gnu-social/classes/Managed_DataObject.php
2015-02-18 12:15:46 +01:00

400 lines
13 KiB
PHP

<?php
/*
* StatusNet - the distributed open-source microblogging tool
* Copyright (C) 2010, StatusNet, Inc.
*
* 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/>.
*/
/**
* Wrapper for Memcached_DataObject which knows its own schema definition.
* Builds its own damn settings from a schema definition.
*
* @author Brion Vibber <brion@status.net>
*/
abstract class Managed_DataObject extends Memcached_DataObject
{
/**
* The One True Thingy that must be defined and declared.
*/
public static function schemaDef()
{
throw new MethodNotImplementedException(__METHOD__);
}
/**
* Get an instance by key
*
* @param string $k Key to use to lookup (usually 'id' for this class)
* @param mixed $v Value to lookup
*
* @return get_called_class() object if found, or null for no hits
*
*/
static function getKV($k,$v=NULL)
{
return parent::getClassKV(get_called_class(), $k, $v);
}
/**
* Get an instance by compound key
*
* This is a utility method to get a single instance with a given set of
* key-value pairs. Usually used for the primary key for a compound key; thus
* the name.
*
* @param array $kv array of key-value mappings
*
* @return get_called_class() object if found, or null for no hits
*
*/
static function pkeyGet(array $kv)
{
return parent::pkeyGetClass(get_called_class(), $kv);
}
/**
* Get multiple items from the database by key
*
* @param string $keyCol name of column for key
* @param array $keyVals key values to fetch
* @param boolean $skipNulls return only non-null results?
*
* @return array Array of objects, in order
*/
static function multiGet($keyCol, array $keyVals, $skipNulls=true)
{
return parent::multiGetClass(get_called_class(), $keyCol, $keyVals, $skipNulls);
}
/**
* Get multiple items from the database by key
*
* @param string $keyCol name of column for key
* @param array $keyVals key values to fetch
* @param array $otherCols Other columns to hold fixed
*
* @return array Array mapping $keyVals to objects, or null if not found
*/
static function pivotGet($keyCol, array $keyVals, array $otherCols=array())
{
return parent::pivotGetClass(get_called_class(), $keyCol, $keyVals, $otherCols);
}
/**
* Get a multi-instance object
*
* This is a utility method to get multiple instances with a given set of
* values for a specific column.
*
* @param string $keyCol key column name
* @param array $keyVals array of key values
*
* @return get_called_class() object with multiple instances if found,
* Exception is thrown when no entries are found.
*
*/
static function listFind($keyCol, array $keyVals)
{
return parent::listFindClass(get_called_class(), $keyCol, $keyVals);
}
/**
* Get a multi-instance object separated into an array
*
* This is a utility method to get multiple instances with a given set of
* values for a specific key column. Usually used for the primary key when
* multiple values are desired. Result is an array.
*
* @param string $keyCol key column name
* @param array $keyVals array of key values
*
* @return array with an get_called_class() object for each $keyVals entry
*
*/
static function listGet($keyCol, array $keyVals)
{
return parent::listGetClass(get_called_class(), $keyCol, $keyVals);
}
/**
* get/set an associative array of table columns
*
* @access public
* @return array (associative)
*/
public function table()
{
$table = static::schemaDef();
return array_map(array($this, 'columnBitmap'), $table['fields']);
}
/**
* get/set an array of table primary keys
*
* Key info is pulled from the table definition array.
*
* @access private
* @return array
*/
function keys()
{
return array_keys($this->keyTypes());
}
/**
* Get a sequence key
*
* Returns the first serial column defined in the table, if any.
*
* @access private
* @return array (column,use_native,sequence_name)
*/
function sequenceKey()
{
$table = static::schemaDef();
foreach ($table['fields'] as $name => $column) {
if ($column['type'] == 'serial') {
// We have a serial/autoincrement column.
// Declare it to be a native sequence!
return array($name, true, false);
}
}
// No sequence key on this table.
return array(false, false, false);
}
/**
* Return key definitions for DB_DataObject and Memcache_DataObject.
*
* DB_DataObject needs to know about keys that the table has; this function
* defines them.
*
* @return array key definitions
*/
function keyTypes()
{
$table = static::schemaDef();
$keys = array();
if (!empty($table['unique keys'])) {
foreach ($table['unique keys'] as $idx => $fields) {
foreach ($fields as $name) {
$keys[$name] = 'U';
}
}
}
if (!empty($table['primary key'])) {
foreach ($table['primary key'] as $name) {
$keys[$name] = 'K';
}
}
return $keys;
}
/**
* Build the appropriate DB_DataObject bitfield map for this field.
*
* @param array $column
* @return int
*/
function columnBitmap($column)
{
$type = $column['type'];
// For quoting style...
$intTypes = array('int',
'integer',
'float',
'serial',
'numeric');
if (in_array($type, $intTypes)) {
$style = DB_DATAOBJECT_INT;
} else {
$style = DB_DATAOBJECT_STR;
}
// Data type formatting style...
