We now can define views

src/Database/DBView.php

@@ -0,0 +1,138 @@
+<?php
+/**
+ * @copyright Copyright (C) 2020, Friendica
+ *
+ * @license GNU AGPL version 3 or any later version
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ */
+
+namespace Friendica\Database;
+
+use Exception;
+use Friendica\Core\Hook;
+use Friendica\Core\Logger;
+use Friendica\DI;
+use Friendica\Util\DateTimeFormat;
+use phpDocumentor\Reflection\Types\Boolean;
+
+require_once __DIR__ . '/../../include/dba.php';
+
+class DBView
+{
+	/**
+	 * view definition loaded from config/dbview.config.php
+	 *
+	 * @var array
+	 */
+	private static $definition = [];
+
+	/**
+	 * Loads the database structure definition from the config/dbview.config.php file.
+	 * On first pass, defines DB_UPDATE_VERSION constant.
+	 *
+	 * @see static/dbview.config.php
+	 * @param boolean $with_addons_structure Whether to tack on addons additional tables
+	 * @param string  $basePath              The base path of this application
+	 * @return array
+	 * @throws Exception
+	 */
+	public static function definition($basePath = '', $with_addons_structure = true)
+	{
+		if (!self::$definition) {
+			if (empty($basePath)) {
+				$basePath = DI::app()->getBasePath();
+			}
+
+			$filename = $basePath . '/static/dbview.config.php';
+
+			if (!is_readable($filename)) {
+				throw new Exception('Missing database view config file static/dbview.config.php');
+			}
+
+			$definition = require $filename;
+
+			if (!$definition) {
+				throw new Exception('Corrupted database view config file static/dbview.config.php');
+			}
+
+			self::$definition = $definition;
+		} else {
+			$definition = self::$definition;
+		}
+
+		if ($with_addons_structure) {
+			Hook::callAll('dbview_definition', $definition);
+		}
+
+		return $definition;
+	}
+
+	public static function create(bool $verbose, bool $action)
+	{
+		$definition = self::definition();
+
+		foreach ($definition as $name => $structure) {
+			self::createview($name, $structure, $verbose, $action);
+		}
+	}
+
+	public static function printStructure($basePath)
+	{
+		$database = self::definition($basePath, false);
+
+		foreach ($database AS $name => $structure) {
+			echo "--\n";
+			echo "-- VIEW $name\n";
+			echo "--\n";
+			self::createView($name, $structure, true, false);
+
+			echo "\n";
+		}
+	}
+
+	private static function createview($name, $structure, $verbose, $action)
+	{
+		$r = true;
+
+		$sql_rows = [];
+		foreach ($structure["fields"] AS $fieldname => $origin) {
+			$sql_rows[] = $origin . " AS `" . DBA::escape($fieldname) . "`";
+		}
+
+		$sql = sprintf("DROP VIEW IF EXISTS `%s`", DBA::escape($name));
+
+		if ($verbose) {
+			echo $sql . ";\n";
+		}
+
+		if ($action) {
+			DBA::e($sql);
+		}
+
+		$sql = sprintf("CREATE VIEW `%s` AS SELECT \n\t", DBA::escape($name)) .
+			implode(",\n\t", $sql_rows) . "\n\t" . $structure['query'];
+	
+		if ($verbose) {
+			echo $sql . ";\n";
+		}
+
+		if ($action) {
+			$r = DBA::e($sql);
+		}
+
+		return $r;
+	}
+}