リンクをカードにするプラグインを作ろう！(8)DBテーブルにキャッシュする

    function __construct() {
        add_shortcode('blogcard', array($this, 'shortcode' ) );
        add_action('wp_enqueue_scripts', array($this, 'enqueue' ) );
        register_activation_hook(__FILE__, array($this, 'activate') );
    }

function __construct() {

add_shortcode('blogcard', array($this, 'shortcode' ) );

add_action('wp_enqueue_scripts', array($this, 'enqueue' ) );

register_activation_hook(__FILE__, array($this, 'activate') );

}

                $html = '<DIV class="popo_blogcard"><A href="'.$url.'" target="_blank" class="popo_bc_link"><DIV class="popo_bc_wrap"><DIV class="popo_bc_site_name">'.$site_name.'</DIV><DIV class="popo_bc_content"><DIV class="popo_bc_title">'.$title.'</DIV><DIV class="popo_bc_url">'.$url.'</DIV><DIV class="popo_bc_excerpt">'.$excerpt.'</DIV></DIV></DIV></DIV>';
        return $html;
    }
    public function activate() {
    }
    function enqueue() {
        wp_enqueue_style('popo-blogcard', plugin_dir_url(__FILE__).'style.css');
    }

$html = '<DIV class="popo_blogcard"><A href="'.$url.'" target="_blank" class="popo_bc_link"><DIV class="popo_bc_wrap"><DIV class="popo_bc_site_name">'.$site_name.'</DIV><DIV class="popo_bc_content"><DIV class="popo_bc_title">'.$title.'</DIV><DIV class="popo_bc_url">'.$url.'</DIV><DIV class="popo_bc_excerpt">'.$excerpt.'</DIV></DIV></DIV></DIV>';

return $html;

}

public function activate() {

}

function enqueue() {

wp_enqueue_style('popo-blogcard', plugin_dir_url(__FILE__).'style.css');

}

DBのテーブルを作成する

dbDelta()という関数を使ってDBのテーブルを定義します。

    public function activate() {
        global $wpdb;
        $wpdb->hide_errors();
        require_once (ABSPATH.'wp-admin/includes/upgrade.php');
        $sql = "CREATE TABLE ".$wpdb->prefix."popo_blogcard (
                    url              VARCHAR(2048)   DEFAULT '',
                    site_name        VARCHAR(100)    DEFAULT '',
                    title            VARCHAR(200)    DEFAULT '',
                    excerpt          VARCHAR(500)    DEFAULT '',
                ) ".$wpdb->get_charset_collate()." ;";
        dbDelta($sql);
    }

public function activate() {

global $wpdb;

$wpdb->hide_errors();

require_once (ABSPATH.'wp-admin/includes/upgrade.php');

$sql = "CREATE TABLE ".$wpdb->prefix."popo_blogcard (

url VARCHAR(2048) DEFAULT '',

site_name VARCHAR(100) DEFAULT '',

title VARCHAR(200) DEFAULT '',

excerpt VARCHAR(500) DEFAULT '',

) ".$wpdb->get_charset_collate()." ;";

dbDelta($sql);

}

無効化したときに呼ぶ関数

プラグインを停止したときにDBを削除しようと思います。

停止（deactivate）したときに呼ばれる関数を作成します。

    function __construct() {
        add_shortcode('blogcard', array($this, 'shortcode' ) );
        add_action('wp_enqueue_scripts', array($this, 'enqueue' ) );
        register_activation_hook(__FILE__, array($this, 'activate') );
        register_deactivation_hook(__FILE__, array($this, 'deactivate') );
    }

function __construct() {

add_shortcode('blogcard', array($this, 'shortcode' ) );

add_action('wp_enqueue_scripts', array($this, 'enqueue' ) );

register_activation_hook(__FILE__, array($this, 'activate') );

register_deactivation_hook(__FILE__, array($this, 'deactivate') );

}

                ) ".$wpdb->get_charset_collate()." ;";
        dbDelta($sql);
    }
    public function deactivate() {
    }
    function enqueue() {
        wp_enqueue_style('popo-blogcard', plugin_dir_url(__FILE__).'style.css');
    }

) ".$wpdb->get_charset_collate()." ;";

dbDelta($sql);

