forked from GNUsocial/gnu-social
		
	
		
			
				
	
	
		
			501 lines
		
	
	
		
			12 KiB
		
	
	
	
		
			PHP
		
	
	
	
	
	
			
		
		
	
	
			501 lines
		
	
	
		
			12 KiB
		
	
	
	
		
			PHP
		
	
	
	
	
	
| <?php
 | |
| /**
 | |
|  * StatusNet, 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   StatusNet
 | |
|  * @author    Evan Prodromou <evan@status.net>
 | |
|  * @copyright 2009 StatusNet, Inc.
 | |
|  * @license   http://www.fsf.org/licensing/licenses/agpl-3.0.html GNU Affero General Public License version 3.0
 | |
|  * @link      http://status.net/
 | |
|  */
 | |
| 
 | |
| if (!defined('STATUSNET')) {
 | |
|     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  StatusNet
 | |
|  * @author   Evan Prodromou <evan@status.net>
 | |
|  * @license  http://www.fsf.org/licensing/licenses/agpl-3.0.html GNU Affero General Public License version 3.0
 | |
|  * @link     http://status.net/
 | |
|  */
 | |
| 
 | |
| class Schema
 | |
| {
 | |
|     static $_static = null;
 | |
|     protected $conn = null;
 | |
| 
 | |
|     /**
 | |
|      * Constructor. Only run once for singleton object.
 | |
|      */
 | |
| 
 | |
|     protected function __construct($conn = null)
 | |
|     {
 | |
|         if (is_null($conn)) {
 | |
|             // XXX: there should be an easier way to do this.
 | |
|             $user = new User();
 | |
|             $conn = $user->getDatabaseConnection();
 | |
|             $user->free();
 | |
|             unset($user);
 | |
|         }
 | |
| 
 | |
|         $this->conn = $conn;
 | |
|     }
 | |
| 
 | |
|     /**
 | |
|      * Main public entry point. Use this to get
 | |
|      * the schema object.
 | |
|      *
 | |
|      * @return Schema the Schema object for the connection
 | |
|      */
 | |
| 
 | |
|     static function get($conn = null)
 | |
|     {
 | |
|         if (is_null($conn)) {
 | |
|             $key = 'default';
 | |
|         } else {
 | |
|             $key = md5(serialize($conn->dsn));
 | |
|         }
 | |
|         
 | |
|         $type = common_config('db', 'type');
 | |
|         if (empty(self::$_static[$key])) {
 | |
|             $schemaClass = ucfirst($type).'Schema';
 | |
|             self::$_static[$key] = new $schemaClass($conn);
 | |
|         }
 | |
|         return self::$_static[$key];
 | |
|     }
 | |
| 
 | |
|     /**
 | |
|      * Gets a ColumnDef object for a single column.
 | |
|      *
 | |
|      * Throws an exception if the table is not found.
 | |
|      *
 | |
|      * @param string $table  name of the table
 | |
|      * @param string $column name of the column
 | |
|      *
 | |
|      * @return ColumnDef definition of the column or null
 | |
|      *                   if not found.
 | |
|      */
 | |
| 
 | |
|     public function getColumnDef($table, $column)
 | |
|     {
 | |
|         $td = $this->getTableDef($table);
 | |
| 
 | |
|         foreach ($td->columns as $cd) {
 | |
|             if ($cd->name == $column) {
 | |
|                 return $cd;
 | |
|             }
 | |
|         }
 | |
| 
 | |
|         return null;
 | |
|     }
 | |
| 
 | |
|     /**
 | |
|      * Creates a table with the given names and columns.
 | |
|      *
 | |
|      * @param string $name    Name of the table
 | |
|      * @param array  $columns Array of ColumnDef objects
 | |
|      *                        for new table.
 | |
|      *
 | |
|      * @return boolean success flag
 | |
|      */
 | |
| 
 | |
|     public function createTable($name, $columns)
 | |
|     {
 | |
|         $uniques = array();
 | |
|         $primary = array();
 | |
|         $indices = array();
 | |
| 
 | |
|         $sql = "CREATE TABLE $name (\n";
 | |
| 
 | |
|         for ($i = 0; $i < count($columns); $i++) {
 | |
| 
 | |
|             $cd =& $columns[$i];
 | |
| 
 | |
