[FEATURE] [WFS provider] Major overhaul to add WFS 1.1 and 2.0 support

First part of qgis/QGIS-Enhancement-Proposals#53
(QEP 35: WFS provider enhancements)

Improvements:
- Version autodetection
- On-disk caching of downloaded features
- Background download and progressive rendering
- WFS 1.1 and 2.0 support
- WFS 2.0 GetFeature paging
- Add provider tests

Fixes:
- qgis#10106: Panning a non-cached WFS layer causes selection to change
- qgis#9444: WFS client not requesting new features when not-cached
 qgis#14156: WFS non cached: infinite flashing
- qgis#9450 : New WFS connection option - Max number of features returned
- qgis#14122: Implement WFS 2.0 client provider (partial. no joins or stored queries)

Not in scope: WFS-T 1.1 and 2.0. But WFS-T 1.0 kept (and tested)

ci/travis/linux/qt5/blacklist.txt

@@ -66,6 +66,7 @@ PyQgsVectorFileWriter
 PyQgsVectorLayer
 PyQgsVirtualLayerDefinition
 PyQgsVirtualLayerProvider
+PyQgsWFSProvider
 PyQgsZonalStatistics
 qgis_alignrastertest
 qgis_composereffectstest

src/core/qgsowsconnection.h

@@ -59,7 +59,7 @@ class CORE_EXPORT QgsOWSConnection : public QObject
     //! @deprecated use mConnectionInfo instead
     Q_DECL_DEPRECATED QString connectionInfo();
 
-  private:
+  protected:
     QgsDataSourceURI mUri;
     QString mService;
 };

src/core/qgsvectorlayer.h

@@ -195,15 +195,23 @@ struct CORE_EXPORT QgsVectorJoinInfo
  *
  * Used to access data provided by a web feature service.
  *
- * The url can be a HTTP url to a WFS 1.0.0 server or a GML2 data file path.
- * Examples are http://foobar/wfs or /foo/bar/file.gml
- *
- * If a GML2 file path is provided the driver will attempt to read the schema from a
- * file in the same directory with the same basename + “.xsd”. This xsd file must be
- * in the same format as a WFS describe feature type response. If no xsd file is provide
- * then the driver will attempt to guess the attribute types from the file.
- *
- * In the case of a HTTP URL the ‘FILTER’ query string parameter can be used to filter
+ * The url can be a HTTP url to a WFS server (legacy, e.g. http://foobar/wfs?TYPENAME=xxx&SRSNAME=yyy[&FILTER=zzz]), or,
+ * starting with QGIS 2.16, a URI constructed using the QgsDataSourceURI class with the following parameters :
+ * - url=string (mandatory): HTTP url to a WFS server endpoint. e.g http://foobar/wfs
+ * - typename=string (mandatory): WFS typename
+ * - srsname=string (recommended): SRS like 'EPSG:XXXX'
+ * - username=string
+ * - password=string
+ * - authcfg=string
+ * - version=auto/1.0.0/1.1.0/2.0.0
+ * - filter=string: QGIS expression or OGC/FES filter
+ * - retrictToRequestBBOX=1: to download only features in the view extent (or more generally
+ *   in the bounding box of the feature iterator)
+ * - maxNumFeatures=number
+ * - IgnoreAxisOrientation=1: to ignore EPSG axis order for WFS 1.1 or 2.0
+ * - InvertAxisOrientation=1: to invert axis order
+ *
+ * The ‘FILTER’ query string parameter can be used to filter
  * the WFS feature type. The ‘FILTER’ key value can either be a QGIS expression
  * or an OGC XML filter. If the value is set to a QGIS expression the driver will
  * turn it into OGC XML filter before passing it to the WFS server. Beware the

src/gui/qgsnewhttpconnection.cpp

@@ -50,6 +50,12 @@ QgsNewHttpConnection::QgsNewHttpConnection(
   cmbDpiMode->addItem( tr( "UMN" ) );
   cmbDpiMode->addItem( tr( "GeoServer" ) );
 
