use file filters from MDAL

python/core/auto_generated/qgsproviderregistry.sip.in

@@ -181,6 +181,32 @@ buildSupportedRasterFileFilter to a string, which is then returned.
    This replaces :py:func:`QgsRasterLayer.buildSupportedRasterFileFilter()`
 %End
 
+    virtual QString fileMeshFilters() const;
+%Docstring
+Returns mesh file filter string
+
+Returns a string suitable for a QFileDialog of mesh file formats
+supported by all data providers.
+
+This walks through all data providers appending calls to their
+fileMeshFilters to a string, which is then returned.
+
+.. versionadded:: 3.6
+%End
+
+    virtual QString fileMeshDatasetFilters() const;
+%Docstring
+Returns mesh's dataset file filter string
+
+Returns a string suitable for a QFileDialog of mesh datasets file formats
+supported by all data providers.
+
+This walks through all data providers appending calls to their
+fileMeshFilters to a string, which is then returned.
+
+.. versionadded:: 3.6
+%End
+
     virtual QString databaseDrivers() const;
 %Docstring
 Returns a string containing the available database drivers

src/app/mesh/qgsmeshlayerproperties.cpp

@@ -31,6 +31,7 @@
 #include "qgsprojectionselectiondialog.h"
 #include "qgsrenderermeshpropertieswidget.h"
 #include "qgssettings.h"
+#include "qgsproviderregistry.h"
 
 #include <QFileDialog>
 #include <QMessageBox>
@@ -137,7 +138,7 @@ void QgsMeshLayerProperties::addDataset()
   QString openFileString = QFileDialog::getOpenFileName( nullptr,
                            tr( "Load mesh datasets" ),
                            openFileDir,
-                           QStringLiteral( "All files(*.*);;Results Files XMDF(*.xmdf);;Results Files DAT(*.dat)" ) );
+                           QgsProviderRegistry::instance()->fileMeshDatasetFilters() );
 
   if ( openFileString.isEmpty() )
   {

src/core/qgsproviderregistry.cpp

@@ -38,6 +38,7 @@ typedef QString providerkey_t();
 typedef QString description_t();
 typedef bool    isprovider_t();
 typedef QString fileVectorFilters_t();
+typedef void fileMeshFilters_t( QString &fileMeshFiltersString, QString &fileMeshDatasetFiltersString );
 typedef void buildsupportedrasterfilefilter_t( QString &fileFiltersString );
 typedef QString databaseDrivers_t();
 typedef QString directoryDrivers_t();
@@ -233,6 +234,23 @@ void QgsProviderRegistry::init()
       QgsDebugMsg( QStringLiteral( "Checking %1: ...loaded OK (%2 file filters)" ).arg( myLib.fileName() ).arg( fileRasterFilters.split( ";;" ).count() ) );
     }
 
+    // now get mesh file filters, if any
+    fileMeshFilters_t *pFileMeshFilters = reinterpret_cast< fileMeshFilters_t * >( cast_to_fptr( myLib.resolve( "fileMeshFilters" ) ) );
+    if ( pFileMeshFilters )
+    {
+      QString fileMeshFilters;
+      QString fileMeshDatasetFilters;
+
+      pFileMeshFilters( fileMeshFilters, fileMeshDatasetFilters );
+
+      if ( !fileMeshFilters.isEmpty() )
+        mMeshFileFilters += fileMeshFilters;
+      if ( !fileMeshDatasetFilters.isEmpty() )
+        mMeshDatasetFileFilters += fileMeshDatasetFilters;
+
+      QgsDebugMsg( QStringLiteral( "Checking %1: ...loaded OK (%2 file mesh filters, %3 file dataset filters)" ).arg( myLib.fileName() ).arg( mMeshFileFilters.split( ";;" ).count() ).arg( mMeshDatasetFileFilters.split( ";;" ).count() ) );
+    }
+
     // call initProvider() if such function is available - allows provider to register its services to QGIS
     initProviderFunction_t *initFunc = reinterpret_cast< initProviderFunction_t * >( cast_to_fptr( myLib.resolve( "initProvider" ) ) );
     if ( initFunc )
@@ -574,6 +592,16 @@ QString QgsProviderRegistry::fileRasterFilters() const
   return mRasterFileFilters;
 }
 
