Fix layer cache to work with layers which have the same id (but in di…

…fferent project files)

src/server/qgsmslayercache.cpp

@@ -16,6 +16,7 @@
  ***************************************************************************/
 
 #include "qgsmslayercache.h"
+#include "qgsmessagelog.h"
 #include "qgsvectorlayer.h"
 #include "qgslogger.h"
 #include <QFile>
@@ -55,18 +56,13 @@ QgsMSLayerCache::~QgsMSLayerCache()
 
 void QgsMSLayerCache::insertLayer( const QString& url, const QString& layerName, QgsMapLayer* layer, const QString& configFile, const QList<QString>& tempFiles )
 {
-  QgsDebugMsg( "inserting layer" );
+  QgsMessageLog::logMessage( "Layer cache: insert Layer '" + layerName + "' configFile: " + configFile, "Server", QgsMessageLog::INFO );
   if ( mEntries.size() > std::max( mDefaultMaxLayers, mProjectMaxLayers ) ) //force cache layer examination after 10 inserted layers
   {
     updateEntries();
   }
 
   QPair<QString, QString> urlLayerPair = qMakePair( url, layerName );
-  QHash<QPair<QString, QString>, QgsMSLayerCacheEntry>::iterator it = mEntries.find( urlLayerPair );
-  if ( it != mEntries.end() )
-  {
-    delete it.value().layerPointer;
-  }
 
   QgsMSLayerCacheEntry newEntry;
   newEntry.layerPointer = layer;
@@ -94,41 +90,55 @@ void QgsMSLayerCache::insertLayer( const QString& url, const QString& layerName,
   }
 }
 
-QgsMapLayer* QgsMSLayerCache::searchLayer( const QString& url, const QString& layerName )
+QgsMapLayer* QgsMSLayerCache::searchLayer( const QString& url, const QString& layerName, const QString& configFile )
 {
   QPair<QString, QString> urlNamePair = qMakePair( url, layerName );
   if ( !mEntries.contains( urlNamePair ) )
   {
-    QgsDebugMsg( "Layer not found in cache" );
+    QgsMessageLog::logMessage( "Layer '" + layerName + "' configFile: " + configFile + " not found in layer cache'", "Server", QgsMessageLog::INFO );
     return 0;
   }
   else
   {
-    QgsMSLayerCacheEntry &entry = mEntries[ urlNamePair ];
-    entry.lastUsedTime = time( NULL );
-    QgsDebugMsg( "Layer found in cache" );
-    return entry.layerPointer;
+    QList< QgsMSLayerCacheEntry > layers = mEntries.values( urlNamePair );
+    QList< QgsMSLayerCacheEntry >::iterator layerIt = layers.begin();
+    for ( ; layerIt != layers.end(); ++layerIt )
+    {
+      if ( configFile.isEmpty() || layerIt->configFile == configFile )
+      {
+        layerIt->lastUsedTime = time( NULL );
+        QgsMessageLog::logMessage( "Layer '" + layerName + "' configFile: " + configFile + " found in layer cache", "Server", QgsMessageLog::INFO );
+        return layerIt->layerPointer;
+      }
+    }
+    QgsMessageLog::logMessage( "Layer '" + layerName + "' configFile: " + configFile + " not found in layer cache'", "Server", QgsMessageLog::INFO );
+    return 0;
   }
 }
 
 void QgsMSLayerCache::removeProjectFileLayers( const QString& project )
 {
+  QgsMessageLog::logMessage( "Removing cache entries for project file: " + project, "Server", QgsMessageLog::INFO );
   QList< QPair< QString, QString > > removeEntries;
+  QList< QgsMSLayerCacheEntry > removeEntriesValues;
 
   QHash<QPair<QString, QString>, QgsMSLayerCacheEntry>::iterator entryIt = mEntries.begin();
   for ( ; entryIt != mEntries.end(); ++entryIt )
   {
     if ( entryIt.value().configFile == project )
     {
       removeEntries.push_back( entryIt.key() );
+      removeEntriesValues.push_back( entryIt.value() );
       freeEntryRessources( entryIt.value() );
     }
   }
 