+  cmbVersion->clear();
+  cmbVersion->addItem( tr( "Auto-detect" ) );
+  cmbVersion->addItem( tr( "1.0" ) );
+  cmbVersion->addItem( tr( "1.1" ) );
+  cmbVersion->addItem( tr( "2.0" ) );
+
   mAuthConfigSelect = new QgsAuthConfigSelect( this );
   tabAuth->insertTab( 1, mAuthConfigSelect, tr( "Configurations" ) );
 
@@ -92,7 +98,18 @@ QgsNewHttpConnection::QgsNewHttpConnection(
     }
     cmbDpiMode->setCurrentIndex( dpiIdx );
 
+    QString version = settings.value( key + "/version" ).toString();
+    int versionIdx = 0; // AUTO
+    if ( version == "1.0.0" )
+      versionIdx = 1;
+    else if ( version == "1.1.0" )
+      versionIdx = 2;
+    else if ( version == "2.0.0" )
+      versionIdx = 3;
+    cmbVersion->setCurrentIndex( versionIdx );
+
     txtReferer->setText( settings.value( key + "/referer" ).toString() );
+    txtMaxNumFeatures->setText( settings.value( key + "/maxnumfeatures" ).toString() );
 
     txtUserName->setText( settings.value( credentialsKey + "/username" ).toString() );
     txtPassword->setText( settings.value( credentialsKey + "/password" ).toString() );
@@ -107,6 +124,20 @@ QgsNewHttpConnection::QgsNewHttpConnection(
 
   if ( mBaseKey != "/Qgis/connections-wms/" )
   {
+    if ( mBaseKey != "/Qgis/connections-wcs/" &&
+         mBaseKey != "/Qgis/connections-wfs/" )
+    {
+      cbxIgnoreAxisOrientation->setVisible( false );
+      cbxInvertAxisOrientation->setVisible( false );
+      mGroupBox->layout()->removeWidget( cbxIgnoreAxisOrientation );
+      mGroupBox->layout()->removeWidget( cbxInvertAxisOrientation );
+    }
+
+    if ( mBaseKey == "/Qgis/connections-wfs/" )
+    {
+      cbxIgnoreAxisOrientation->setText( tr( "Ignore axis orientation (WFS 1.1/WFS 2.0)" ) );
+    }
+
     if ( mBaseKey == "/Qgis/connections-wcs/" )
     {
       cbxIgnoreGetMapURI->setText( tr( "Ignore GetCoverage URI reported in capabilities" ) );
@@ -115,12 +146,8 @@ QgsNewHttpConnection::QgsNewHttpConnection(
     else
     {
       cbxIgnoreGetMapURI->setVisible( false );
-      cbxIgnoreAxisOrientation->setVisible( false );
-      cbxInvertAxisOrientation->setVisible( false );
       cbxSmoothPixmapTransform->setVisible( false );
       mGroupBox->layout()->removeWidget( cbxIgnoreGetMapURI );
-      mGroupBox->layout()->removeWidget( cbxIgnoreAxisOrientation );
-      mGroupBox->layout()->removeWidget( cbxInvertAxisOrientation );
       mGroupBox->layout()->removeWidget( cbxSmoothPixmapTransform );
     }
 
@@ -136,13 +163,23 @@ QgsNewHttpConnection::QgsNewHttpConnection(
     mGroupBox->layout()->removeWidget( txtReferer );
     lblReferer->setVisible( false );
     mGroupBox->layout()->removeWidget( lblReferer );
+  }
 
-    // Adjust height
-    int w = width();
-    adjustSize();
-    resize( w, height() );
+  if ( mBaseKey != "/Qgis/connections-wfs/" )
+  {
+    cmbVersion->setVisible( false );
+    mGroupBox->layout()->removeWidget( cmbVersion );
+    lblMaxNumFeatures->setVisible( false );
+    mGroupBox->layout()->removeWidget( lblMaxNumFeatures );
+    txtMaxNumFeatures->setVisible( false );
+    mGroupBox->layout()->removeWidget( txtMaxNumFeatures );
   }
 
+  // Adjust height
+  int w = width();
+  adjustSize();
+  resize( w, height() );
+
   on_txtName_textChanged( connName );
 }
 
