X-Git-Url: https://git.mxchange.org/?a=blobdiff_plain;ds=sidebyside;f=lib%2Fschema.php;h=e5def514e31ddbc227ecb2a6afaec272c9c5d2dc;hb=3c28464daba8cbb2d8362c38ebb8e2c41ff5049f;hp=db2f49a789ec637bb9c020851845636ebfa31d46;hpb=4f833531dd5aa05e56ab00dd95eda4ce8419564d;p=quix0rs-gnu-social.git

diff --git a/lib/schema.php b/lib/schema.php
index db2f49a789..e5def514e3 100644
--- a/lib/schema.php
+++ b/lib/schema.php
@@ -1,6 +1,6 @@
 <?php
 /**
- * Laconica, the distributed open-source microblogging tool
+ * StatusNet, the distributed open-source microblogging tool
  *
  * Database schema utilities
  *
@@ -20,14 +20,14 @@
  * 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.
+ * @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://laconi.ca/
+ * @link      http://status.net/
  */
 
-if (!defined('LACONICA')) {
+if (!defined('STATUSNET')) {
     exit(1);
 }
 
@@ -39,86 +39,462 @@ if (!defined('LACONICA')) {
  * utilities.
  *
  * @category Database
- * @package  Laconica
- * @author   Evan Prodromou <evan@controlyourself.ca>
+ * @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://laconi.ca/
+ * @link     http://status.net/
  */
 
 class Schema
 {
-    protected $db = null;
+    static $_static = null;
+    protected $conn = null;
 
-    static function get()
+    /**
+     * 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;
     }
 
-    public function getTableDef($name)
+    /**
+     * Main public entry point. Use this to get
+     * the schema object.
+     *
+     * @return Schema the Schema object for the connection
+     */
+
+    static function get($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);
 
-    public function getIndexDef($table, $index)
-    {
+        foreach ($td->columns as $cd) {
+            if ($cd->name == $column) {
+                return $cd;
+            }
+        }
+
+        return null;
     }
 
-    public function createTable($name, $columns, $indices=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;
     }
 
-    public function createIndex($name, $table, $columns)
+    /**
+     * 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;
     }
 
-    public function dropIndex($name, $table)
+    /**
+     * 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;
     }
 
-    public function modifyColumn($table, $column, $columndef)
+    /**
+     * 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;
     }
 
-    public function dropColumn($table, $column)
+    /**
+     * 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;
     }
 
-    public function ensureTable($name, $columns, $indices)
+    /**
+     * 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)
     {
-        $def = $this->tableDef($name);
-        if (empty($def)) {
-            return $this->createTable($name, $columns, $indices);
+        // 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;
     }
-}
 
-class TableDef
-{
-    public $name;
-    public $columns;
-}
+    /**
+     * Returns the array of names from an array of
+     * ColumnDef objects.
+     *
+     * @param array $cds array of ColumnDef objects
+     *
+     * @return array strings for name values
+     */
 
-class ColumnDef
-{
-    public $name;
-    public $type;
-    public $size;
+    private function _names($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 IndexDef
+class SchemaTableMissingException extends Exception
 {
-    public $name;
-    public $table;
-    public $columns;
+    // no-op
 }
+