        return $cached;

    $slug = 'article';
    $name = __('Article', 'petermolnareu');

    $post_length = strlen( $post->post_content );

    $webmention_url = get_post_meta( $post->ID, 'webmention_url', true );
    $webmention_type = get_post_meta( $post->ID, 'webmention_type', true );
    $webmention_rsvp = get_post_meta( $post->ID, 'webmention_rsvp', true );

    $links = extract_urls($post->post_content);
    $content = $post->post_content;

    if (!empty($links) && count($links) == 1) {
        // one single link in the post, so it's most probably a bookmark
        $webmention_url = $links[0];
        $content = str_replace($webmention_url, '', $content);
        $content = trim($content);
    }

    $is_twitter_reply = is_twitter_reply($post);

    // /m for multiline, so ^ means beginning of line
    $has_quote = preg_match("/^> /m", $post->post_content);

    // /m for multiline, so ^ means beginning of line
    $has_code = preg_match("/^```(?:[a-z]+)?/m", $post->post_content);

    $diff = 0;
    $has_thumbnail = get_post_thumbnail_id( $post->ID );
    if ( $has_thumbnail ) {
        $thumbnail_meta = get_extended_meta( $has_thumbnail );
        if (isset($thumbnail_meta['image_meta']['caption']) && !empty($thumbnail_meta['image_meta']['caption'])) {
            similar_text( $post->post_content, $thumbnail_meta['image_meta']['caption'], $diff);
        }
    }

    $has_youtube = preg_match("/(?:www\.)?youtube\.com\/watch\?v=[a-zA-Z0-9_-]+/", $post->post_content);

    $has_audio = preg_match("/\[audio.*\]/", $post->post_content);

    $has_blips = has_category( 'blips', $post );


    /**
     * Actual discovery
     */
    if ( !empty($webmention_url) && !empty($webmention_type) && $webmention_type == 'u-in-reply-to' && !empty($webmention_rsvp) ) {
        $slug = 'rsvp';
        $name =  __('Response to event','petermolnareu');
    }
    elseif ( (!empty($webmention_url) && !empty($webmention_type) && $webmention_type == 'u-in-reply-to') || $is_twitter_reply ) {
        $slug = 'reply';
        $name = __('Reply','petermolnareu');
    }
    elseif ( $has_code ) {
        $slug = 'article';
        $name = __('Article', 'petermolnareu');
    }
    elseif ( $has_thumbnail && static::is_photo($has_thumbnail) && $diff > 90 ) {
        $slug = 'photo';
        $name =  __('Photo','petermolnareu');
    }
    elseif ( $post_length < ARTICLE_MIN_LENGTH && $has_thumbnail ) {
        $slug = 'image';
        $name = __('Image','petermolnareu');
    }
    elseif ( !empty($webmention_url) && empty($content)) {
        $slug = 'bookmark';
        $name = __('Bookmark','petermolnareu');
    }
    elseif ( $post_length < ARTICLE_MIN_LENGTH && $has_youtube ) {
        $slug = 'video';
        $name = __('Video','petermolnareu');
    }
    elseif ( $post_length < ARTICLE_MIN_LENGTH && $has_audio ) {
        $slug = 'audio';
        $name = __('Audio','petermolnareu');
    }
    elseif ( $post_length < ARTICLE_MIN_LENGTH && $has_quote ) {
        $slug = 'quote';
        $name = __('Quote','petermolnareu');
    }
    elseif ( strlen($post->post_title) == 0 || ($post_length < ARTICLE_MIN_LENGTH && $has_blips) ) {
        $slug = 'note';
        $name = __('Note','petermolnareu');
    }

    wp_cache_set ( $post->ID, $slug, __FUNCTION__, CACHE_EXPIRE );
    return $slug;
}

function is_photo (&$thid) {
    if ( empty($thid))
        return false;

    if ( $cached = wp_cache_get ( $thid, __FUNCTION__ ) )
        return $cached;

    $return = false;