-  QList< QPair< QString, QString > >::const_iterator removeIt = removeEntries.constBegin();
-  for ( ; removeIt != removeEntries.constEnd(); ++removeIt )
+  for ( int i = 0; i < removeEntries.size(); ++i )
   {
-    mEntries.remove( *removeIt );
+    const QgsMSLayerCacheEntry& removeEntry = removeEntriesValues.at( i );
+    const QPair< QString, QString > removeKey = removeEntries.at( i );
+    QgsMessageLog::logMessage( "Removing cache entry for url:" +  removeKey.first + " layerName:" + removeKey.second + " project file:" + project, "Server", QgsMessageLog::INFO );
+    mEntries.remove( removeKey, removeEntry );
   }
 }
 
@@ -149,12 +159,11 @@ void QgsMSLayerCache::updateEntries()
 
 void QgsMSLayerCache::removeLeastUsedEntry()
 {
-
   if ( mEntries.size() < 1 )
   {
     return;
   }
-  QgsDebugMsg( "removeLeastUsedEntry" );
+
   QHash<QPair<QString, QString>, QgsMSLayerCacheEntry>::iterator it = mEntries.begin();
   QHash<QPair<QString, QString>, QgsMSLayerCacheEntry>::iterator lowest_it = it;
   time_t lowest_time = it->lastUsedTime;
@@ -168,6 +177,7 @@ void QgsMSLayerCache::removeLeastUsedEntry()
     }
   }
 
+  QgsMessageLog::logMessage( "Removing last accessed layer '" + lowest_it.value().layerPointer->name() + "' project file " + lowest_it.value().configFile + " from cache" , "Server", QgsMessageLog::INFO );
   freeEntryRessources( *lowest_it );
   mEntries.erase( lowest_it );
 }
@@ -203,3 +213,13 @@ void QgsMSLayerCache::freeEntryRessources( QgsMSLayerCacheEntry& entry )
     }
   }
 }
+
+void QgsMSLayerCache::logCacheContents() const
+{
+  QgsMessageLog::logMessage( "Layer cache contents:" , "Server", QgsMessageLog::INFO );
+  QHash<QPair<QString, QString>, QgsMSLayerCacheEntry>::const_iterator it = mEntries.constBegin();
+  for ( ; it != mEntries.constEnd(); ++it )
+  {
+    QgsMessageLog::logMessage( "Url: " + it.value().url + " Layer name: " + it.value().layerPointer->name() + " Project: " + it.value().configFile, "Server", QgsMessageLog::INFO );
+  }
+}

src/server/qgsmslayercache.h

@@ -20,7 +20,7 @@
 
 #include <time.h>
 #include <QFileSystemWatcher>
-#include <QHash>
+#include <QMultiHash>
 #include <QObject>
 #include <QPair>
 #include <QString>
@@ -35,9 +35,19 @@ struct QgsMSLayerCacheEntry
   QgsMapLayer* layerPointer;
   QList<QString> temporaryFiles; //path to the temporary files written for the layer
   QString configFile; //path to the project file associated with the layer
+
+  bool operator==( const QgsMSLayerCacheEntry& other ) const
+  {
+    return ( creationTime == other.creationTime
+             && lastUsedTime == other.lastUsedTime
+             && url == other.url
+             && layerPointer == other.layerPointer
+             && temporaryFiles == other.temporaryFiles
+             && configFile == other.configFile );
+  }
 };
 
-/**A singleton class that caches layer objects for the
+/** A singleton class that caches layer objects for the
 QGIS mapserver*/
 class QgsMSLayerCache: public QObject
 {
@@ -46,53 +56,56 @@ class QgsMSLayerCache: public QObject
     static QgsMSLayerCache* instance();
     ~QgsMSLayerCache();
 
