--- /dev/null
+<?php
+/***************************************************************************
+ * Copyright (C) 2003-2010 Polytechnique.org *
+ * http://opensource.polytechnique.org/ *
+ * *
+ * This program is free software; you can redistribute it and/or modify *
+ * it under the terms of the GNU General Public License as published by *
+ * the Free Software Foundation; either version 2 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 General Public License for more details. *
+ * *
+ * You should have received a copy of the GNU General Public License *
+ * along with this program; if not, write to the Free Software *
+ * Foundation, Inc., *
+ * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA *
+ ***************************************************************************/
+
+class PlDBBadValueException extends PlException
+{
+ public function __construct($value, PlDBTableField $field, $reason)
+ {
+ parent::__construct('Erreur lors de l\'accès à la base de données',
+ 'Illegal value '. (is_null($value) ? '(null)' : '(\'' . $value . '\')')
+ . ' for field (\'' . $field->table->table . '.' . $field->name . '\'): '
+ . $reason);
+ }
+}
+
+class PlDBNoSuchFieldException extends PlException
+{
+ public function __construct($field, PlDBTable $table)
+ {
+ parent::__construct('Erreur lors de l\'accès à la base de données',
+ 'No such field ' . $field . ' in table ' . $table->table);
+ }
+}
+
+class PlDBIncompleteEntryDescription extends PlException
+{
+ public function __construct($field, PlDBTable $table)
+ {
+ parent::__construct('Erreur lors de l\'accès à la base de données',
+ 'The field ' . $field . ' is required to describe an entry in table '
+ . $table->table);
+ }
+}
+
+class PlDBTableField
+{
+ public $table;
+
+ public $name;
+ public $inPrimaryKey;
+ public $inUniqueKey;
+ public $inKey;
+
+ public $type;
+ public $typeLength;
+ public $typeParameters;
+
+ public $allowNull;
+ public $defaultValue;
+ public $autoIncrement;
+
+ public function __construct(array $column)
+ {
+ $this->name = $column['Field'];
+ $this->typeParameters = explode(' ', str_replace(array('(', ')', ',', '\''), ' ',
+ $column['Type']));
+ $this->type = array_shift($this->typeParameters);
+ if ($this->type == 'enum' || $this->type == 'set') {
+ $this->typeParameters = new PlFlagSet(implode(',', $this->typeParameters));
+ } else if (ctype_digit($this->typeParameters[0])) {
+ $this->typeLength = intval($this->typeParameters[0]);
+ array_shift($this->typeParameters);
+ }
+ $this->allowNull = ($column['Null'] === 'YES');
+ $this->autoIncrement = (strpos($column['Extra'], 'auto_increment') !== false);
+ $this->inPrimaryKey = ($column['Key'] === 'PRI');
+ $this->inUniqueKey = $this->inPrimaryKey || ($column['Key'] === 'UNI');
+ $this->inKey = $this->inUniqueKey || ($column['Key'] === 'MUL');
+
+ try {
+ $this->defaultValue = $this->format($column['Default']);
+ } catch (PlDBBadValueException $e) {
+ $this->defaultValue = null;
+ }
+ }
+
+ public function format($value, $badNullFallbackToDefault = false)
+ {
+ if (is_null($value)) {
+ if ($this->allowNull || $this->autoIncrement) {
+ return $value;
+ }
+ if ($badNullFallbackToDefault) {
+ return $this->defaultValue;
+ }
+ throw new PlDBBadValueException($value, $this, 'null not allowed');
+ } else if ($this->type == 'enum') {
+ if (!$this->typeParameters->hasFlag($value)) {
+ throw new PlDBBadValueException($value, $this, 'invalid value for enum ' . $this->typeParameters->flags());
+ }
+ return $value;
+ } else if ($this->type == 'set') {