    $rawmeta = wp_get_attachment_metadata( $thid );

    if ( isset( $rawmeta['image_meta'] ) && !empty($rawmeta['image_meta'])) {

        if (isset($rawmeta['image_meta']['copyright']) && !empty($rawmeta['image_meta']['copyright']) && ( stristr($rawmeta['image_meta']['copyright'], 'Peter Molnar') || stristr($rawmeta['image_meta']['copyright'], 'petermolnar.eu'))) {
            $return = true;
        }

        $my_devs = array ( 'PENTAX K-5 II s', 'NIKON D80' );
        if ( isset($rawmeta['image_meta']['camera']) && !empty($rawmeta['image_meta']['camera']) && in_array(trim($rawmeta['image_meta']['camera']), $my_devs)) {
            $return = true;
        }
    }

    wp_cache_set ( $thid, $return, __FUNCTION__, CACHE_EXPIRE );

    return $return;
}


function get_extended_meta ( &$thid ) {
    if ( empty ( $thid ) )
        return false;

    if ( $cached = wp_cache_get ( $thid, __FUNCTION__ ) )
        return $cached;

    $attachment = get_post( $thid );

    $meta = array();
    if ( if (empty($attachment) || !is_object($attachment) || !isset($attachment->ID))) {
        $meta = wp_get_attachment_metadata($thid);

        if ( !empty ( $attachment->post_parent ) ) {
            $parent = get_post( $attachment->post_parent );
            $meta['parent'] = $parent->ID;
        }

        $src = wp_get_attachment_image_src ($thid, 'full');
        $meta['src'] = $src[0];

        if (isset($meta['sizes']) && !empty($meta['sizes'])) {
            foreach ( $meta['sizes'] as $size => $data ) {
                $src = wp_get_attachment_image_src ($thid, $size);
                $meta['sizes'][$size]['src'] = $src;
            }
        }

        if ( empty($meta['image_meta']['title']))
            $meta['image_meta']['title'] = esc_attr($attachment->post_title);

        $slug = sanitize_title ( $meta['image_meta']['title'] , $thid );
        if ( is_numeric( substr( $slug, 0, 1) ) )
            $slug = 'img-' . $slug;
        $meta['image_meta']['slug'] = $slug;

        $meta['image_meta']['alt'] = '';
        $alt = get_post_meta($thid, '_wp_attachment_image_alt', true);
        if ( !empty($alt))
            $meta['image_meta']['alt'] = strip_tags($alt);
    }

    wp_cache_set ( $thid, $meta, __FUNCTION__, CACHE_EXPIRE );

    return $meta;
}

function is_twitter_reply( &$post ) {
    if ( $cached = wp_cache_get ( $post->ID, __FUNCTION__ ) )
        return $cached;

    $r = false;

    $twitter_in_reply_to_screen_name = get_post_meta ( $post->ID, 'twitter_in_reply_to_screen_name', true);
    if (!empty($twitter_in_reply_to_screen_name)) {
            $r = true;
    }

    $twitter_reply_id = get_post_meta ($post->ID, 'twitter_reply_id', true);
    if (!empty($twitter_reply_id)) {
        $r = true;
    }

    wp_cache_set ( $post->ID, $r, __FUNCTION__, CACHE_EXPIRE );
    return $r;
}

// this is mainly for Markdown, HTML may fail
function extract_urls( &$text ) {
    $matches = array();
    preg_match_all("/\b(?:http|https)\:\/\/?[a-zA-Z0-9\.\/\?\:@\-_=#]+\.[a-zA-Z0-9\.\/\?\:@\-_=#]*/i", $text, $matches);

    $matches = $matches[0];
    return $matches;
}

(Oh, by the way: this entry was written by Peter Molnar, and originally posted on petermolnar dot net.)

⋅ CC-BY-4.0 ⋅ ⋅ https://petermolnar.net/article/wordpress-post-format-discovery/

This post elsewhere on the web: archive.org

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