-    /**Inserts a new layer into the cash
+    /** Inserts a new layer into the cash
     @param url the layer datasource
     @param layerName the layer name (to distinguish between different layers in a request using the same datasource
     @param configFile path of the config file (to invalidate entries if file changes). Can be empty (e.g. layers from sld)
     @param tempFiles some layers have temporary files. The cash makes sure they are removed when removing the layer from the cash*/
     void insertLayer( const QString& url, const QString& layerName, QgsMapLayer* layer, const QString& configFile = QString(), const QList<QString>& tempFiles = QList<QString>() );
-    /**Searches for the layer with the given url.
+    /** Searches for the layer with the given url.
      @return a pointer to the layer or 0 if no such layer*/
-    QgsMapLayer* searchLayer( const QString& url, const QString& layerName );
+    QgsMapLayer* searchLayer( const QString& url, const QString& layerName, const QString& configFile = QString() );
 
     int projectsMaxLayers() const { return mProjectMaxLayers; }
 
     void setProjectMaxLayers( int n ) { mProjectMaxLayers = n; }
 
+    //for debugging
+    void logCacheContents() const;
+
   protected:
-    /**Protected singleton constructor*/
+    /** Protected singleton constructor*/
     QgsMSLayerCache();
-    /**Goes through the list and removes entries and layers
+    /** Goes through the list and removes entries and layers
      depending on their time stamps and the number of other
     layers*/
     void updateEntries();
-    /**Removes the cash entry with the lowest 'lastUsedTime'*/
+    /** Removes the cash entry with the lowest 'lastUsedTime'*/
     void removeLeastUsedEntry();
-    /**Frees memory and removes temporary files of an entry*/
+    /** Frees memory and removes temporary files of an entry*/
     void freeEntryRessources( QgsMSLayerCacheEntry& entry );
 
   private:
-    /**Cash entries with pair url/layer name as a key. The layer name is necessary for cases where the same
+    /** Cash entries with pair url/layer name as a key. The layer name is necessary for cases where the same
       url is used several time in a request. It ensures that different layer instances are created for different
       layer names*/
-    QHash<QPair<QString, QString>, QgsMSLayerCacheEntry> mEntries;
+    QMultiHash<QPair<QString, QString>, QgsMSLayerCacheEntry> mEntries;
 
-    /**Config files used in the cache (with reference counter)*/
+    /** Config files used in the cache (with reference counter)*/
     QHash< QString, int > mConfigFiles;
 
-    /**Check for configuration file updates (remove layers from cache if configuration file changes)*/
+    /** Check for configuration file updates (remove layers from cache if configuration file changes)*/
     QFileSystemWatcher mFileSystemWatcher;
 
-    /**Maximum number of layers in the cache*/
+    /** Maximum number of layers in the cache*/
     int mDefaultMaxLayers;
 
-    /**Maximum number of layers in the cache, overrides DEFAULT_MAX_N_LAYERS if larger*/
+    /** Maximum number of layers in the cache, overrides DEFAULT_MAX_N_LAYERS if larger*/
     int mProjectMaxLayers;
 
   private slots:
 
-    /**Removes entries from a project (e.g. if a project file has changed)*/
+    /** Removes entries from a project (e.g. if a project file has changed)*/
     void removeProjectFileLayers( const QString& project );
 };
 

src/server/qgsserver.cpp

@@ -394,6 +394,8 @@ bool QgsServer::init( int & argc, char ** argv )
   }
 #endif
 
+  QgsServerLogger::instance();
+
   QgsEditorWidgetRegistry::initEditors();
   mInitialised = TRUE;
   return TRUE;

src/server/qgsserverprojectparser.cpp

@@ -221,7 +221,7 @@ QgsMapLayer* QgsServerProjectParser::createLayerFromElement( const QDomElement&
   QgsMapLayer* layer = 0;
   if ( useCache )
   {
-    layer = QgsMSLayerCache::instance()->searchLayer( absoluteUri, id );
+    layer = QgsMSLayerCache::instance()->searchLayer( absoluteUri, id, mProjectPath );
   }
 
   if ( layer )