Add test for DBManager's PostGIS connector and plugin

Only enabled when ENABLE_PGTEST is set
Includes test for dbname-less URI (#10600 and #16625 and #16626)

The test relies on default libpq accessed database containing
one raster table, but makes no effort to create such database yet.

python/plugins/db_manager/db_plugins/postgis/CMakeLists.txt

@@ -8,3 +8,10 @@ PLUGIN_INSTALL(db_manager db_plugins/postgis/icons ${ICON_FILES})
 
 ADD_SUBDIRECTORY(plugins)
 
+IF(ENABLE_TESTS)
+  INCLUDE(UsePythonTest)
+  IF (ENABLE_PGTEST)
+    ADD_PYTHON_TEST(dbmanager-postgis-connector connector_test.py)
+    ADD_PYTHON_TEST(dbmanager-postgis-plugin plugin_test.py)
+  ENDIF (ENABLE_PGTEST)
+ENDIF(ENABLE_TESTS)

python/plugins/db_manager/db_plugins/postgis/connector_test.py

@@ -0,0 +1,76 @@
+# -*- coding: utf-8 -*-
+
+"""
+***************************************************************************
+    connector_test.py
+    ---------------------
+    Date                 : May 2017
+    Copyright            : (C) 2017, Sandro Santilli
+    Email                : strk at kbt dot io
+***************************************************************************
+*                                                                         *
+*   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__ = 'Sandro Santilli'
+__date__ = 'May 2017'
+__copyright__ = '(C) 2017, Sandro Santilli'
+# This will get replaced with a git SHA1 when you do a git archive
+__revision__ = '$Format:%H$'
+
+import os
+import qgis
+from qgis.testing import start_app, unittest
+from qgis.core import QgsDataSourceUri
+from qgis.utils import iface
+
+start_app()
+
+from db_manager.db_plugins.postgis.connector import PostGisDBConnector
+
+
+class TestDBManagerPostgisConnector(unittest.TestCase):
+
+    #def setUpClass():
+
+    def _getUser(self, connector):
+        r = connector._execute(None, "SELECT USER")
+        val = connector._fetchone(r)[0]
+        connector._close_cursor(r)
+        return val
+
+    def _getDatabase(self, connector):
+        r = connector._execute(None, "SELECT current_database()")
+        val = connector._fetchone(r)[0]
+        connector._close_cursor(r)
+        return val
+
+    # See https://issues.qgis.org/issues/16625
+    # and https://issues.qgis.org/issues/10600
+    def test_dbnameLessURI(self):
+        c = PostGisDBConnector(QgsDataSourceUri())
+        self.assertIsInstance(c, PostGisDBConnector)
+        uri = c.uri()
+
+        # No username was passed, so we expect it to be taken
+        # from PGUSER or USER environment variables
+        expected_user = os.environ.get('PGUSER') or os.environ.get('USER')
+        actual_user = self._getUser(c)
+        self.assertEqual(actual_user, expected_user)
+
+        # No database was passed, so we expect it to be taken
+        # from PGDATABASE or expected user
+        expected_db = os.environ.get('PGDATABASE') or expected_user
+        actual_db = self._getDatabase(c)
+        self.assertEqual(actual_db, expected_db)
+
+    # TODO: add service-only test (requires a ~/.pg_service.conf file)
+
+
+if __name__ == '__main__':
+    unittest.main()

python/plugins/db_manager/db_plugins/postgis/plugin_test.py

@@ -0,0 +1,83 @@
+# -*- coding: utf-8 -*-
+
+"""
+***************************************************************************
+    plugin_test.py
+    ---------------------
+    Date                 : May 2017
+    Copyright            : (C) 2017, Sandro Santilli
+    Email                : strk at kbt dot io
+***************************************************************************
+*                                                                         *
+*   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__ = 'Sandro Santilli'
+__date__ = 'May 2017'
+__copyright__ = '(C) 2017, Sandro Santilli'
+# This will get replaced with a git SHA1 when you do a git archive
+__revision__ = '$Format:%H$'
+
+import os
+import re
+import qgis
+from qgis.testing import start_app, unittest
+from qgis.core import QgsDataSourceUri
+from qgis.utils import iface
+from qgis.PyQt.QtCore import QObject
+
+start_app()
+
+from db_manager.db_plugins.postgis.plugin import PostGisDBPlugin, PGRasterTable
+from db_manager.db_plugins.postgis.plugin import PGDatabase
+from db_manager.db_plugins.plugin import Table
+from db_manager.db_plugins.postgis.connector import PostGisDBConnector
+
+
+class TestDBManagerPostgisPlugin(unittest.TestCase):
+
+    # See https://issues.qgis.org/issues/16625
+    # and https://issues.qgis.org/issues/10600
+
+    def test_rasterTable(self):
+
+        #testdb = os.environ.get('QGIS_PGTEST_DB') or 'qgis_test'
+        #os.environ['PGDATABASE'] = testdb
+
+        obj = QObject() # needs to be kept alive
+        database = PGDatabase(obj, QgsDataSourceUri())
+        self.assertIsInstance(database, PGDatabase)
+
+        uri = database.uri()
+        self.assertEqual(uri.host(), '')
+        self.assertEqual(uri.username(), '')
+        expected_user = os.environ.get('PGUSER') or os.environ.get('USER')
+        expected_dbname = os.environ.get('PGDATABASE') or expected_user
+        self.assertEqual(uri.database(), expected_dbname)
+
+        tables = database.tables()
+        raster_tables_count = 0
+        for tab in tables:
+            if tab.type == Table.RasterType:
+                raster_tables_count += 1
+                gdalUri = tab.gdalUri()
+                m = re.search(' dbname=([^ ]*) ', gdalUri)
+                self.assertTrue(m)
+                actual_dbname = m.group(1)
+                self.assertEqual(actual_dbname, expected_dbname)
+            #print(tab.type)
+            #print(tab.quotedName())
+            #print(tab)
+
+        # We need to make sure a database is created with at
+        # least one raster table !
+        self.assertEqual(raster_tables_count, 1)
+
+
+if __name__ == '__main__':
+    unittest.main()