Merge pull request #1375 from nyalldawson/processing_postgis2

jef-n · jef-n · commit e2c2575485f2 · 2014-05-21T09:02:56.000+02:00
Some postgresql provider and PostGIS-related processing improvements and fixes (v2)
diff --git a/python/plugins/processing/algs/admintools/ImportIntoPostGIS.py b/python/plugins/processing/algs/admintools/ImportIntoPostGIS.py
@@ -36,6 +36,7 @@
 from processing.parameters.ParameterVector import ParameterVector
 from processing.parameters.ParameterString import ParameterString
 from processing.parameters.ParameterSelection import ParameterSelection
+from processing.parameters.ParameterTableField import ParameterTableField
 from processing.tools import dataobjects
 import postgis_utils
 
@@ -50,6 +51,8 @@ class ImportIntoPostGIS(GeoAlgorithm):
     CREATEINDEX = 'CREATEINDEX'
     GEOMETRY_COLUMN = 'GEOMETRY_COLUMN'
     LOWERCASE_NAMES = 'LOWERCASE_NAMES'
+    DROP_STRING_LENGTH = 'DROP_STRING_LENGTH'
+    PRIMARY_KEY = 'PRIMARY_KEY'
 
     def getIcon(self):
         return QIcon(os.path.dirname(__file__) + '/../../images/postgis.png')
@@ -60,6 +63,8 @@ def processAlgorithm(self, progress):
         overwrite = self.getParameterValue(self.OVERWRITE)
         createIndex = self.getParameterValue(self.CREATEINDEX)
         convertLowerCase = self.getParameterValue(self.LOWERCASE_NAMES)
+        dropStringLength = self.getParameterValue(self.DROP_STRING_LENGTH)
+        primaryKeyField = self.getParameterValue(self.PRIMARY_KEY)
         settings = QSettings()
         mySettings = '/PostgreSQL/connections/' + connection
         try:
@@ -87,15 +92,22 @@ def processAlgorithm(self, progress):
         if not geomColumn:
             geomColumn = 'the_geom'
 
-        uri = QgsDataSourceURI()
-        uri.setConnection(host, str(port), database, username, password)
-        uri.setDataSource(schema, table, geomColumn, '')
-
         options = {}
         if overwrite:
             options['overwrite'] = True
         if convertLowerCase:
             options['lowercaseFieldNames'] = True
+            geomColumn = geomColumn.lower()
+        if dropStringLength:
+            options['dropStringConstraints'] = True
+            
+        uri = QgsDataSourceURI()
+        uri.setConnection(host, str(port), database, username, password)
+        if primaryKeyField:
+            uri.setDataSource(schema, table, geomColumn, '', primaryKeyField)
+        else:
+            uri.setDataSource(schema, table, geomColumn, '')
+            
         layerUri = self.getParameterValue(self.INPUT)
         layer = dataobjects.getObjectFromUri(layerUri)
         (ret, errMsg) = QgsVectorLayerImport.importLayer(
@@ -133,10 +145,14 @@ def defineCharacteristics(self):
         self.addParameter(ParameterString(self.SCHEMA, 'Schema (schema name)'))
         self.addParameter(ParameterString(self.TABLENAME, 'Table to import to'
                           ))
+        self.addParameter(ParameterTableField(self.PRIMARY_KEY, 'Primary key field',
+                          self.INPUT, optional=True))
         self.addParameter(ParameterString(self.GEOMETRY_COLUMN, 'Geometry column', 'the_geom'
                           ))
         self.addParameter(ParameterBoolean(self.OVERWRITE, 'Overwrite', True))
         self.addParameter(ParameterBoolean(self.CREATEINDEX,
                           'Create spatial index', True))
         self.addParameter(ParameterBoolean(self.LOWERCASE_NAMES,
                           'Convert field names to lowercase', False))
+        self.addParameter(ParameterBoolean(self.DROP_STRING_LENGTH,
+                          'Drop length constraints on character fields', False))
diff --git a/src/providers/postgres/qgspostgresprovider.cpp b/src/providers/postgres/qgspostgresprovider.cpp
@@ -2767,9 +2767,17 @@ bool QgsPostgresProvider::getGeometryDetails()
   return mValid;
 }
 