+QString QgsProviderRegistry::fileMeshFilters() const
+{
+  return mMeshFileFilters;
+}
+
+QString QgsProviderRegistry::fileMeshDatasetFilters() const
+{
+  return mMeshDatasetFileFilters;
+}
+
 QString QgsProviderRegistry::databaseDrivers() const
 {
   return mDatabaseDrivers;

src/core/qgsproviderregistry.h

@@ -180,6 +180,32 @@ class CORE_EXPORT QgsProviderRegistry
      */
     virtual QString fileRasterFilters() const;
 
+    /**
+     * Returns mesh file filter string
+
+      Returns a string suitable for a QFileDialog of mesh file formats
+      supported by all data providers.
+
+      This walks through all data providers appending calls to their
+      fileMeshFilters to a string, which is then returned.
+
+      \since QGIS 3.6
+     */
+    virtual QString fileMeshFilters() const;
+
+    /**
+     * Returns mesh's dataset file filter string
+
+      Returns a string suitable for a QFileDialog of mesh datasets file formats
+      supported by all data providers.
+
+      This walks through all data providers appending calls to their
+      fileMeshFilters to a string, which is then returned.
+
+      \since QGIS 3.6
+     */
+    virtual QString fileMeshDatasetFilters() const;
+
     //! Returns a string containing the available database drivers
     virtual QString databaseDrivers() const;
     //! Returns a string containing the available directory drivers
@@ -257,6 +283,16 @@ class CORE_EXPORT QgsProviderRegistry
      */
     QString mRasterFileFilters;
 
+    /**
+     * File filter string for raster files
+     */
+    QString mMeshFileFilters;
+
+    /**
+     * File filter string for raster files
+     */
+    QString mMeshDatasetFileFilters;
+
     /**
      * Available database drivers string for vector databases
      *

src/providers/mdal/qgsmdalprovider.cpp

@@ -19,6 +19,7 @@
 
 #include "qgsmdalprovider.h"
 #include "qgstriangularmesh.h"
+#include "qgslogger.h"
 
 #ifdef HAVE_GUI
 #include "qgssourceselectprovider.h"
@@ -170,6 +171,76 @@ QgsRectangle QgsMdalProvider::extent() const
   return ret;
 }
 
+void QgsMdalProvider::fileMeshFilters( QString &fileMeshFiltersString, QString &fileMeshDatasetFiltersString )
+{
+  DriverH mdalDriver;
+
+  // Grind through all the drivers and their respective metadata.
+  // We'll add a file filter for those drivers that have a file
+  // extension defined for them; the others, well, even though
+  // theoreticaly we can open those files because there exists a
+  // driver for them, the user will have to use the "All Files" to
+  // open datasets with no explicitly defined file name extension.
+
+  fileMeshFiltersString.clear();
+  fileMeshDatasetFiltersString.clear();
+
+  int driverCount = MDAL_driverCount();
+
+  QgsDebugMsg( QStringLiteral( "MDAL driver count: %1" ).arg( driverCount ) );
+
+  for ( int i = 0; i < driverCount; ++i )
+  {
+    mdalDriver = MDAL_driverFromIndex( i );
+    if ( !mdalDriver )
+    {
+      QgsLogger::warning( "unable to get driver " + QString::number( i ) );
+      continue;
+    }
+
+    QString longName = MDAL_DR_longName( mdalDriver );
+    QString driverFilters = MDAL_DR_filters( mdalDriver );
+    driverFilters = driverFilters.replace( QStringLiteral( ";;" ), QStringLiteral( " " ) );
+
+    bool isMeshDriver = MDAL_DR_meshLoadCapability( mdalDriver );
+
+    if ( longName.isEmpty() )
+    {
+      QgsLogger::warning( "invalid driver long name " + QString::number( i ) );
+      continue;
+    }
+
+    if ( !driverFilters.isEmpty() )
+    {
+      QString driverFilter = longName + " (" + driverFilters + ");;";
+      if ( isMeshDriver )
+        fileMeshFiltersString += driverFilter;
+      else
+        fileMeshDatasetFiltersString += driverFilter;
+    }
+  }
+
+  // sort file filters alphabetically
+  QStringList filters = fileMeshFiltersString.split( QStringLiteral( ";;" ), QString::SkipEmptyParts );
+  filters.sort();
+  fileMeshFiltersString = filters.join( QStringLiteral( ";;" ) ) + ";;";
+
+  filters = fileMeshDatasetFiltersString.split( QStringLiteral( ";;" ), QString::SkipEmptyParts );
+  filters.sort();
+  fileMeshDatasetFiltersString = filters.join( QStringLiteral( ";;" ) ) + ";;";
+
+  // can't forget the default case - first
+  fileMeshFiltersString.prepend( QObject::tr( "All files" ) + " (*);;" );
+  fileMeshDatasetFiltersString.prepend( QObject::tr( "All files" ) + " (*);;" );
+
+  // cleanup
+  if ( fileMeshFiltersString.endsWith( QLatin1String( ";;" ) ) ) fileMeshFiltersString.chop( 2 );
+  if ( fileMeshDatasetFiltersString.endsWith( QLatin1String( ";;" ) ) ) fileMeshDatasetFiltersString.chop( 2 );
+
+  QgsDebugMsg( "Mesh filter list built: " + fileMeshFiltersString );
+  QgsDebugMsg( "Mesh dataset filter list built: " + fileMeshDatasetFiltersString );
+}
+
 /*----------------------------------------------------------------------------------------------*/
 