$formatStyles = array('blob' => DB_DATAOBJECT_BLOB,
'text' => DB_DATAOBJECT_TXT,
'date' => DB_DATAOBJECT_DATE,
'time' => DB_DATAOBJECT_TIME,
'datetime' => DB_DATAOBJECT_DATE | DB_DATAOBJECT_TIME,
'timestamp' => DB_DATAOBJECT_MYSQLTIMESTAMP);
if (isset($formatStyles[$type])) {
$style |= $formatStyles[$type];
}
// Nullable?
if (!empty($column['not null'])) {
$style |= DB_DATAOBJECT_NOTNULL;
}
return $style;
}
function links()
{
$links = array();
$table = static::schemaDef();
foreach ($table['foreign keys'] as $keyname => $keydef) {
if (count($keydef) == 2 && is_string($keydef[0]) && is_array($keydef[1]) && count($keydef[1]) == 1) {
if (isset($keydef[1][0])) {
$links[$keydef[1][0]] = $keydef[0].':'.$keydef[1][1];
}
}
}
return $links;
}
/**
* Return a list of all primary/unique keys / vals that will be used for
* caching. This will understand compound unique keys, which
* Memcached_DataObject doesn't have enough info to handle properly.
*
* @return array of strings
*/
function _allCacheKeys()
{
$table = static::schemaDef();
$ckeys = array();
if (!empty($table['unique keys'])) {
$keyNames = $table['unique keys'];
foreach ($keyNames as $idx => $fields) {
$val = array();
foreach ($fields as $name) {
$val[$name] = self::valueString($this->$name);
}
$ckeys[] = self::multicacheKey($this->tableName(), $val);
}
}
if (!empty($table['primary key'])) {
$fields = $table['primary key'];
$val = array();
foreach ($fields as $name) {
$val[$name] = self::valueString($this->$name);
}
$ckeys[] = self::multicacheKey($this->tableName(), $val);
}
return $ckeys;
}
public function escapedTableName()
{
return common_database_tablename($this->tableName());
}
/**
* Returns an ID, checked that it is set and reasonably valid
*
* If this dataobject uses a special id field (not 'id'), just
* implement your ID getting method in the child class.
*
* @return int ID of dataobject
* @throws Exception (when ID is not available or not set yet)
*/
public function getID()
{
// FIXME: Make these exceptions more specific (their own classes)
if (!isset($this->id)) {
throw new Exception('No ID set.');
} elseif (empty($this->id)) {
throw new Exception('Empty ID for object! (not inserted yet?).');
}
// FIXME: How about forcing to return an int? Or will that overflow eventually?
return $this->id;
}
// 'update' won't write key columns, so we have to do it ourselves.
// This also automatically calls "update" _before_ it sets the keys.
// FIXME: This only works with single-column primary keys so far! Beware!
/**
* @param DB_DataObject &$orig Must be "instanceof" $this
* @param string $pid Primary ID column (no escaping is done on column name!)
*/
public function updateWithKeys(&$orig, $pid='id')
{
if (!$orig instanceof $this) {
throw new ServerException('Tried updating a DataObject with a different class than itself.');
}
// do it in a transaction
$this->query('BEGIN');
$parts = array();
foreach ($this->keys() as $k) {
if (strcmp($this->$k, $orig->$k) != 0) {
$parts[] = $k . ' = ' . $this->_quote($this->$k);
}
}
if (count($parts) == 0) {
// No changes to keys, it's safe to run ->update(...)
if ($this->update($orig) === false) {
common_log_db_error($this, 'UPDATE', __FILE__);
// rollback as something bad occurred
$this->query('ROLLBACK');
throw new ServerException("Could not UPDATE non-keys for {$this->__table}");
}
$orig->decache();
$this->encache();
// commit our db transaction since we won't reach the COMMIT below
$this->query('COMMIT');
// @FIXME return true only if something changed (otherwise 0)
return true;
}
$qry = sprintf('UPDATE %1$s SET %2$s WHERE %3$s = %4$s',
common_database_tablename($this->tableName()),
implode(', ', $parts),
$pid,
$this->_quote($this->$pid));
$result = $this->query($qry);
if ($result === false) {
common_log_db_error($this, 'UPDATE', __FILE__);
// rollback as something bad occurred
$this->query('ROLLBACK');
throw new ServerException("Could not UPDATE key fields for {$this->__table}");
}
// Update non-keys too, if the previous endeavour worked.
// The ->update call uses "$this" values for keys, that's why we can't do this until
// the keys are updated (because they might differ from $orig and update the wrong entries).
if ($this->update($orig) === false) {
common_log_db_error($this, 'UPDATE', __FILE__);
// rollback as something bad occurred
$this->query('ROLLBACK');
throw new ServerException("Could not UPDATE non-keys for {$this->__table}");
}
$orig->decache();
$this->encache();
// commit our db transaction
$this->query('COMMIT');
// @FIXME return true only if something changed (otherwise 0)
return $result;
}
}