-bool QgsPostgresProvider::convertField( QgsField &field )
+bool QgsPostgresProvider::convertField( QgsField &field , const QMap<QString, QVariant>* options )
 {
-  QString fieldType = "varchar"; //default to string
+  //determine field type to use for strings
+  QString stringFieldType = "varchar";
+  if ( options->contains( "dropStringConstraints" ) && options->value( "dropStringConstraints" ).toBool() )
+  {
+    //drop string length constraints by using PostgreSQL text type for strings
+    stringFieldType = "text";
+  }
+
+  QString fieldType = stringFieldType; //default to string
   int fieldSize = field.length();
   int fieldPrec = field.precision();
   switch ( field.type() )
@@ -2788,7 +2796,7 @@ bool QgsPostgresProvider::convertField( QgsField &field )
       break;
 
     case QVariant::String:
-      fieldType = "varchar";
+      fieldType = stringFieldType;
       fieldPrec = -1;
       break;
 
@@ -2900,7 +2908,7 @@ QgsVectorLayerImport::ImportError QgsPostgresProvider::createEmptyLayer(
       {
         // found, get the field type
         QgsField fld = fields[fldIdx];
-        if ( convertField( fld ) )
+        if ( convertField( fld, options ) )
         {
           primaryKeyType = fld.typeName();
         }
@@ -2953,6 +2961,13 @@ QgsVectorLayerImport::ImportError QgsPostgresProvider::createEmptyLayer(
         throw PGException( result );
     }
 
+    if ( options->contains( "lowercaseFieldNames" ) && options->value( "lowercaseFieldNames" ).toBool() )
+    {
+      //convert primary key name to lowercase
+      //this must happen after determining the field type of the primary key
+      primaryKey = primaryKey.toLower();
+    }
+
     sql = QString( "CREATE TABLE %1(%2 %3 PRIMARY KEY)" )
           .arg( schemaTableName )
           .arg( quotedIdentifier( primaryKey ) )
@@ -3032,14 +3047,11 @@ QgsVectorLayerImport::ImportError QgsPostgresProvider::createEmptyLayer(
     for ( int fldIdx = 0; fldIdx < fields.count(); ++fldIdx )
     {
       QgsField fld = fields[fldIdx];
-      if ( fld.name() == primaryKey )
-      {
-        oldToNewAttrIdxMap->insert( fldIdx, 0 );
-        continue;
-      }
 
       if ( fld.name() == geometryColumn )
       {
+        //the "lowercaseFieldNames" option does not affect the name of the geometry column, so we perform
+        //this test before converting the field name to lowercase
         QgsDebugMsg( "Found a field with the same name of the geometry column. Skip it!" );
         continue;
       }
@@ -3050,7 +3062,13 @@ QgsVectorLayerImport::ImportError QgsPostgresProvider::createEmptyLayer(
         fld.setName( fld.name().toLower() );
       }
 
-      if ( !convertField( fld ) )
+      if ( fld.name() == primaryKey )
+      {
+        oldToNewAttrIdxMap->insert( fldIdx, 0 );
+        continue;
+      }
+
+      if ( !convertField( fld, options ) )
       {
         if ( errorMessage )
           *errorMessage = QObject::tr( "Unsupported type for field %1" ).arg( fld.name() );
diff --git a/src/providers/postgres/qgspostgresprovider.h b/src/providers/postgres/qgspostgresprovider.h
@@ -47,7 +47,12 @@ class QgsPostgresProvider : public QgsVectorDataProvider
 
   public:
 
-    /** Import a vector layer into the database */
+    /** Import a vector layer into the database
+     * @param options options for provider, specified via a map of option name
+     * to value. Valid options are lowercaseFieldNames (set to true to convert
+     * field names to lowercase), dropStringConstraints (set to true to remove
+     * length constraints on character fields).
+    */
     static QgsVectorLayerImport::ImportError createEmptyLayer(
       const QString& uri,
       const QgsFields &fields,
@@ -324,7 +329,7 @@ class QgsPostgresProvider : public QgsVectorDataProvider
     bool loadFields();
 
     /** convert a QgsField to work with PG */
-    static bool convertField( QgsField &field );
+    static bool convertField( QgsField &field, const QMap<QString, QVariant> *options = 0 );
 
     /**Parses the enum_range of an attribute and inserts the possible values into a stringlist
     @param enumValues the stringlist where the values are appended