@@ -219,11 +256,18 @@ void QgsNewHttpConnection::accept()
   }
 
   settings.setValue( key + "/url", url.toString() );
-  if ( mBaseKey == "/Qgis/connections-wms/" || mBaseKey == "/Qgis/connections-wcs/" )
+
+  if ( mBaseKey == "/Qgis/connections-wms/" ||
+       mBaseKey == "/Qgis/connections-wcs/" ||
+       mBaseKey == "/Qgis/connections-wfs/" )
   {
-    settings.setValue( key + "/ignoreGetMapURI", cbxIgnoreGetMapURI->isChecked() );
     settings.setValue( key + "/ignoreAxisOrientation", cbxIgnoreAxisOrientation->isChecked() );
     settings.setValue( key + "/invertAxisOrientation", cbxInvertAxisOrientation->isChecked() );
+  }
+
+  if ( mBaseKey == "/Qgis/connections-wms/" || mBaseKey == "/Qgis/connections-wcs/" )
+  {
+    settings.setValue( key + "/ignoreGetMapURI", cbxIgnoreGetMapURI->isChecked() );
     settings.setValue( key + "/smoothPixmapTransform", cbxSmoothPixmapTransform->isChecked() );
 
     int dpiMode = 0;
@@ -252,6 +296,28 @@ void QgsNewHttpConnection::accept()
   {
     settings.setValue( key + "/ignoreGetFeatureInfoURI", cbxIgnoreGetFeatureInfoURI->isChecked() );
   }
+  if ( mBaseKey == "/Qgis/connections-wfs/" )
+  {
+    QString version = "auto";
+    switch ( cmbVersion->currentIndex() )
+    {
+      case 0:
+        version = "auto";
+        break;
+      case 1:
+        version = "1.0.0";
+        break;
+      case 2:
+        version = "1.1.0";
+        break;
+      case 3:
+        version = "2.0.0";
+        break;
+    }
+    settings.setValue( key + "/version", version );
+
+    settings.setValue( key + "/maxnumfeatures", txtMaxNumFeatures->text() );
+  }
 
   settings.setValue( key + "/referer", txtReferer->text() );
 

src/providers/wfs/CMakeLists.txt

@@ -8,6 +8,14 @@ SET(WFS_SRCS
   qgswfsdataitems.cpp
   qgswfsfeatureiterator.cpp
   qgswfssourceselect.cpp
+  qgswfsrequest.cpp
+  qgswfsconnection.cpp
+  qgswfsdatasourceuri.cpp
+  qgswfsconstants.cpp
+  qgswfsdescribefeaturetype.cpp
+  qgswfsshareddata.cpp
+  qgswfstransactionrequest.cpp
+  qgswfsutils.cpp
 )
 
 SET (WFS_MOC_HDRS
@@ -16,6 +24,11 @@ SET (WFS_MOC_HDRS
   qgswfsprovider.h
   qgswfsfeatureiterator.h
   qgswfssourceselect.h
+  qgswfsrequest.h
+  qgswfsdescribefeaturetype.h
+  qgswfstransactionrequest.h
+  qgswfsshareddata.h
+  qgswfsutils.h
 )
 
 ########################################################
@@ -27,6 +40,7 @@ INCLUDE_DIRECTORIES (
   ../../core
   ../../core/auth
   ../../core/geometry
+  ../../core/symbology-ng  # needed by qgsvectorfilewriter.h
   ../../gui
   ../../gui/auth
   ${CMAKE_CURRENT_BINARY_DIR}/../../ui
@@ -37,6 +51,8 @@ INCLUDE_DIRECTORIES(SYSTEM
   ${EXPAT_INCLUDE_DIR}
   ${QSCINTILLA_INCLUDE_DIR}
   ${QCA_INCLUDE_DIR}
+  ${GDAL_INCLUDE_DIR} # needed by qgsvectorfilewriter.h
+  ${SQLITE3_INCLUDE_DIR}
 )
 
 ADD_LIBRARY (wfsprovider MODULE ${WFS_SRCS} ${WFS_MOC_SRCS})