improvements towards import rdf layer

dialogs/tool/importrdflayerdialog.py

@@ -6,6 +6,7 @@
 from qgis.PyQt.QtCore import QRegExp
 from qgis.PyQt.QtGui import QRegExpValidator
 from ...tasks.processing.extractnamespacetask import ExtractNamespaceTask
+from ...tasks.processing.extractlayertask import ExtractLayerTask
 
 from ...util.ui.uiutils import UIUtils
 from ...tasks.processing.convertcrstask import ConvertCRSTask
@@ -36,9 +37,14 @@ def __init__(self, triplestoreconf={}, maindlg=None, parent=None, title="Import
         self.dlg = parent
         self.maindlg = maindlg
         self.inputRDFFileWidget.fileChanged.connect(self.extractClasses)
+        self.addSelectedLayersButton.clicked.connect(self.extractLayers)
 
 
     def extractClasses(self,filename):
         self.tsk=ExtractNamespaceTask("Extracting namespaces from "+str(filename),filename,None,self.layerSelectBox,self.prefixes,None)
         QgsApplication.taskManager().addTask(self.tsk)
 
+    def extractLayers(self):
+        self.task=ExtractLayerTask("Extracting layers from "+str(self.inputRDFFileWidget.filePath()),self.inputRDFFileWidget.filePath(),self.layerSelectBox.checkedItemsData(),self.triplestoreconf,self.prefixes,None)
+        QgsApplication.taskManager().addTask(self.task)
+

dialogs/ui/importrdflayer.ui

@@ -19,7 +19,7 @@
   </property>
   <layout class="QGridLayout" name="gridLayout">
    <item row="5" column="0" colspan="2">
-    <widget class="QPushButton" name="convertToRDFButton">
+    <widget class="QPushButton" name="addSelectedLayersButton">
      <property name="text">
       <string>Add Selected Layers</string>
      </property>

tasks/processing/extractlayertask.py

@@ -5,59 +5,68 @@
 from qgis.PyQt.QtWidgets import QMessageBox
 from rdflib import Graph, URIRef, RDF
 from ...util.sparqlutils import SPARQLUtils
+from ...util.layerutils import LayerUtils
+from qgis.core import QgsProject, QgsVectorLayer
+import json
 
 MESSAGE_CATEGORY = 'ExtractLayerTask'
 
 class ExtractLayerTask(QgsTask):
 
-    def __init__(self, description, graphname,toextract,triplestoreconf,resultfolder=".",prefixes=None, progress=None):
+    def __init__(self, description, graphname,toextract,triplestoreconf,prefixes=None, progress=None):
         super().__init__(description, QgsTask.CanCancel)
         self.exception = None
         self.progress = progress
         self.graphname = graphname
-        self.prefixes=resultfolder
+        self.prefixes=prefixes
         self.triplestoreconf=triplestoreconf
         self.toextract=toextract
+        self.layers=[]
+        QgsMessageLog.logMessage(str(self.toextract),
+                                 MESSAGE_CATEGORY, Qgis.Info)
+        QgsMessageLog.logMessage(str(self.graphname),
+                                 MESSAGE_CATEGORY, Qgis.Info)
 