}

public function deactivate() {

}

function enqueue() {

wp_enqueue_style('popo-blogcard', plugin_dir_url(__FILE__).'style.css');

}

DBのテーブルを削除する

DBのテーブルを削除する記述をします。

    public function deactivate() {
        global $wpdb;
        $sql = "DROP TABLE ".$wpdb->prefix."popo_blogcard";
        $wpdb->query($sql);
    }

public function deactivate() {

global $wpdb;

$sql = "DROP TABLE ".$wpdb->prefix."popo_blogcard";

$wpdb->query($sql);

}

DBのテーブルに情報を書きだす

cURLで取得した「URL」、「サイト名称」、「タイトル」、「概要文」をDBのテーブルに書き出します。

                $site_name = $m['host'];
            }
        }
        curl_close($ch );
        $result = $wpdb->insert(
            $wpdb->prefix.'popo_blogcard',
            array(
                'url' => $url,
                'site_name' => $site_name,
                'title' => $title,
                'excerpt' => $excerpt
            )
        );
        $html = '<DIV class="popo_blogcard"><A href="'.$url.'" target="_blank" class="popo_bc_link"><DIV class="popo_bc_wrap"><DIV class="popo_bc_site_name">'.$site_name.'</DIV><DIV class="popo_bc_content"><DIV class="popo_bc_title">'.$title.'</DIV><DIV class="popo_bc_url">'.$url.'</DIV><DIV class="popo_bc_excerpt">'.$excerpt.'</DIV></DIV></DIV></DIV>';
        return $html;
    }

$site_name = $m['host'];

}

curl_close($ch );

$result = $wpdb->insert(

$wpdb->prefix.'popo_blogcard',

array(

'url' => $url,

'site_name' => $site_name,

'title' => $title,

'excerpt' => $excerpt

)

);

return $html;

}

DBのテーブルから情報を読みだす

DBにキャッシュがあったらcURLでアクセスしないでDBから読み出します。

DBにキャッシュが無い場合の処理を字下げします。

        $url = $opt['url'];
        global $wpdb;
        $data = $wpdb->get_row($wpdb->prepare("SELECT * FROM ".$wpdb->prefix."popo_blogcard WHERE url=%s", $url ) );
        if ($data ) {
            $site_name = $data->site_name;
            $title = $data->title;
            $excerpt = $data->excerpt;
        } else {
            $ch = curl_init($url );
            curl_setopt($ch, CURLOPT_RETURNTRANSFER, true );
            curl_setopt($ch, CURLOPT_TIMEOUT, 8 );
            curl_setopt($ch, CURLOPT_FOLLOWLOCATION, true );
            curl_setopt($ch, CURLOPT_MAXREDIRS, 8 );
            curl_setopt($ch, CURLOPT_AUTOREFERER, true );
            curl_setopt($ch, CURLOPT_COOKIESESSION, true );
            curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false );
            $html = curl_exec($ch );
            if (curl_errno($ch ) ) {
                $site_name = '';
                $title = $url;
                $excerpt = '';
            } else {
                $html = mb_convert_encoding($html, 'UTF-8', 'ASCII,JIS,UTF-8,EUC-JP,SJIS' );
                if (preg_match('/property="og:title"\s*content="([^"]*)/si', $html, $m ) ) {
                    $title = esc_html($m[1]);
                } else {
                    if (preg_match('/<\s*title\s*[^>]*>\s*([^<]*)\s*<\s*\/title\s*[^>]*>/si', $html, $m ) ) {
                        $title = esc_html($m[1]);
                    }
                }
                if (preg_match('/property="og:description"\s*content="([^"]*)/si', $html, $m ) ) {
                    $excerpt = esc_html($m[1]);
                } else {
                    if (preg_match('/name="description"\s*content="([^"]*)/si', $html, $m ) ) {
                        $excerpt = esc_html($m[1]);
                    }
                }
                if (preg_match('/property="og:site_name"\s*content="([^"]*)/si', $html, $m ) ) {
                    $site_name = esc_html($m[1]);
                } else {
                    $m = parse_url($url );
                    $site_name = $m['host'];
                }
            }
            curl_close($ch );
            $result = $wpdb->insert(
                $wpdb->prefix.'popo_blogcard',
                array(
                    'url' => $url,
                    'site_name' => $site_name,
                    'title' => $title,
                    'excerpt' => $excerpt
                )
            );
        }