 bool QgsMdalProvider::addDataset( const QString &uri )
@@ -394,4 +465,20 @@ QGISEXTERN QList<QgsSourceSelectProvider *> *sourceSelectProviders()
   return providers;
 }
 
+/**
+  Builds the list of mesh file filter strings
+
+  We query MDAL for a list of supported mesh formats; we then build
+  a list of file filter strings from that list to be used for meshes and
+  also one for datasets. We return a strings
+  that contains this list that is suitable for use in a
+  QFileDialog::getOpenFileNames() call.
+
+  \since QGIS 3.6
+*/
+QGISEXTERN void fileMeshFilters( QString &fileMeshFiltersString, QString &fileMeshDatasetFiltersString )
+{
+  QgsMdalProvider::fileMeshFilters( fileMeshFiltersString, fileMeshDatasetFiltersString );
+}
+
 #endif

src/providers/mdal/qgsmdalprovider.h

@@ -69,6 +69,13 @@ class QgsMdalProvider : public QgsMeshDataProvider
     QgsMeshDataBlock areFacesActive( QgsMeshDatasetIndex index, int faceIndex, int count ) const override;
     QgsRectangle extent() const override;
 
+    /**
+     * Returns filters for meshes and datasets to be used in Open File Dialogs
+     * \param fileMeshFiltersString file mesh filters
+     * \param fileMeshDatasetFiltersString file mesh datasets filters
+     */
+    static void fileMeshFilters( QString &fileMeshFiltersString, QString &fileMeshDatasetFiltersString );
+
   private:
     QVector<QgsMeshVertex> vertices( ) const;
     QVector<QgsMeshFace> faces( ) const;

src/providers/mdal/qgsmdalsourceselect.cpp

@@ -28,7 +28,7 @@ QgsMdalSourceSelect::QgsMdalSourceSelect( QWidget *parent, Qt::WindowFlags fl, Q
   setupButtons( buttonBox );
 
   mFileWidget->setDialogTitle( tr( "Open MDAL Supported Mesh Dataset(s)" ) );
-  mFileWidget->setFilter( tr( "All Files (*);;GRIB File (*.grb *.grb2 *.bin *.grib *.grib1 *.grib2);;NetCDF File (*.nc);;2DM Mesh File (*.2dm);;3Di Results (results_3di.nc)" ) );
+  mFileWidget->setFilter( QgsProviderRegistry::instance()->fileMeshFilters() );
   mFileWidget->setStorageMode( QgsFileWidget::GetMultipleFiles );
   connect( mFileWidget, &QgsFileWidget::fileChanged, this, [ = ]( const QString & path )
   {

