[FEATURE]: use file watcher in wms server to check for updates in project files

mhugent · mhugent · commit d4109ce2dcec · 2011-05-13T14:12:29.000+02:00
diff --git a/src/mapserver/CMakeLists.txt b/src/mapserver/CMakeLists.txt
@@ -62,6 +62,7 @@ SET ( qgis_mapserv_SRCS
 
 SET (qgis_mapserv_MOC_HDRS
   qgsftptransaction.h
+  qgsconfigcache.h
 )
 
 SET (qgis_mapserv_RCCS 
diff --git a/src/mapserver/qgsconfigcache.cpp b/src/mapserver/qgsconfigcache.cpp
@@ -20,9 +20,11 @@
 #include "qgsmslayercache.h"
 #include "qgsprojectparser.h"
 #include "qgssldparser.h"
+#include <QCoreApplication>
 
 QgsConfigCache::QgsConfigCache()
 {
+  QObject::connect( &mFileSystemWatcher, SIGNAL( fileChanged( const QString& ) ), this, SLOT( removeChangedEntry( const QString& ) ) );
 }
 
 QgsConfigCache::~QgsConfigCache()
@@ -36,6 +38,7 @@ QgsConfigCache::~QgsConfigCache()
 
 QgsConfigParser* QgsConfigCache::searchConfiguration( const QString& filePath )
 {
+  QCoreApplication::processEvents(); //check for updates from file system watcher
   QgsConfigParser* p = 0;
   QHash<QString, QgsConfigParser*>::const_iterator configIt = mCachedConfigurations.find( filePath );
   if ( configIt == mCachedConfigurations.constEnd() )
@@ -63,7 +66,12 @@ QgsConfigParser* QgsConfigCache::insertConfiguration( const QString& filePath )
   {
     //remove a cache entry to avoid memory problems
     QHash<QString, QgsConfigParser*>::iterator configIt = mCachedConfigurations.begin();
-    mCachedConfigurations.erase( configIt );
+    if ( configIt != mCachedConfigurations.end() )
+    {
+      mFileSystemWatcher.removePath( configIt.key() );
+      delete configIt.value();
+      mCachedConfigurations.erase( configIt );
+    }
   }
 
   //first open file
@@ -107,6 +115,19 @@ QgsConfigParser* QgsConfigCache::insertConfiguration( const QString& filePath )
   }
 
   mCachedConfigurations.insert( filePath, configParser );
+  mFileSystemWatcher.addPath( filePath );
   delete configFile;
   return configParser;
 }
+
+void QgsConfigCache::removeChangedEntry( const QString& path )
+{
+  QgsMSDebugMsg( "Remove config cache entry because file changed" );
+  QHash<QString, QgsConfigParser*>::iterator configIt = mCachedConfigurations.find( path );
+  if ( configIt != mCachedConfigurations.end() )
+  {
+    delete configIt.value();
+    mCachedConfigurations.erase( configIt );
+  }
+  mFileSystemWatcher.removePath( path );
+}
diff --git a/src/mapserver/qgsconfigcache.h b/src/mapserver/qgsconfigcache.h
@@ -18,14 +18,17 @@
 #ifndef QGSCONFIGCACHE_H
 #define QGSCONFIGCACHE_H
 
+#include <QFileSystemWatcher>
 #include <QHash>
+#include <QObject>
 #include <QString>
 
 class QgsConfigParser;
 
 /**A cache for configuration XML (useful because of the mapfile parameter)*/
-class QgsConfigCache
+class QgsConfigCache: public QObject
 {
+    Q_OBJECT
   public:
     QgsConfigCache();
     ~QgsConfigCache();
@@ -40,6 +43,12 @@ class QgsConfigCache
     QgsConfigParser* insertConfiguration( const QString& filePath );
     /**Cached XML configuration documents. Key: file path, value: config parser. Default configuration has key '$default$'*/
     QHash<QString, QgsConfigParser*> mCachedConfigurations;
+    /**Check for configuration file updates (remove entry from cache if file changes)*/
+    QFileSystemWatcher mFileSystemWatcher;
+
+  private slots:
+    /**Removes changed entry from this cache*/
+    void removeChangedEntry( const QString& path );
 };
 
 #endif // QGSCONFIGCACHE_H

Original file line number	Diff line number	Diff line change
`@@ -62,6 +62,7 @@ SET ( qgis_mapserv_SRCS`
`62`	`62`
`63`	`63`	`SET (qgis_mapserv_MOC_HDRS`
`64`	`64`	`qgsftptransaction.h`
	`65`	`+ qgsconfigcache.h`
`65`	`66`	`)`
`66`	`67`
`67`	`68`	`SET (qgis_mapserv_RCCS`