start a module for schema management

lib/schema.php

@@ -0,0 +1,124 @@
+<?php
+/**
+ * Laconica, the distributed open-source microblogging tool
+ *
+ * Database schema utilities
+ *
+ * PHP version 5
+ *
+ * LICENCE: 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 <http://www.gnu.org/licenses/>.
+ *
+ * @category  Database
+ * @package   Laconica
+ * @author    Evan Prodromou <evan@controlyourself.ca>
+ * @copyright 2009 Control Yourself, Inc.
+ * @license   http://www.fsf.org/licensing/licenses/agpl-3.0.html GNU Affero General Public License version 3.0
+ * @link      http://laconi.ca/
+ */
+
+if (!defined('LACONICA')) {
+    exit(1);
+}
+
+/**
+ * Class representing the database schema
+ *
+ * A class representing the database schema. Can be used to
+ * manipulate the schema -- especially for plugins and upgrade
+ * utilities.
+ *
+ * @category Database
+ * @package  Laconica
+ * @author   Evan Prodromou <evan@controlyourself.ca>
+ * @license  http://www.fsf.org/licensing/licenses/agpl-3.0.html GNU Affero General Public License version 3.0
+ * @link     http://laconi.ca/
+ */
+
+class Schema
+{
+    protected $db = null;
+
+    static function get()
+    {
+
+    }
+
+    public function getTableDef($name)
+    {
+    }
+
+    public function getColumnDef($table, $column)
+    {
+    }
+
+    public function getIndexDef($table, $index)
+    {
+    }
+
+    public function createTable($name, $columns, $indices=null)
+    {
+    }
+
+    public function dropTable($name)
+    {
+    }
+
+    public function createIndex($name, $table, $columns)
+    {
+    }
+
+    public function dropIndex($name, $table)
+    {
+    }
+
+    public function addColumn($table, $columndef)
+    {
+    }
+
+    public function modifyColumn($table, $column, $columndef)
+    {
+    }
+
+    public function dropColumn($table, $column)
+    {
+    }
+
+    public function ensureTable($name, $columns, $indices)
+    {
+        $def = $this->tableDef($name);
+        if (empty($def)) {
+            return $this->createTable($name, $columns, $indices);
+        }
+    }
+}
+
+class TableDef
+{
+    public $name;
+    public $columns;
+}
+
+class ColumnDef
+{
+    public $name;
+    public $type;
+    public $size;
+}
+
+class IndexDef
+{
+    public $name;
+    public $table;
+    public $columns;
+}