codysnider / tt-rss

plugins/cache_starred_images/init.php

<?php
class Cache_Starred_Images extends Plugin {

    /* @var PluginHost $host */
    private $host;
    /* @var DiskCache $cache */
    private $cache;
    private $max_cache_attempts = 5; // per-article

    public function about() {
        return array(1.0,
            "Automatically cache media files in Starred articles",
            "fox");
    }

    public function init($host) {
        $this->host = $host;
        $this->cache = new DiskCache("starred-images");

        if ($this->cache->makeDir()) {
                    chmod($this->cache->getDir(), 0777);
        }

        if (!$this->cache->exists(".no-auto-expiry")) {
                    $this->cache->touch(".no-auto-expiry");
        }

        if ($this->cache->isWritable()) {
            $host->add_hook($host::HOOK_HOUSE_KEEPING, $this);
            $host->add_hook($host::HOOK_ENCLOSURE_ENTRY, $this);
            $host->add_hook($host::HOOK_SANITIZE, $this);
        } else {
            user_error("Starred cache directory ".$this->cache->getDir()." is not writable.", E_USER_WARNING);
        }
    }

    public function hook_house_keeping() {
        /* since HOOK_UPDATE_TASK is not available to user plugins, this hook is a next best thing */

        Debug::log("caching media of starred articles for user ".$this->host->get_owner_uid()."...");

        $sth = $this->pdo->prepare("SELECT content, ttrss_entries.title,
       		ttrss_user_entries.owner_uid, link, site_url, ttrss_entries.id, plugin_data
			FROM ttrss_entries, ttrss_user_entries LEFT JOIN ttrss_feeds ON
				(ttrss_user_entries.feed_id = ttrss_feeds.id)
			WHERE ref_id = ttrss_entries.id AND
				marked = true AND
				site_url != '' AND
			    ttrss_user_entries.owner_uid = ? AND
				plugin_data NOT LIKE '%starred_cache_images%'
			ORDER BY ".sql_random_function()." LIMIT 100");

        if ($sth->execute([$this->host->get_owner_uid()])) {

            $usth = $this->pdo->prepare("UPDATE ttrss_entries SET plugin_data = ? WHERE id = ?");

            while ($line = $sth->fetch()) {
                Debug::log("processing article ".$line["title"], Debug::$LOG_VERBOSE);

                if ($line["site_url"]) {
                    $success = $this->cache_article_images($line["content"], $line["site_url"], $line["owner_uid"], $line["id"]);

                    if ($success) {
                        $plugin_data = "starred_cache_images,${line['owner_uid']}:".$line["plugin_data"];

                        $usth->execute([$plugin_data, $line['id']]);
                    }
                }
            }
        }

        /* actual housekeeping */

        Debug::log("expiring ".$this->cache->getDir()."...");

        $files = glob($this->cache->getDir()."/*.{png,mp4,status}", GLOB_BRACE);

        $last_article_id = 0;
        $article_exists = 1;

        foreach ($files as $file) {
            list ($article_id, $hash) = explode("-", basename($file));

            if ($article_id != $last_article_id) {
                $last_article_id = $article_id;

                $sth = $this->pdo->prepare("SELECT id FROM ttrss_entries WHERE id = ?");
                $sth->execute([$article_id]);

                $article_exists = $sth->fetch();
            }

            if (!$article_exists) {
                unlink($file);
            }
        }
    }

    public function hook_enclosure_entry($enc, $article_id) {
        $local_filename = $article_id."-".sha1($enc["content_url"]);

        if ($this->cache->exists($local_filename)) {
            $enc["content_url"] = $this->cache->getUrl($local_filename);
        }

        return $enc;
    }

    public function hook_sanitize($doc, $site_url, $allowed_elements, $disallowed_attributes, $article_id) {
        $xpath = new DOMXpath($doc);

        if ($article_id) {
            $entries = $xpath->query('(//img[@src])|(//video/source[@src])');

            foreach ($entries as $entry) {
                if ($entry->hasAttribute('src')) {
                    $src = rewrite_relative_url($site_url, $entry->getAttribute('src'));

                    $local_filename = $article_id."-".sha1($src);

                    if ($this->cache->exists($local_filename)) {
                        $entry->setAttribute("src", $this->cache->getUrl($local_filename));
                        $entry->removeAttribute("srcset");
                    }
                }
            }
        }

        return $doc;
    }

    private function cache_url($article_id, $url) {
        $local_filename = $article_id."-".sha1($url);

        if (!$this->cache->exists($local_filename)) {
            Debug::log("cache_images: downloading: $url to $local_filename", Debug::$LOG_VERBOSE);

            $data = fetch_file_contents(["url" => $url, "max_size" => MAX_CACHE_FILE_SIZE]);

The constant MAX_CACHE_FILE_SIZE was not found. Maybe you did not declare it correctly or list all dependencies?

            if ($data) {
                            return $this->cache->put($local_filename, $data);
            }
            ;

        } else {
            //Debug::log("cache_images: local file exists for $url", Debug::$LOG_VERBOSE);

            return true;
        }

        return false;
    }

    private function cache_article_images($content, $site_url, $owner_uid, $article_id) {
        $status_filename = $article_id."-".sha1($site_url).".status";

        /* housekeeping might run as a separate user, in this case status/media might not be writable */
        if (!$this->cache->isWritable($status_filename)) {
            Debug::log("status not writable: $status_filename", Debug::$LOG_VERBOSE);
            return false;
        }

        Debug::log("status: $status_filename", Debug::$LOG_VERBOSE);

        if ($this->cache->exists($status_filename)) {
                    $status = json_decode($this->cache->get($status_filename), true);
        } else {
                    $status = [];
        }

        $status["attempt"] += 1;

        // only allow several download attempts for article
        if ($status["attempt"] > $this->max_cache_attempts) {
            Debug::log("too many attempts for $site_url", Debug::$LOG_VERBOSE);
            return false;
        }

        if (!$this->cache->put($status_filename, json_encode($status))) {
            user_error("unable to write status file: $status_filename", E_USER_WARNING);
            return false;
        }

        $doc = new DOMDocument();

        $has_images = false;
        $success = false;

        if ($doc->loadHTML('<?xml encoding="UTF-8">'.$content)) {
            $xpath = new DOMXPath($doc);
            $entries = $xpath->query('(//img[@src])|(//video/source[@src])');

            foreach ($entries as $entry) {

                if ($entry->hasAttribute('src') && strpos($entry->getAttribute('src'), "data:") !== 0) {

                    $has_images = true;

                    $src = rewrite_relative_url($site_url, $entry->getAttribute('src'));

                    if ($this->cache_url($article_id, $src)) {
                        $success = true;
                    }
                }
            }
        }

        $esth = $this->pdo->prepare("SELECT content_url FROM ttrss_enclosures WHERE post_id = ? AND
			(content_type LIKE '%image%' OR content_type LIKE '%video%')");

        if ($esth->execute([$article_id])) {
            while ($enc = $esth->fetch()) {

                $has_images = true;
                $url = rewrite_relative_url($site_url, $enc["content_url"]);

                if ($this->cache_url($article_id, $url)) {
                    $success = true;
                }
            }
        }

        return $success || !$has_images;
    }

    public function api_version() {
        return 2;
    }
}