tests/src/providers/CMakeLists.txt

@@ -15,12 +15,14 @@ INCLUDE_DIRECTORIES(${CMAKE_CURRENT_SOURCE_DIR}
   ${CMAKE_SOURCE_DIR}/src/providers/wms
   ${CMAKE_SOURCE_DIR}/src/providers/postgres
   ${CMAKE_SOURCE_DIR}/src/providers/arcgisrest
+  ${CMAKE_SOURCE_DIR}/src/providers/mdal
   ${CMAKE_SOURCE_DIR}/src/test
   ${CMAKE_BINARY_DIR}/src/core
 )
 INCLUDE_DIRECTORIES(SYSTEM
   ${QT_INCLUDE_DIR}
   ${GDAL_INCLUDE_DIR}
+  ${MDAL_INCLUDE_DIR}
   ${QCA_INCLUDE_DIR}
   ${QTKEYCHAIN_INCLUDE_DIR}
   ${POSTGRES_INCLUDE_DIR}
@@ -85,6 +87,8 @@ TARGET_LINK_LIBRARIES(qgis_postgresprovidertest postgresprovider_a)
 ADD_QGIS_TEST(postgresconntest testqgspostgresconn.cpp)
 TARGET_LINK_LIBRARIES(qgis_postgresconntest postgresprovider_a)
 
+ADD_QGIS_TEST(mdalprovidertest testqgsmdalprovider.cpp)
+
 #############################################################
 # WCS public servers test:
 # No need to test on all platforms

tests/src/providers/testqgsmdalprovider.cpp

@@ -0,0 +1,87 @@
+/***************************************************************************
+     testqgsmdalprovider.cpp
+     --------------------------------------
+    Date                 : Decemeber 2018
+    Copyright            : (C) 2018 by Peter Petrik
+    Email                : zilolv@gmail.com
+ ***************************************************************************
+ *                                                                         *
+ *   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.                                   *
+ *                                                                         *
+ ***************************************************************************/
+
+#include <limits>
+
+#include "qgstest.h"
+#include <QObject>
+#include <QString>
+#include <QStringList>
+#include <QApplication>
+#include <QFileInfo>
+#include <QDir>
+
+//qgis includes...
+#include <qgis.h>
+#include <qgsapplication.h>
+#include <qgsproviderregistry.h>
+
+/**
+ * \ingroup UnitTests
+ * This is a unit test for the gdal provider
+ */
+class TestQgsMdalProvider : public QObject
+{
+    Q_OBJECT
+
+  private slots:
+    void initTestCase();// will be called before the first testfunction is executed.
+    void cleanupTestCase();// will be called after the last testfunction was executed.
+    void init() {}// will be called before each testfunction is executed.
+    void cleanup() {}// will be called after every testfunction.
+
+    void filters();
+
+  private:
+    QString mTestDataDir;
+    QString mReport;
+};
+
+//runs before all tests
+void TestQgsMdalProvider::initTestCase()
+{
+  // init QGIS's paths - true means that all path will be inited from prefix
+  QgsApplication::init();
+  QgsApplication::initQgis();
+
+  mTestDataDir = QStringLiteral( TEST_DATA_DIR ) + '/'; //defined in CmakeLists.txt
+  mReport = QStringLiteral( "<h1>MDAL Provider Tests</h1>\n" );
+}
+
+//runs after all tests
+void TestQgsMdalProvider::cleanupTestCase()
+{
+  QgsApplication::exitQgis();
+  QString myReportFile = QDir::tempPath() + "/qgistest.html";
+  QFile myFile( myReportFile );
+  if ( myFile.open( QIODevice::WriteOnly | QIODevice::Append ) )
+  {
+    QTextStream myQTextStream( &myFile );
+    myQTextStream << mReport;
+    myFile.close();
+  }
+}
+
+void TestQgsMdalProvider::filters()
+{
+  QString meshFilters = QgsProviderRegistry::instance()->fileMeshFilters();
+  QVERIFY(meshFilters.contains("*.2dm"));
+
+  QString datasetFilters = QgsProviderRegistry::instance()->fileMeshDatasetFilters();
+  QVERIFY(datasetFilters.contains("*.dat"));
+}
+
+QGSTEST_MAIN( TestQgsMdalProvider )
+#include "testqgsmdalprovider.moc"