|             if ($i > 0) {
 | |
|                 $sql .= ",\n";
 | |
|             }
 | |
| 
 | |
|             $sql .= $this->_columnSql($cd);
 | |
| 
 | |
|             switch ($cd->key) {
 | |
|             case 'UNI':
 | |
|                 $uniques[] = $cd->name;
 | |
|                 break;
 | |
|             case 'PRI':
 | |
|                 $primary[] = $cd->name;
 | |
|                 break;
 | |
|             case 'MUL':
 | |
|                 $indices[] = $cd->name;
 | |
|                 break;
 | |
|             }
 | |
|         }
 | |
| 
 | |
|         if (count($primary) > 0) { // it really should be...
 | |
|             $sql .= ",\nconstraint primary key (" . implode(',', $primary) . ")";
 | |
|         }
 | |
| 
 | |
|         foreach ($uniques as $u) {
 | |
|             $sql .= ",\nunique index {$name}_{$u}_idx ($u)";
 | |
|         }
 | |
| 
 | |
|         foreach ($indices as $i) {
 | |
|             $sql .= ",\nindex {$name}_{$i}_idx ($i)";
 | |
|         }
 | |
| 
 | |
|         $sql .= "); ";
 | |
| 
 | |
|         $res = $this->conn->query($sql);
 | |
| 
 | |
|         if (PEAR::isError($res)) {
 | |
|             throw new Exception($res->getMessage());
 | |
|         }
 | |
| 
 | |
|         return true;
 | |
|     }
 | |
| 
 | |
|     /**
 | |
|      * Drops a table from the schema
 | |
|      *
 | |
|      * Throws an exception if the table is not found.
 | |
|      *
 | |
|      * @param string $name Name of the table to drop
 | |
|      *
 | |
|      * @return boolean success flag
 | |
|      */
 | |
| 
 | |
|     public function dropTable($name)
 | |
|     {
 | |
|         $res = $this->conn->query("DROP TABLE $name");
 | |
| 
 | |
|         if (PEAR::isError($res)) {
 | |
|             throw new Exception($res->getMessage());
 | |
|         }
 | |
| 
 | |
|         return true;
 | |
|     }
 | |
| 
 | |
|     /**
 | |
|      * Adds an index to a table.
 | |
|      *
 | |
|      * If no name is provided, a name will be made up based
 | |
|      * on the table name and column names.
 | |
|      *
 | |
|      * Throws an exception on database error, esp. if the table
 | |
|      * does not exist.
 | |
|      *
 | |
|      * @param string $table       Name of the table
 | |
|      * @param array  $columnNames Name of columns to index
 | |
|      * @param string $name        (Optional) name of the index
 | |
|      *
 | |
|      * @return boolean success flag
 | |
|      */
 | |
| 
 | |
|     public function createIndex($table, $columnNames, $name=null)
 | |
|     {
 | |
|         if (!is_array($columnNames)) {
 | |
|             $columnNames = array($columnNames);
 | |
|         }
 | |
| 
 | |
|         if (empty($name)) {
 | |
|             $name = "$table_".implode("_", $columnNames)."_idx";
 | |
|         }
 | |
| 
 | |
|         $res = $this->conn->query("ALTER TABLE $table ".
 | |
|                                    "ADD INDEX $name (".
 | |
|                                    implode(",", $columnNames).")");
 | |
| 
 | |
|         if (PEAR::isError($res)) {
 | |
|             throw new Exception($res->getMessage());
 | |
|         }
 | |
| 
 | |
|         return true;
 | |
|     }
 | |
| 
 | |
|     /**
 | |
|      * Drops a named index from a table.
 | |
|      *
 | |
|      * @param string $table name of the table the index is on.
 | |
|      * @param string $name  name of the index
 | |
|      *
 | |
|      * @return boolean success flag
 | |
|      */
 | |
| 
 | |
|     public function dropIndex($table, $name)
 | |
|     {
 | |
|         $res = $this->conn->query("ALTER TABLE $table DROP INDEX $name");
 | |
| 
 | |
|         if (PEAR::isError($res)) {
 | |
|             throw new Exception($res->getMessage());
 | |
|         }
 | |
| 
 | |
|         return true;
 | |