+ $value = new PlFlagSet($value);
+ foreach ($value as $flag) {
+ if (!$this->typeParameters->hasFlag($flag)) {
+ throw new PlDBBadValueException($value, $this, 'invalid flag for set ' . $this->typeParameters->flags());
+ }
+ }
+ return $value;
+ } else if (ends_with($this->type, 'int')) {
+ if (!is_int($value) && !ctype_digit($value)) {
+ throw new PlDBBadValueException($value, $this, 'value is not an integer');
+ }
+ $value = intval($value);
+ if (count($this->typeParameters) > 0 && $this->typeParameters[0] == 'unsigned') {
+ if ($value < 0) {
+ throw new PlDBBadValueException($value, $this, 'value is negative in an unsigned field');
+ }
+ }
+ /* TODO: Check bounds */
+ return $value;
+ } else if ($this->type == 'varchar') {
+ if (strlen($value) > $this->typeLength) {
+ throw new PlDBBadValueException($value, $this, 'value is expected to be at most ' . $this->typeLength . ' characters long, ' . strlen($value) . ' given');
+ }
+ return $value;
+ } else if ($this->type == 'char') {
+ if (strlen($value) != $this->typeLength) {
+ throw new PlDBBadValueException($value, $this, 'value is expected to be ' . $this->typeLength . ' characters long, ' . strlen($value) . ' given');
+ }
+ return $value;
+ }
+ /* TODO: Support data and times */
+ return $value;
+ }
+}
+
+
+/** This class aims at providing a simple interface to interact with a single
+ * table of a database. It is implemented as a wrapper around XDB.
+ */
+class PlDBTable
+{
+ public $table;
+
+ private $schema;
+ private $keyFields;
+ private $mutableFields;
+
+ public function __construct($table)
+ {
+ $this->table = $table;
+ $this->schema();
+ }
+
+ private function parseSchema(PlIterator $schema)
+ {
+ $this->schema = array();
+ $this->keyFields = array();
+ $this->mutableFields = array();
+ while ($column = $schema->next()) {
+ $field = new PlDBTableField($column);
+ $this->schema[$field->name] = $field;
+ if ($field->inPrimaryKey) {
+ $this->keyFields[] = $field->name;
+ } else {
+ $this->mutableFields[] = $field->name;
+ }
+ }
+ }
+
+
+ private function schema()
+ {
+ if (!$this->schema) {
+ $schema = XDB::iterator('DESCRIBE ' . $this->table);
+ $this->parseSchema($schema);
+ }
+ return $this->schema;
+ }
+
+ private function field($field)
+ {
+ $schema = $this->schema();
+ if (!isset($schema[$field])) {
+ throw new PlDBNoSuchFieldException($field, $this);
+ }
+ return $schema[$field];
+ }
+
+ public function formatField($field, $value)
+ {
+ return $this->field($field)->format($value);
+ }
+
+ public function defaultValue($field)
+ {
+ return $this->field($field)->defaultValue;
+ }
+
+ public function primaryKey(PlDBTableEntry $entry)
+ {
+ $key = array();
+ foreach ($this->keyFields as $field) {
+ if (!isset($entry->$field)) {
+ throw new PlDBIncompleteEntryDescription($field, $this);
+ } else {
+ $key[] = XDB::escape($this->$field);
+ }
+ }
+ return implode('-', $key);
+ }
+
+ private function buildKeyCondition(PlDBTableEntry $entry, $allowIncomplete)
+ {
+ $condition = array();
+ foreach ($this->keyFields as $field) {
+ if (!isset($entry->$field)) {
+ if (!$allowIncomplete) {
+ throw new PlDBIncompleteEntryDescription($field, $this);
+ }
+ } else {
+ $condition[] = XDB::format($field . ' = {?}', $entry->$field);
+ }
+ }
+ return implode(' AND ', $condition);
+ }
+
+ public function fetchEntry(PlDBTableEntry $entry)
+ {
+ $result = XDB::rawFetchOneAssoc('SELECT *
+ FROM ' . $this->table . '
+ WHERE ' . $this->buildKeyCondition($entry, false));
+ if (!$result) {
+ return false;
+ }
+ return $entry->fillFromDBData($result);
