Add QgsProviderUtils with a method for determining whether a list

nyalldawson · nyalldawson · commit 1355b39be0a0 · 2021-07-02T09:49:33.000+10:00
of sublayer details is incomplete and requires a more in-depth scan
diff --git a/python/core/auto_generated/providers/qgsproviderutils.sip.in b/python/core/auto_generated/providers/qgsproviderutils.sip.in
@@ -0,0 +1,45 @@
+/************************************************************************
+ * This file has been generated automatically from                      *
+ *                                                                      *
+ * src/core/providers/qgsproviderutils.h                                *
+ *                                                                      *
+ * Do not edit manually ! Edit header and run scripts/sipify.pl again   *
+ ************************************************************************/
+
+
+
+class QgsProviderUtils
+{
+%Docstring(signature="appended")
+
+Contains utility functions for working with data providers.
+
+.. versionadded:: 3.22
+%End
+
+%TypeHeaderCode
+#include "qgsproviderutils.h"
+%End
+  public:
+
+    static bool sublayerDetailsAreIncomplete( const QList< QgsProviderSublayerDetails > &details );
+%Docstring
+Returns ``True`` if the sublayer ``details`` are incomplete, and require a more in-depth
+scan.
+
+For instance, if the details contain any vector sublayers with unknown geometry types
+then a query with the Qgis.SublayerQueryFlag.ResolveGeometryType flag is required.
+%End
+
+};
+
+
+
+
+/************************************************************************
+ * This file has been generated automatically from                      *
+ *                                                                      *
+ * src/core/providers/qgsproviderutils.h                                *
+ *                                                                      *
+ * Do not edit manually ! Edit header and run scripts/sipify.pl again   *
+ ************************************************************************/
diff --git a/python/core/core_auto.sip b/python/core/core_auto.sip
@@ -516,6 +516,7 @@
 %Include auto_generated/providers/qgsproviderregistry.sip
 %Include auto_generated/providers/qgsprovidersublayerdetails.sip
 %Include auto_generated/providers/qgsprovidersublayertask.sip
+%Include auto_generated/providers/qgsproviderutils.sip
 %Include auto_generated/providers/arcgis/qgsarcgisportalutils.sip
 %Include auto_generated/providers/arcgis/qgsarcgisrestutils.sip
 %Include auto_generated/providers/memory/qgsmemoryproviderutils.sip
diff --git a/src/core/CMakeLists.txt b/src/core/CMakeLists.txt
@@ -234,6 +234,7 @@ set(QGIS_CORE_SRCS
   providers/qgsproviderregistry.cpp
   providers/qgsprovidersublayerdetails.cpp
   providers/qgsprovidersublayertask.cpp
+  providers/qgsproviderutils.cpp
 
   providers/arcgis/qgsarcgisportalutils.cpp
   providers/arcgis/qgsarcgisrestquery.cpp
@@ -1524,6 +1525,7 @@ set(QGIS_CORE_HDRS
   providers/qgsproviderregistry.h
   providers/qgsprovidersublayerdetails.h
   providers/qgsprovidersublayertask.h
+  providers/qgsproviderutils.h
 