|     }
 | |
| 
 | |
|     /**
 | |
|      * Adds a column to a table
 | |
|      *
 | |
|      * @param string    $table     name of the table
 | |
|      * @param ColumnDef $columndef Definition of the new
 | |
|      *                             column.
 | |
|      *
 | |
|      * @return boolean success flag
 | |
|      */
 | |
| 
 | |
|     public function addColumn($table, $columndef)
 | |
|     {
 | |
|         $sql = "ALTER TABLE $table ADD COLUMN " . $this->_columnSql($columndef);
 | |
| 
 | |
|         $res = $this->conn->query($sql);
 | |
| 
 | |
|         if (PEAR::isError($res)) {
 | |
|             throw new Exception($res->getMessage());
 | |
|         }
 | |
| 
 | |
|         return true;
 | |
|     }
 | |
| 
 | |
|     /**
 | |
|      * Modifies a column in the schema.
 | |
|      *
 | |
|      * The name must match an existing column and table.
 | |
|      *
 | |
|      * @param string    $table     name of the table
 | |
|      * @param ColumnDef $columndef new definition of the column.
 | |
|      *
 | |
|      * @return boolean success flag
 | |
|      */
 | |
| 
 | |
|     public function modifyColumn($table, $columndef)
 | |
|     {
 | |
|         $sql = "ALTER TABLE $table MODIFY COLUMN " .
 | |
|           $this->_columnSql($columndef);
 | |
| 
 | |
|         $res = $this->conn->query($sql);
 | |
| 
 | |
|         if (PEAR::isError($res)) {
 | |
|             throw new Exception($res->getMessage());
 | |
|         }
 | |
| 
 | |
|         return true;
 | |
|     }
 | |
| 
 | |
|     /**
 | |
|      * Drops a column from a table
 | |
|      *
 | |
|      * The name must match an existing column.
 | |
|      *
 | |
|      * @param string $table      name of the table
 | |
|      * @param string $columnName name of the column to drop
 | |
|      *
 | |
|      * @return boolean success flag
 | |
|      */
 | |
| 
 | |
|     public function dropColumn($table, $columnName)
 | |
|     {
 | |
|         $sql = "ALTER TABLE $table DROP COLUMN $columnName";
 | |
| 
 | |
|         $res = $this->conn->query($sql);
 | |
| 
 | |
|         if (PEAR::isError($res)) {
 | |
|             throw new Exception($res->getMessage());
 | |
|         }
 | |
| 
 | |
|         return true;
 | |
|     }
 | |
| 
 | |
|     /**
 | |
|      * Ensures that a table exists with the given
 | |
|      * name and the given column definitions.
 | |
|      *
 | |
|      * If the table does not yet exist, it will
 | |
|      * create the table. If it does exist, it will
 | |
|      * alter the table to match the column definitions.
 | |
|      *
 | |
|      * @param string $tableName name of the table
 | |
|      * @param array  $columns   array of ColumnDef
 | |
|      *                          objects for the table
 | |
|      *
 | |
|      * @return boolean success flag
 | |
|      */
 | |
| 
 | |
|     public function ensureTable($tableName, $columns)
 | |
|     {
 | |
|         // XXX: DB engine portability -> toilet
 | |
| 
 | |
|         try {
 | |
|             $td = $this->getTableDef($tableName);
 | |
|         } catch (Exception $e) {
 | |
|             if (preg_match('/no such table/', $e->getMessage())) {
 | |
|                 return $this->createTable($tableName, $columns);
 | |
|             } else {
 | |
|                 throw $e;
 | |
|             }
 | |
|         }
 | |
| 
 | |
|         $cur = $this->_names($td->columns);
 | |
|         $new = $this->_names($columns);
 | |
| 
 | |
|         $toadd  = array_diff($new, $cur);
 | |
|         $todrop = array_diff($cur, $new);
 | |
|         $same   = array_intersect($new, $cur);
 | |
|         $tomod  = array();
 | |
| 
 | |
|         foreach ($same as $m) {
 | |
|             $curCol = $this->_byName($td->columns, $m);
 | |
|             $newCol = $this->_byName($columns, $m);
