Add methods to cache content (for example, on heavy postgres queries)

api/v1/database/mastodon/accounts/search/index.php

@@ -66,7 +66,14 @@ if (isset($_GET['no_statuses']))
 	$sql_all = str_replace('{noStatusesWhere}', '(SELECT count(1) FROM statuses WHERE account_id = a.id) = 0 AND', $sql_all);
 else $sql_all = str_replace('{noStatusesWhere}', '', $sql_all);
 
-$all_accounts = $pg->fetch_all($sql_all);
+
+$cache = null;
+if ($user_filter === 'local')
+	$cache = 'ondemand,60';
+else if (in_array($user_filter, ['all','remote']))
+	$cache = 'ondemand,300';
+
+$all_accounts = $pg->fetch_all($sql_all, $cache);
 
 if (isset($_GET['profile']) && trim($_GET['profile']) != '')
 {
@@ -151,9 +158,9 @@ foreach ($filtered_accounts as $id) {
 		$newacc['avatar'] .= '/accounts/avatars/'.implode('/',$parts).'/original/'.$account['avatar_file_name'];
 	}
 
-	$following = $pg->fetch_one('SELECT count(1) FROM follows WHERE account_id = \''.$id.'\'');
+	$following = $pg->fetch('SELECT count(1) FROM follows WHERE account_id = \''.$id.'\'');
 	$newacc['following'] = intval($following['count']);
-	$followers = $pg->fetch_one('SELECT count(1) FROM follows WHERE target_account_id = \''.$id.'\'');
+	$followers = $pg->fetch('SELECT count(1) FROM follows WHERE target_account_id = \''.$id.'\'');
 	$newacc['followers'] = intval($followers['count']);
 	if (isset($_GET['no_follows']) && $newacc['following'] > 0 && $newacc['followers'] > 0)
 		continue;

base.php

@@ -273,5 +273,49 @@ function normalize_for_search($str) {
 	return trim(implode(' ', $newwords));
 }
 
+function content_cache__exists($key) {
+	$cache_dir = $GLOBALS['appconf']['data_dir'].'/cache';
+	if (!file_exists($cache_dir)) {
+		mkdir($cache_dir);
+		return false;
+	}
+	$key = md5($key);
+	$cache_file = null;
+	foreach (scandir($cache_dir) as $fil) {
+		if (strpos($fil, $key) !== false) {
+			$cache_file = $cache_dir.'/'.$fil;
+			$ps = explode(',',$fil);
+			array_splice($ps, 0, 1);
+			$ps[1] = intval($ps[1]);
+			return (object)[
+				'file' => $cache_file,
+				'config' => $ps
+			];
+		}
+	}
+	return false;
+}
+
+function content_cache__get($key) {
+	$cfg = content_cache__exists($key);
+	if ($cfg === false)
+		return null;
+	$ms = time() - filemtime($cfg->file);
+	if ($cfg->config[0] === 'ondemand' &&
+		$ms > $cfg->config[1]) {
+		unlink($cfg->file);
+		return null;
+	}
+	return unserialize(file_get_contents($cfg->file));
+}
+
+function content_cache__put($key, $config, $data) {
+	$cache_dir = $GLOBALS['appconf']['data_dir'].'/cache';
+	if (!file_exists($cache_dir))
+		mkdir($cache_dir);
+	$cache_file = $cache_dir.'/'.md5($key);
+	file_put_contents($cache_file.','.$config, serialize($data));
+}
+
 // classes
 require 'classes/PgDatabase.php';

classes/PgDatabase.php

@@ -36,18 +36,33 @@ class PgDatabase {
 		return $result;
 	}
 
-	public function fetch_one($sql) {
+	public function fetch($sql, $cache=null) {
+		if ($cache !== null) {
+			$cached = content_cache__get($sql);
+			if ($cached !== null)
+				return $cached;
+		}
 		$result = $this->query($sql);
-		return pg_fetch_assoc($result);
+		$data = pg_fetch_assoc($result);
+		if ($cache !== null)
+			content_cache__put($sql, $cache, $data);
+		return $data;
 	}
 
-	public function fetch_all($sql) {
+	public function fetch_all($sql, $cache=null) {
+		if ($cache !== null) {
+			$cached = content_cache__get($sql);
+			if ($cached !== null)
+				return $cached;
+		}
 		$data = [];
 		$result = $this->query($sql);
 		while ($line = pg_fetch_array($result, null, PGSQL_ASSOC)) {
 			$data []= $line;
 		}
 		pg_free_result($result);
+		if ($cache !== null)
+			content_cache__put($sql, $cache, $data);
 		return $data;
 	}