   providers/arcgis/qgsarcgisportalutils.h
   providers/arcgis/qgsarcgisrestquery.h
diff --git a/src/core/providers/qgsproviderutils.cpp b/src/core/providers/qgsproviderutils.cpp
@@ -0,0 +1,42 @@
+/***************************************************************************
+                             qgsproviderutils.cpp
+                             ----------------------------
+    begin                : June 2021
+    copyright            : (C) 2021 by Nyall Dawson
+    email                : nyall dot dawson at gmail dot 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 "qgsproviderutils.h"
+#include "qgsprovidersublayerdetails.h"
+
+bool QgsProviderUtils::sublayerDetailsAreIncomplete( const QList<QgsProviderSublayerDetails> &details )
+{
+  for ( const QgsProviderSublayerDetails &sublayer : details )
+  {
+    switch ( sublayer.type() )
+    {
+      case QgsMapLayerType::VectorLayer:
+        if ( sublayer.wkbType() == QgsWkbTypes::Unknown )
+          return true;
+        break;
+
+      case QgsMapLayerType::RasterLayer:
+      case QgsMapLayerType::PluginLayer:
+      case QgsMapLayerType::MeshLayer:
+      case QgsMapLayerType::VectorTileLayer:
+      case QgsMapLayerType::AnnotationLayer:
+      case QgsMapLayerType::PointCloudLayer:
+        break;
+    }
+  }
+
+  return false;
+}
diff --git a/src/core/providers/qgsproviderutils.h b/src/core/providers/qgsproviderutils.h
@@ -0,0 +1,51 @@
+/***************************************************************************
+                             qgsproviderutils.h
+                             ----------------------------
+    begin                : June 2021
+    copyright            : (C) 2021 by Nyall Dawson
+    email                : nyall dot dawson at gmail dot 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.                                   *
+ *                                                                         *
+ ***************************************************************************/
+#ifndef QGSPROVIDERUTILS_H
+#define QGSPROVIDERUTILS_H
+
+#include "qgis_core.h"
+#include "qgis.h"
+#include <QList>
+
+class QgsProviderSublayerDetails;
+
+/**
+ * \class QgsProviderUtils
+ * \ingroup core
+ *
+ * \brief Contains utility functions for working with data providers.
+ *
+ * \since QGIS 3.22
+ */
+class CORE_EXPORT QgsProviderUtils
+{
+  public:
+
+    /**
+     * Returns TRUE if the sublayer \a details are incomplete, and require a more in-depth
+     * scan.
+     *
+     * For instance, if the details contain any vector sublayers with unknown geometry types
+     * then a query with the Qgis::SublayerQueryFlag::ResolveGeometryType flag is required.
+     */
+    static bool sublayerDetailsAreIncomplete( const QList< QgsProviderSublayerDetails > &details );
+
+};
+
+#endif //QGSPROVIDERUTILS_H
+
+
+
diff --git a/tests/src/python/CMakeLists.txt b/tests/src/python/CMakeLists.txt
@@ -269,6 +269,7 @@ ADD_PYTHON_TEST(PyQgsPolymorphicRelation test_qgspolymorphicrelation.py)
 ADD_PYTHON_TEST(PyQgsRelationManager test_qgsrelationmanager.py)
 ADD_PYTHON_TEST(PyQgsProjectRelationManager test_qgsprojectrelationmanager.py)
 ADD_PYTHON_TEST(PyQgsProviderSublayerTask test_qgsprovidersublayertask.py)
+ADD_PYTHON_TEST(PyQgsProviderUtils test_qgsproviderutils.py)
 ADD_PYTHON_TEST(PyQgsRenderContext test_qgsrendercontext.py)
 ADD_PYTHON_TEST(PyQgsRenderer test_qgsrenderer.py)
 ADD_PYTHON_TEST(PyQgsReport test_qgsreport.py)
diff --git a/tests/src/python/test_qgsproviderutils.py b/tests/src/python/test_qgsproviderutils.py
@@ -0,0 +1,53 @@
+# -*- coding: utf-8 -*-
+"""QGIS Unit tests for QgsProviderUtils.
+
+.. note:: 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.
+"""
+__author__ = 'Nyall Dawson'
+__date__ = '30/06/2021'
+__copyright__ = 'Copyright 2021, The QGIS Project'
+
+from qgis.core import (
+    Qgis,
+    QgsWkbTypes,
+    QgsProviderRegistry,
+    QgsProviderUtils
+)
+
+from qgis.testing import (
+    unittest,
+    start_app
+)
+from utilities import unitTestDataPath
+
+app = start_app()
+
+
+class TestQgsProviderUtils(unittest.TestCase):
+
+    def test_sublayerDetailsAreIncomplete(self):
+        """
+        Test sublayerDetailsAreIncomplete
+        """
+        uri = unitTestDataPath() + '/mixed_types.TAB'
+
+        # surface scan only
+        sublayers = QgsProviderRegistry.instance().querySublayers(uri)
+        self.assertEqual(len(sublayers), 1)
+        self.assertEqual(sublayers[0].wkbType(), QgsWkbTypes.Unknown)
+
+        # need to resolve geometry types for complete details about this uri!
+        self.assertTrue(QgsProviderUtils.sublayerDetailsAreIncomplete(sublayers))
+
+        # retry with retrieving geometry types
+        sublayers = QgsProviderRegistry.instance().querySublayers(uri, Qgis.SublayerQueryFlag.ResolveGeometryType)
+        # now we have all the details
+        self.assertEqual(len(sublayers), 3)
+        self.assertFalse(QgsProviderUtils.sublayerDetailsAreIncomplete(sublayers))
+
+
+if __name__ == '__main__':
+    unittest.main()