$url = $opt['url'];

global $wpdb;

$data = $wpdb->get_row($wpdb->prepare("SELECT * FROM ".$wpdb->prefix."popo_blogcard WHERE url=%s", $url ) );

if ($data ) {

$site_name = $data->site_name;

$title = $data->title;

$excerpt = $data->excerpt;

} else {

$ch = curl_init($url );

curl_setopt($ch, CURLOPT_RETURNTRANSFER, true );

curl_setopt($ch, CURLOPT_TIMEOUT, 8 );

curl_setopt($ch, CURLOPT_FOLLOWLOCATION, true );

curl_setopt($ch, CURLOPT_MAXREDIRS, 8 );

curl_setopt($ch, CURLOPT_AUTOREFERER, true );

curl_setopt($ch, CURLOPT_COOKIESESSION, true );

curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false );

$html = curl_exec($ch );

if (curl_errno($ch ) ) {

$site_name = '';

$title = $url;

$excerpt = '';

} else {

$html = mb_convert_encoding($html, 'UTF-8', 'ASCII,JIS,UTF-8,EUC-JP,SJIS' );

if (preg_match('/property="og:title"\s*content="([^"]*)/si', $html, $m ) ) {

$title = esc_html($m[1]);

} else {

if (preg_match('/<\s*title\s*[^>]*>\s*([^<]*)\s*<\s*\/title\s*[^>]*>/si', $html, $m ) ) {

$title = esc_html($m[1]);

}

if (preg_match('/property="og:description"\s*content="([^"]*)/si', $html, $m ) ) {

$excerpt = esc_html($m[1]);

} else {

if (preg_match('/name="description"\s*content="([^"]*)/si', $html, $m ) ) {

$excerpt = esc_html($m[1]);

}

if (preg_match('/property="og:site_name"\s*content="([^"]*)/si', $html, $m ) ) {

$site_name = esc_html($m[1]);

} else {

$m = parse_url($url );

$site_name = $m['host'];

}

curl_close($ch );

$result = $wpdb->insert(

$wpdb->prefix.'popo_blogcard',

array(

'url' => $url,

'site_name' => $site_name,

'title' => $title,

'excerpt' => $excerpt

)

);