+ }
+
+ public function iterateOnEntry(PlDBTableEntry $entry)
+ {
+ $it = XDB::rawIterator('SELECT *
+ FROM ' . $this->table . '
+ WHERE ' . $this->buildKeyCondition($entry, true));
+ return PlIteratorUtils::map($it, array($entry, 'cloneAndFillFromDBData'));
+ }
+
+ public function updateEntry(PlDBTableEntry $entry)
+ {
+ $values = array();
+ foreach ($this->mutableFields as $field) {
+ if ($entry->hasChanged($field)) {
+ $values[] = XDB::format($field . ' = {?}', $entry->$field);
+ }
+ }
+ if (count($values) > 0) {
+ XDB::rawExecute('UPDATE ' . $this->table . '
+ SET ' . implode(', ', $values) . '
+ WHERE ' . $this->buildKeyCondition($entry, false));
+ }
+ }
+
+ public static function get($name)
+ {
+ var_dump('blah');
+ return new PlDBTable($name);
+ }
+}
+
+class PlDBTableEntry extends PlAbstractIterable
+{
+ private $table;
+ private $changed;
+ private $fetched = false;
+ private $autoFetch;
+
+ private $data = array();
+
+ public function __construct($table, $autoFetch = false)
+ {
+ if ($table instanceof PlDBTable) {
+ $this->table = $table;
+ } else {
+ $this->table = PlCache::getGlobal('pldbtable_' . $table, array('PlDBTable', 'get'), array($table));
+ }
+ $this->autoFetch = $autoFetch;
+ $this->changed = new PlFlagSet();
+ }
+
+ /** This hook is called when the entry is going to be updated in the db.
+ *
+ * A typical usecase is a class that stores low-level representation of
+ * an object in db and perform a conversion between this low-level representation
+ * and a higher-level representation.
+ *
+ * @return true in case of success
+ */
+ protected function preSave()
+ {
+ return true;
+ }
+
+ /** This hook is called when the entry has just been fetched from the db.
+ *
+ * This is the counterpart of @ref preSave and a typical use-case is the conversion
+ * from a high-level representation of the objet to a representation suitable for
+ * storage in the database.
+ *
+ * @return true in case of success.
+ */
+ protected function postFetch()
+ {
+ return true;
+ }
+
+ public function __get($field)
+ {
+ if (isset($this->data[$field])) {
+ return $this->data[$field];
+ } else if (!$this->fetched && $this->autoFetch) {
+ $this->fetch();
+ if (isset($this->data[$field])) {
+ return $this->data[$field];
+ }
+ }
+ return $this->table->defaultValue($field);
+ }
+
+ public function __set($field, $value)
+ {
+ $this->data[$field] = $this->table->formatField($field, $value);
+ $this->changed->addFlag($field);
+ }
+
+ public function __isset($field)
+ {
+ return isset($this->data[$field]);
+ }
+
+ public function primaryKey()
+ {
+ $this->table->primaryKey($this);
+ }
+
+ public function hasChanged($field)
+ {
+ return $this->changed->hasFlag($field);
+ }
+
+ public function fillFromArray(array $data)
+ {
+ foreach ($data as $field => $value) {
+ $this->$field = $value;
+ }
+ }
+
+ public function fillFromDBData(array $data)
+ {
+ $this->fillFromArray($data);
+ $this->changed->clear();
+ return $this->postFetch();
+ }
+
+ public function cloneAndFillFromDBData(array $data)
+ {
+ $clone = clone $this;
+ $clone->fillFromDBData($data);
+ return $clone;
+ }
+
+ public function fetch()
+ {
+ return $this->table->fetchEntry($this);
+ }
+
+ public function iterate()
+ {
+ return $this->table->iterateOnEntry($this);
+ }
+
+ public function save()
+ {
+ if (!$this->preSave()) {
+ return false;
+ }
+ $this->table->updateEntry($this);
+ $this->changed->clear();
+ return true;
+ }
+}
+
+// vim:set et sw=4 sts=4 sws=4 foldmethod=marker enc=utf-8:
+?>
projects / platal.git / commitdiff