class Schema
{
- static $_single = null;
+ static $_static = null;
protected $conn = null;
- protected function __construct()
- {
- // XXX: there should be an easier way to do this.
- $user = new User();
- $this->conn = $user->getDatabaseConnection();
- $user->free();
- unset($user);
- }
+ /**
+ * Constructor. Only run once for singleton object.
+ */
- static function get()
+ protected function __construct($conn = null)
{
- if (empty(self::$_single)) {
- self::$_single = new Schema();
+ if (is_null($conn)) {
+ // XXX: there should be an easier way to do this.
+ $user = new User();
+ $conn = $user->getDatabaseConnection();
+ $user->free();
+ unset($user);
}
- return self::$_single;
+
+ $this->conn = $conn;
}
- public function getTableDef($name)
- {
- $res =& $this->conn->query('DESCRIBE ' . $name);
+ /**
+ * Main public entry point. Use this to get
+ * the schema object.
+ *
+ * @return Schema the Schema object for the connection
+ */
- if (PEAR::isError($res)) {
- throw new Exception($res->getMessage());
+ static function get($conn = null)
+ {
+ if (is_null($conn)) {
+ $key = 'default';
+ } else {
+ $key = md5(serialize($conn->dsn));
}
-
- $td = new TableDef();
-
- $td->name = $name;
- $td->columns = array();
-
- $row = array();
-
- while ($res->fetchInto($row, DB_FETCHMODE_ASSOC)) {
-
- $cd = new ColumnDef();
-
- $cd->name = $row['Field'];
-
- $packed = $row['Type'];
-
- if (preg_match('/^(\w+)\((\d+)\)$/', $packed, $match)) {
- $cd->type = $match[1];
- $cd->size = $match[2];
- } else {
- $cd->type = $packed;
- }
-
- $cd->nullable = ($row['Null'] == 'YES') ? true : false;
- $cd->key = $row['Key'];
- $cd->default = $row['Default'];
- $cd->extra = $row['Extra'];
-
- $td->columns[] = $cd;
+
+ $type = common_config('db', 'type');
+ if (empty(self::$_static[$key])) {
+ $schemaClass = ucfirst($type).'Schema';
+ self::$_static[$key] = new $schemaClass($conn);
}
-
- return $td;
+ return self::$_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);
return null;
}
- public function getIndexDef($table, $index)
- {
- return null;
- }
-
- public function createTable($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();
$sql .= $this->_columnSql($cd);
switch ($cd->key) {
- case 'UNI':
+ case 'UNI':
$uniques[] = $cd->name;
break;
- case 'PRI':
+ case 'PRI':
$primary[] = $cd->name;
break;
- case 'MUL':
+ case 'MUL':
$indices[] = $cd->name;
break;
}
$sql .= "); ";
- common_debug($sql);
-
- $res =& $this->conn->query($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");
+ $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;
+ }
+
+ /**
+ * 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 $names;
}
- public function ensureTable($name, $columns, $indices)
+ /**
+ * 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)
{
- $def = $this->tableDef($name);
- if (empty($def)) {
- return $this->createTable($name, $columns, $indices);
+ foreach ($cds as $cd) {
+ if ($cd->name == $name) {
+ return $cd;
+ }
}
+
+ return null;
}
- function _columnSql($cd)
+ /**
+ * 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} ";
$sql .= ($cd->nullable) ? "null " : "not null ";
}
- return $sql;
- }
-}
+ if (!empty($cd->auto_increment)) {
+ $sql .= " auto_increment ";
+ }
-class TableDef
-{
- public $name;
- public $columns;
-}
+ if (!empty($cd->extra)) {
+ $sql .= "{$cd->extra} ";
+ }
-class ColumnDef
-{
- public $name;
- public $type;
- public $size;
- public $nullable;
- public $key;
- public $default;
- public $extra;
-
- function __construct($name, $type, $size=null, $nullable=null,
- $key=null, $default=null, $extra=null) {
- $this->name = $name;
- $this->type = $type;
- $this->size = $size;
- $this->nullable = $nullable;
- $this->key = $key;
- $this->default = $default;
- $this->extra = $extra;
+ return $sql;
}
}
-class IndexDef
+class SchemaTableMissingException extends Exception
{
- public $name;
- public $table;
- public $columns;
+ // no-op
}
+
projects / quix0rs-gnu-social.git / blobdiff