}

プラグインを有効化する

プラグインを有効化したときにDBのテーブルを作成するので有効化します。

すでに有効化している場合、いったん停止してから有効化をしてください。

見た目には分かりませんがキャッシュから読み出されるようになりました。

今回のコード

今回はここまでです。

プラグイン本体

<?php
/*
Plugin Name: popo-Blogcard
Plugin URI: https://popozure.info/20180808/13142
Description: Blogcard
Version: 0.0.1
Author: poporon
Author URI: https://popozure.info
License: GPL2
*/
class popo_blogcard {
    function __construct() {
        add_shortcode('blogcard', array($this, 'shortcode' ) );
        add_action('wp_enqueue_scripts', array($this, 'enqueue' ) );
        register_activation_hook(__FILE__, array($this, 'activate') );
        register_deactivation_hook(__FILE__, array($this, 'deactivate') );
    }
    function shortcode($opt , $content = null ) {
        $url = $opt['url'];
        global $wpdb;
        $data = $wpdb->get_row($wpdb->prepare("SELECT * FROM ".$wpdb->prefix."popo_blogcard WHERE url=%s", $url ) );
        if ($data ) {
            $site_name = $data->site_name;
            $title = $data->title;
            $excerpt = $data->excerpt;
        } else {
            $ch = curl_init($url );
            curl_setopt($ch, CURLOPT_RETURNTRANSFER, true );
            curl_setopt($ch, CURLOPT_TIMEOUT, 8 );
            curl_setopt($ch, CURLOPT_FOLLOWLOCATION, true );
            curl_setopt($ch, CURLOPT_MAXREDIRS, 8 );
            curl_setopt($ch, CURLOPT_AUTOREFERER, true );
            curl_setopt($ch, CURLOPT_COOKIESESSION, true );
            curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false );
            $html = curl_exec($ch );
            if (curl_errno($ch ) ) {
                $site_name = '';
                $title = $url;
                $excerpt = '';
            } else {
                $html = mb_convert_encoding($html, 'UTF-8', 'ASCII,JIS,UTF-8,EUC-JP,SJIS' );
                if (preg_match('/property="og:title"\s*content="([^"]*)/si', $html, $m ) ) {
                    $title = esc_html($m[1]);
                } else {
                    if (preg_match('/<\s*title\s*[^>]*>\s*([^<]*)\s*<\s*\/title\s*[^>]*>/si', $html, $m ) ) {
                        $title = esc_html($m[1]);
                    }
                }
                if (preg_match('/property="og:description"\s*content="([^"]*)/si', $html, $m ) ) {
                    $excerpt = esc_html($m[1]);
                } else {
                    if (preg_match('/name="description"\s*content="([^"]*)/si', $html, $m ) ) {
                        $excerpt = esc_html($m[1]);
                    }
                }
                if (preg_match('/property="og:site_name"\s*content="([^"]*)/si', $html, $m ) ) {
                    $site_name = esc_html($m[1]);
                } else {
                    $m = parse_url($url );
                    $site_name = $m['host'];
                }
            }
            curl_close($ch );
            $result = $wpdb->insert(
                $wpdb->prefix.'popo_blogcard',
                array(
                    'url' => $url,
                    'site_name' => $site_name,
                    'title' => $title,
                    'excerpt' => $excerpt
                )
            );
        }
        $html = '<DIV class="popo_blogcard"><A href="'.$url.'" target="_blank" class="popo_bc_link"><DIV class="popo_bc_wrap"><DIV class="popo_bc_site_name">'.$site_name.'</DIV><DIV class="popo_bc_content"><DIV class="popo_bc_title">'.$title.'</DIV><DIV class="popo_bc_url">'.$url.'</DIV><DIV class="popo_bc_excerpt">'.$excerpt.'</DIV></DIV></DIV></DIV>';
        return $html;
    }
    public function activate() {
        global $wpdb;
        $wpdb->hide_errors();
        require_once (ABSPATH.'wp-admin/includes/upgrade.php');
        $sql = "CREATE TABLE ".$wpdb->prefix."popo_blogcard (
                    url              VARCHAR(2048)   DEFAULT '',
                    site_name        VARCHAR(100)    DEFAULT '',
                    title            VARCHAR(200)    DEFAULT '',
                    excerpt          VARCHAR(500)    DEFAULT '',
                ) ".$wpdb->get_charset_collate()." ;";
        dbDelta($sql);
    }
    public function deactivate() {
        global $wpdb;
        $sql = "DROP TABLE ".$wpdb->prefix."popo_blogcard";
        $wpdb->query($sql);
    }
    function enqueue() {
        wp_enqueue_style('popo-blogcard', plugin_dir_url(__FILE__).'style.css');
    }
}
$popo_blogcard = new popo_blogcard;

<?php

Plugin Name: popo-Blogcard

Plugin URI: https://popozure.info/20180808/13142

Description: Blogcard

Version: 0.0.1

Author: poporon

Author URI: https://popozure.info

License: GPL2

class popo_blogcard {

function __construct() {

add_shortcode('blogcard', array($this, 'shortcode' ) );

add_action('wp_enqueue_scripts', array($this, 'enqueue' ) );

register_activation_hook(__FILE__, array($this, 'activate') );

register_deactivation_hook(__FILE__, array($this, 'deactivate') );

}

function shortcode($opt , $content = null ) {

$url = $opt['url'];

global $wpdb;

$data = $wpdb->get_row($wpdb->prepare("SELECT * FROM ".$wpdb->prefix."popo_blogcard WHERE url=%s", $url ) );

if ($data ) {

$site_name = $data->site_name;

$title = $data->title;

$excerpt = $data->excerpt;

} else {

$ch = curl_init($url );

curl_setopt($ch, CURLOPT_RETURNTRANSFER, true );

curl_setopt($ch, CURLOPT_TIMEOUT, 8 );

curl_setopt($ch, CURLOPT_FOLLOWLOCATION, true );

curl_setopt($ch, CURLOPT_MAXREDIRS, 8 );

curl_setopt($ch, CURLOPT_AUTOREFERER, true );

curl_setopt($ch, CURLOPT_COOKIESESSION, true );

curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false );

$html = curl_exec($ch );

if (curl_errno($ch ) ) {

$site_name = '';