 | |
| 
 | |
|             if (!$newCol->equals($curCol)) {
 | |
|                 $tomod[] = $newCol->name;
 | |
|             }
 | |
|         }
 | |
| 
 | |
|         if (count($toadd) + count($todrop) + count($tomod) == 0) {
 | |
|             // nothing to do
 | |
|             return true;
 | |
|         }
 | |
| 
 | |
|         // For efficiency, we want this all in one
 | |
|         // query, instead of using our methods.
 | |
| 
 | |
|         $phrase = array();
 | |
| 
 | |
|         foreach ($toadd as $columnName) {
 | |
|             $cd = $this->_byName($columns, $columnName);
 | |
| 
 | |
|             $phrase[] = 'ADD COLUMN ' . $this->_columnSql($cd);
 | |
|         }
 | |
| 
 | |
|         foreach ($todrop as $columnName) {
 | |
|             $phrase[] = 'DROP COLUMN ' . $columnName;
 | |
|         }
 | |
| 
 | |
|         foreach ($tomod as $columnName) {
 | |
|             $cd = $this->_byName($columns, $columnName);
 | |
| 
 | |
|             $phrase[] = 'MODIFY COLUMN ' . $this->_columnSql($cd);
 | |
|         }
 | |
| 
 | |
|         $sql = 'ALTER TABLE ' . $tableName . ' ' . implode(', ', $phrase);
 | |
| 
 | |
|         $res = $this->conn->query($sql);
 | |
| 
 | |
|         if (PEAR::isError($res)) {
 | |
|             throw new Exception($res->getMessage());
 | |
|         }
 | |
| 
 | |
|         return true;
 | |
|     }
 | |
| 
 | |
|     /**
 | |
|      * Returns the array of names from an array of
 | |
|      * ColumnDef objects.
 | |
|      *
 | |
|      * @param array $cds array of ColumnDef objects
 | |
|      *
 | |
|      * @return array strings for name values
 | |
|      */
 | |
| 
 | |
|     private function _names($cds)
 | |
|     {
 | |
|         $names = array();
 | |
| 
 | |
|         foreach ($cds as $cd) {
 | |
|             $names[] = $cd->name;
 | |
|         }
 | |
| 
 | |
|         return $names;
 | |
|     }
 | |
| 
 | |
|     /**
 | |
|      * Get a ColumnDef from an array matching
 | |
|      * name.
 | |
|      *
 | |
|      * @param array  $cds  Array of ColumnDef objects
 | |
|      * @param string $name Name of the column
 | |
|      *
 | |
|      * @return ColumnDef matching item or null if no match.
 | |
|      */
 | |
| 
 | |
|     private function _byName($cds, $name)
 | |
|     {
 | |
|         foreach ($cds as $cd) {
 | |
|             if ($cd->name == $name) {
 | |
|                 return $cd;
 | |
|             }
 | |
|         }
 | |
| 
 | |
|         return null;
 | |
|     }
 | |
| 
 | |
|     /**
 | |
|      * Return the proper SQL for creating or
 | |
|      * altering a column.
 | |
|      *
 | |
|      * Appropriate for use in CREATE TABLE or
 | |
|      * ALTER TABLE statements.
 | |
|      *
 | |
|      * @param ColumnDef $cd column to create
 | |
|      *
 | |
|      * @return string correct SQL for that column
 | |
|      */
 | |
| 
 | |
|     private function _columnSql($cd)
 | |
|     {
 | |
|         $sql = "{$cd->name} ";
 | |
| 
 | |
|         if (!empty($cd->size)) {
 | |
|             $sql .= "{$cd->type}({$cd->size}) ";
 | |
|         } else {
 | |
|             $sql .= "{$cd->type} ";
 | |
|         }
 | |
| 
 | |
|         if (!empty($cd->default)) {
 | |
|             $sql .= "default {$cd->default} ";
 | |
|         } else {
 | |
|             $sql .= ($cd->nullable) ? "null " : "not null ";
 | |
|         }
 | |
| 
 | |
|         if (!empty($cd->auto_increment)) {
 | |
|             $sql .= " auto_increment ";
 | |
|         }
 | |
| 
 | |
|         if (!empty($cd->extra)) {
 | |
|             $sql .= "{$cd->extra} ";
 | |
|         }
 | |
| 
 | |
|         return $sql;
 | |
|     }
 | |
| }
 | |
| 
 | |
| class SchemaTableMissingException extends Exception
 | |
| {
 | |
|     // no-op
 | |
| }
 | |
| 
 |