API: Refactor continuation code and add to purge, watch, etc.
[lhc/web/wiklou.git] / includes / api / ApiResult.php
index 7d0a15a..b30d9dd 100644 (file)
@@ -60,6 +60,13 @@ class ApiResult extends ApiBase {
 
        private $mData, $mIsRawMode, $mSize, $mCheckingSize;
 
+       private $continueAllModules = array();
+       private $continueGeneratedModules = array();
+       private $continuationData = array();
+       private $generatorContinuationData = array();
+       private $generatorParams = array();
+       private $generatorDone = false;
+
        /**
         * @param ApiMain $main
         */
@@ -437,4 +444,181 @@ class ApiResult extends ApiBase {
        public function execute() {
                ApiBase::dieDebug( __METHOD__, 'execute() is not supported on Result object' );
        }
+
+       /**
+        * Parse a 'continue' parameter and return status information.
+        *
+        * This must be balanced by a call to endContinuation().
+        *
+        * @since 1.24
+        * @param string|null $continue The "continue" parameter, if any
+        * @param array $allModules Contains ApiBase instances that will be executed
+        * @param array $generatedModules Names of modules that depend on the generator
+        * @return array Two elements: a boolean indicating if the generator is done,
+        *   and an array of modules to actually execute.
+        */
+       public function beginContinuation(
+               $continue, array $allModules = array(), array $generatedModules = array()
+       ) {
+               $this->continueGeneratedModules = $generatedModules
+                       ? array_combine( $generatedModules, $generatedModules )
+                       : array();
+               $this->continuationData = array();
+               $this->generatorContinuationData = array();
+               $this->generatorParams = array();
+
+               $skip = array();
+               if ( is_string( $continue ) && $continue !== '' ) {
+                       $continue = explode( '||', $continue );
+                       $this->dieContinueUsageIf( count( $continue ) !== 2 );
+                       $this->generatorDone = ( $continue[0] === '-' );
+                       if ( !$this->generatorDone ) {
+                               $this->generatorParams = explode( '|', $continue[0] );
+                       }
+                       $skip = explode( '|', $continue[1] );
+               }
+
+               $this->continueAllModules = array();
+               $runModules = array();
+               foreach ( $allModules as $module ) {
+                       $name = $module->getModuleName();
+                       if ( in_array( $name, $skip ) ) {
+                               $this->continueAllModules[$name] = false;
+                               // Prevent spurious "unused parameter" warnings
+                               $module->extractRequestParams();
+                       } else {
+                               $this->continueAllModules[$name] = true;
+                               $runModules[] = $module;
+                       }
+               }
+
+               return array(
+                       $this->generatorDone,
+                       $runModules,
+               );
+       }
+
+       /**
+        * Set the continuation parameter for a module
+        *
+        * @since 1.24
+        * @param ApiBase $module
+        * @param string $paramName
+        * @param string|array $paramValue
+        */
+       public function setContinueParam( ApiBase $module, $paramName, $paramValue ) {
+               $name = $module->getModuleName();
+               if ( !isset( $this->continueAllModules[$name] ) ) {
+                       throw new MWException(
+                               "Module '$name' called ApiResult::setContinueParam but was not " .
+                               'passed to ApiResult::beginContinuation'
+                       );
+               }
+               if ( !$this->continueAllModules[$name] ) {
+                       throw new MWException(
+                               "Module '$name' was not supposed to have been executed, but " .
+                               'it was executed anyway'
+                       );
+               }
+               $paramName = $module->encodeParamName( $paramName );
+               if ( is_array( $paramValue ) ) {
+                       $paramValue = join( '|', $paramValue );
+               }
+               $this->continuationData[$name][$paramName] = $paramValue;
+       }
+
+       /**
+        * Set the continuation parameter for the generator module
+        *
+        * @since 1.24
+        * @param ApiBase $module
+        * @param string $paramName
+        * @param string|array $paramValue
+        */
+       public function setGeneratorContinueParam( ApiBase $module, $paramName, $paramValue ) {
+               $name = $module->getModuleName();
+               $paramName = $module->encodeParamName( $paramName );
+               if ( is_array( $paramValue ) ) {
+                       $paramValue = join( '|', $paramValue );
+               }
+               $this->generatorContinuationData[$name][$paramName] = $paramValue;
+       }
+
+       /**
+        * Close continuation, writing the data into the result
+        *
+        * @since 1.24
+        * @param string $style 'standard' for the new style since 1.21, 'raw' for
+        *   the style used in 1.20 and earlier.
+        */
+       public function endContinuation( $style = 'standard' ) {
+               if ( $style === 'raw' ) {
+                       $key = 'query-continue';
+                       $data = array_merge_recursive(
+                               $this->continuationData, $this->generatorContinuationData
+                       );
+               } else {
+                       $key = 'continue';
+                       $data = array();
+
+                       $finishedModules = array_diff(
+                               array_keys( $this->continueAllModules ),
+                               array_keys( $this->continuationData )
+                       );
+
+                       // First, grab the non-generator-using continuation data
+                       $continuationData = array_diff_key(
+                               $this->continuationData, $this->continueGeneratedModules
+                       );
+                       foreach ( $continuationData as $module => $kvp ) {
+                               $data += $kvp;
+                       }
+
+                       // Next, handle the generator-using continuation data
+                       $continuationData = array_intersect_key(
+                               $this->continuationData, $this->continueGeneratedModules
+                       );
+                       if ( $continuationData ) {
+                               // Some modules are unfinished: include those params, and copy
+                               // the generator params.
+                               foreach ( $continuationData as $module => $kvp ) {
+                                       $data += $kvp;
+                               }
+                               $data += array_intersect_key(
+                                       $this->getMain()->getRequest()->getValues(),
+                                       array_flip( $this->generatorParams )
+                               );
+                       } else if ( $this->generatorContinuationData ) {
+                               // All the generator-using modules are complete, but the
+                               // generator isn't. Continue the generator and restart the
+                               // generator-using modules
+                               $this->generatorParams = array();
+                               foreach ( $this->generatorContinuationData as $kvp ) {
+                                       $this->generatorParams = array_merge(
+                                               $this->generatorParams, array_keys( $kvp )
+                                       );
+                                       $data += $kvp;
+                               }
+                               $finishedModules = array_diff(
+                                       $finishedModules, $this->continueGeneratedModules
+                               );
+                       } else {
+                               // Generator and prop modules are all done. Mark it so.
+                               $this->generatorDone = true;
+                       }
+
+                       // Set 'continue' if any continuation data is set or if the generator
+                       // still needs to run
+                       if ( $data || !$this->generatorDone ) {
+                               $data['continue'] =
+                                       ( $this->generatorDone ? '-' : join( '|', $this->generatorParams ) ) .
+                                       '||' . join( '|', $finishedModules );
+                       }
+               }
+               if ( $data ) {
+                       $this->disableSizeCheck();
+                       $this->addValue( null, $key, $data, ApiResult::ADD_ON_TOP );
+                       $this->enableSizeCheck();
+               }
+       }
 }