includes/api/ApiQueryORM.php

   1 <?php
   2
   3 /**
   4  * Base query module for querying results from ORMTables.
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License along
  17  * with this program; if not, write to the Free Software Foundation, Inc.,
  18  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  19  * http://www.gnu.org/copyleft/gpl.html
  20  *
  21  * @since 1.21
  22  *
  23  * @file
  24  * @ingroup API
  25  *
  26  * @license GNU GPL v2+
  27  * @author Jeroen De Dauw < jeroendedauw@gmail.com >
  28  */
  29 abstract class ApiQueryORM extends ApiQueryBase {
  30
  31         /**
  32          * Returns an instance of the IORMTable table being queried.
  33          *
  34          * @since 1.21
  35          *
  36          * @return IORMTable
  37          */
  38         abstract protected function getTable();
  39
  40         /**
  41          * Returns the name of the individual rows.
  42          * For example: page, user, contest, campaign, etc.
  43          * This is used to appropriately name elements in XML.
  44          * Deriving classes typically override this method.
  45          *
  46          * @since 1.21
  47          *
  48          * @return string
  49          */
  50         protected function getRowName() {
  51                 return 'item';
  52         }
  53
  54         /**
  55          * Returns the name of the list of rows.
  56          * For example: pages, users, contests, campaigns, etc.
  57          * This is used to appropriately name nodes in the output.
  58          * Deriving classes typically override this method.
  59          *
  60          * @since 1.21
  61          *
  62          * @return string
  63          */
  64         protected function getListName() {
  65                 return 'items';
  66         }
  67
  68         /**
  69          * Returns the path to where the items results should be added in the result.
  70          *
  71          * @since 1.21
  72          *
  73          * @return null|string|array
  74          */
  75         protected function getResultPath() {
  76                 return null;
  77         }
  78
  79         /**
  80          * Get the parameters, find out what the conditions for the query are,
  81          * run it, and add the results.
  82          *
  83          * @since 1.21
  84          */
  85         public function execute() {
  86                 $params = $this->getParams();
  87
  88                 if ( !in_array( 'id', $params['props'] ) ) {
  89                         $params['props'][] = 'id';
  90                 }
  91
  92                 $results = $this->getResults( $params, $this->getConditions( $params ) );
  93                 $this->addResults( $params, $results );
  94         }
  95
  96         /**
  97          * Get the request parameters and remove all params set
  98          * to null (ie those that are not actually provided).
  99          *
 100          * @since 1.21
 101          *
 102          * @return array
 103          */
 104         protected function getParams() {
 105                 return array_filter(
 106                         $this->extractRequestParams(),
 107                         function( $prop ) {
 108                                 return isset( $prop );
 109                         }
 110                 );
 111         }
 112
 113         /**
 114          * Get the conditions for the query. These will be provided as
 115          * regular parameters, together with limit, props, continue,
 116          * and possibly others which we need to get rid off.
 117          *
 118          * @since 1.21
 119          *
 120          * @param array $params
 121          *
 122          * @return array
 123          */
 124         protected function getConditions( array $params ) {
 125                 $conditions = array();
 126                 $fields = $this->getTable()->getFields();
 127
 128                 foreach ( $params as $name => $value ) {
 129                         if ( array_key_exists( $name, $fields ) ) {
 130                                 $conditions[$name] = $value;
 131                         }
 132                 }
 133
 134                 return $conditions;
 135         }
 136
 137         /**
 138          * Get the actual results.
 139          *
 140          * @since 1.21
 141          *
 142          * @param array $params
 143          * @param array $conditions
 144          *
 145          * @return ORMResult
 146          */
 147         protected function getResults( array $params, array $conditions ) {
 148                 return $this->getTable()->select(
 149                         $params['props'],
 150                         $conditions,
 151                         array(
 152                                 'LIMIT' => $params['limit'] + 1,
 153                                 'ORDER BY' => $this->getTable()->getPrefixedField( 'id' ) . ' ASC',
 154                         ),
 155                         __METHOD__
 156                 );
 157         }
 158
 159         /**
 160          * Serialize the results and add them to the result object.
 161          *
 162          * @since 1.21
 163          *
 164          * @param array $params
 165          * @param ORMResult $results
 166          */
 167         protected function addResults( array $params, ORMResult $results ) {
 168                 $serializedResults = array();
 169                 $count = 0;
 170
 171                 foreach ( $results as /* IORMRow */ $result ) {
 172                         if ( ++$count > $params['limit'] ) {
 173                                 // We've reached the one extra which shows that
 174                                 // there are additional pages to be had. Stop here...
 175                                 $this->setContinueEnumParameter( 'continue', $result->getId() );
 176                                 break;
 177                         }
 178
 179                         $serializedResults[] = $this->formatRow( $result, $params );
 180                 }
 181
 182                 $this->setIndexedTagNames( $serializedResults );
 183                 $this->addSerializedResults( $serializedResults );
 184         }
 185
 186         /**
 187          * Formats a row to it's desired output format.
 188          *
 189          * @since 1.21
 190          *
 191          * @param IORMRow $result
 192          * @param array $params
 193          *
 194          * @return mixed
 195          */
 196         protected function formatRow( IORMRow $result, array $params ) {
 197                 return $result->toArray( $params['props'] );
 198         }
 199
 200         /**
 201          * Set the tag names for formats such as XML.
 202          *
 203          * @since 1.21
 204          *
 205          * @param array $serializedResults
 206          */
 207         protected function setIndexedTagNames( array &$serializedResults ) {
 208                 $this->getResult()->setIndexedTagName( $serializedResults, $this->getRowName() );
 209         }
 210
 211         /**
 212          * Add the serialized results to the result object.
 213          *
 214          * @since 1.21
 215          *
 216          * @param array $serializedResults
 217          */
 218         protected function addSerializedResults( array $serializedResults ) {
 219                 $this->getResult()->addValue(
 220                         $this->getResultPath(),
 221                         $this->getListName(),
 222                         $serializedResults
 223                 );
 224         }
 225
 226         /**
 227          * @see ApiBase::getAllowedParams()
 228          * @return array
 229          */
 230         public function getAllowedParams() {
 231                 $params = array(
 232                         'props' => array(
 233                                 ApiBase::PARAM_TYPE => $this->getTable()->getFieldNames(),
 234                                 ApiBase::PARAM_ISMULTI => true,
 235                                 ApiBase::PARAM_REQUIRED => true,
 236                         ),
 237                         'limit' => array(
 238                                 ApiBase::PARAM_DFLT => 20,
 239                                 ApiBase::PARAM_TYPE => 'limit',
 240                                 ApiBase::PARAM_MIN => 1,
 241                                 ApiBase::PARAM_MAX => ApiBase::LIMIT_BIG1,
 242                                 ApiBase::PARAM_MAX2 => ApiBase::LIMIT_BIG2
 243                         ),
 244                         'continue' => null,
 245                 );
 246
 247                 return array_merge( $this->getTable()->getAPIParams(), $params );
 248         }
 249
 250         /**
 251          * @see ApiBase::getParamDescription()
 252          * @return array
 253          */
 254         public function getParamDescription() {
 255                 $descriptions = array(
 256                         'props' => 'Fields to query',
 257                         'continue' => 'Offset number from where to continue the query',
 258                         'limit' => 'Max amount of rows to return',
 259                 );
 260
 261                 return array_merge( $this->getTable()->getFieldDescriptions(), $descriptions );
 262         }
 263
 264 }