$title = $url;

$excerpt = '';

} else {

$html = mb_convert_encoding($html, 'UTF-8', 'ASCII,JIS,UTF-8,EUC-JP,SJIS' );

if (preg_match('/property="og:title"\s*content="([^"]*)/si', $html, $m ) ) {

$title = esc_html($m[1]);

} else {

if (preg_match('/<\s*title\s*[^>]*>\s*([^<]*)\s*<\s*\/title\s*[^>]*>/si', $html, $m ) ) {

$title = esc_html($m[1]);

}

if (preg_match('/property="og:description"\s*content="([^"]*)/si', $html, $m ) ) {

$excerpt = esc_html($m[1]);

} else {

if (preg_match('/name="description"\s*content="([^"]*)/si', $html, $m ) ) {

$excerpt = esc_html($m[1]);

}

if (preg_match('/property="og:site_name"\s*content="([^"]*)/si', $html, $m ) ) {

$site_name = esc_html($m[1]);

} else {

$m = parse_url($url );

$site_name = $m['host'];

}

curl_close($ch );

$result = $wpdb->insert(

$wpdb->prefix.'popo_blogcard',

array(

'url' => $url,

'site_name' => $site_name,

'title' => $title,

'excerpt' => $excerpt

)

);

}

return $html;

}

public function activate() {

global $wpdb;

$wpdb->hide_errors();

require_once (ABSPATH.'wp-admin/includes/upgrade.php');

$sql = "CREATE TABLE ".$wpdb->prefix."popo_blogcard (

url VARCHAR(2048) DEFAULT '',

site_name VARCHAR(100) DEFAULT '',

title VARCHAR(200) DEFAULT '',

excerpt VARCHAR(500) DEFAULT '',

) ".$wpdb->get_charset_collate()." ;";

dbDelta($sql);

}

public function deactivate() {

global $wpdb;

$sql = "DROP TABLE ".$wpdb->prefix."popo_blogcard";

$wpdb->query($sql);

}

function enqueue() {

wp_enqueue_style('popo-blogcard', plugin_dir_url(__FILE__).'style.css');

}

$popo_blogcard = new popo_blogcard;

スタイルシート

.popo_bc_wrap {
    margin: 16px;
    padding: 8px;
    width: 96%;
    border: 2px solid #8888ff;
    background-color: #ffffff;
    border-radius: 3px;
}
.popo_bc_link {
    text-decoration: none;
}
.popo_bc_site_name {
    display: block;
    font-size: 12px;
}
.popo_bc_title {
    display: block;
    font-size: 18px;
    overflow: hidden;
    white-space: nowrap;
    text-overflow: ellipsis;
}
.popo_bc_url {
    display: block;
    font-size: 12px;
    color: #00f;
    text-decoration: underline;
}
.popo_bc_excerpt {
    height: 32px;
    font-size: 12px;
    color: #444;
    overflow: hidden;
    text-overflow: ellipsis;
}

.popo_bc_wrap {

margin: 16px;

padding: 8px;

width: 96%;

border: 2px solid #8888ff;

background-color: #ffffff;

border-radius: 3px;

}

.popo_bc_link {

text-decoration: none;

}

.popo_bc_site_name {

display: block;

font-size: 12px;

}

.popo_bc_title {

display: block;

font-size: 18px;

overflow: hidden;

white-space: nowrap;

text-overflow: ellipsis;

}

.popo_bc_url {

display: block;

font-size: 12px;

color: #00f;

text-decoration: underline;

}

.popo_bc_excerpt {

height: 32px;

font-size: 12px;

color: #444;

overflow: hidden;

text-overflow: ellipsis;

}

次回は･･･

だいたい終わりが見えてきました。

少し寂しいので次回はサムネイルを追加しようと思います。

ぽぽづれ。（このサイト）

リンクをカードにするプラグインを作ろう！(9)サムネイルの追加

https://popozure.info/20180825/13334

画像生成APIを利用してサムネイルを表示します。前回までDBにタイトルや概要文をキャッシュして読み書きしました。サムネイルを取得するWordPress.comの画像生成APIを利用するWordPress.comの画像生成APIを利用します。URLの一部にサムネイルを作りたいURLを組み込み...

では、この辺で。(^-^)o