 
     def run(self):
-        def run(self):
-            try:
-                g = Graph()
-                g.parse(self.graphname, format="ttl")
-                namespacetosub = {}
-                for toex in self.toextract:
-                    for sub in g.subjects(None, RDF.type, URIRef(toex)):
-                        for predobj in sub.predicate_objects():
-
-                        ns = SPARQLUtils.instanceToNS(sub)
-                        if self.prefixes is not None and "reversed" in self.prefixes and ns in self.prefixes["reversed"]:
-                            self.recognizedns.add(ns)
-                        else:
-                            self.namespaces.add(ns)
-                        if ns not in namespacetosub:
-                            namespacetosub[ns] = set()
-                        namespacetosub[ns].add(sub)
-                res = self.identifyDataClasses(g, namespacetosub)
-                self.nstodataclass = res["nsd"]
-                self.classset = res["clsset"]
-                return True
-            except Exception as e:
-                self.exception = e
-                return False
+        #try:
+        g = Graph()
+        g.parse(self.graphname, format="ttl")
+        for toex in self.toextract:
+            if "owl" not in str(toex) and "rdf" not in str(toex):
+                QgsMessageLog.logMessage(str(toex),
+                                         MESSAGE_CATEGORY, Qgis.Info)
+                layergraph = Graph()
+                for sub in g.subjects(RDF.type, URIRef(toex),True):
+                    QgsMessageLog.logMessage(str(sub),
+                                             MESSAGE_CATEGORY, Qgis.Info)
+                    for trip in g.triples((sub,None,None)):
+                        layergraph.add(trip)
+                res=LayerUtils.subGraphToLayer(layergraph,False, self.triplestoreconf, True, False)
+                #QgsMessageLog.logMessage(str(res[0]), MESSAGE_CATEGORY, Qgis.Info)
+                self.layers.append(QgsVectorLayer(json.dumps(res[0], sort_keys=True), "unicorn_" + str(SPARQLUtils.labelFromURI(str(toex))), "ogr"))
+        return True
+        #except Exception as e:
+        #    self.exception = e
+        #    QgsMessageLog.logMessage(str(e),
+        #                             MESSAGE_CATEGORY, Qgis.Info)
+        #    return False
         return True
 
     def finished(self, result):
-        self.progress.close()
+        #self.progress.close()
         if result:
-            iface.messageBar().pushMessage("Exported layer successfully to " + str(self.filename[0]) + "!", "OK",
-                                           level=Qgis.Success)
+            QgsMessageLog.logMessage(str(len(self.layers)),
+                                     MESSAGE_CATEGORY, Qgis.Info)
+            for layer in self.layers:
+                QgsProject.instance().addMapLayer(layer)
+            iface.messageBar().pushMessage("Successfully extracted layers from "+str(self.graphname)+"!", "OK",level=Qgis.Success)
             msgBox = QMessageBox()
-            msgBox.setText("Layer converted to and saved as "+str(self.filename[0]))
+            msgBox.setText("Layer extracted from "+str(self.graphname))
             msgBox.exec()
         else:
             msgBox = QMessageBox()
-            msgBox.setText("An error occurred while converting the layer converted to "+str(self.filename[0]))
+            msgBox.setText("An error occurred while extracting layers from  "+str(self.graphname))
             msgBox.exec()
 
 

util/export/layer/layerexporter.py

@@ -87,7 +87,6 @@ def layerToTTLString(layer, prefixes, vocab="GeoSPARQL", literaltype=["WKT"], ur
         #                         MESSAGE_CATEGORY, Qgis.Info)
         # QgsMessageLog.logMessage("FIELDNAMES: "+str(vocab),
         #                         MESSAGE_CATEGORY, Qgis.Info)
-        ttlstring = set()
         graph=Graph()
         first = 0
         if exportNameSpace is None or exportNameSpace == "":
@@ -116,7 +115,7 @@ def layerToTTLString(layer, prefixes, vocab="GeoSPARQL", literaltype=["WKT"], ur
                                                                                           "_")),URIRef("http://www.opengis.net/ont/crs/asProj"),Literal(str(
             layercrs.toProj4()).replace("\"", "\\\""),datatype="http://www.opengis.net/ont/crs/proj4Literal")))
         ccrs = ConvertCRS()
-        ttlstring = ccrs.convertCRSFromWKTStringSet(layercrs.toWkt(), ttlstring)
+        graph = ccrs.convertCRSFromWKTStringSet(layercrs.toWkt(), graph)
         init = True
         for f in layer.getFeatures():
             geom = f.geometry()
@@ -133,7 +132,7 @@ def layerToTTLString(layer, prefixes, vocab="GeoSPARQL", literaltype=["WKT"], ur
                     graph.add((URIRef(str(curclassid)), RDFS.type, OWL.Class))
             else:
                 curclassid = f["http://www.w3.org/1999/02/22-rdf-syntax-ns#type"]
-            graph = LayerUtils.exportGeometryType(curid, geom, vocab, literaltype, init, ttlstring)
+            graph = LayerUtils.exportGeometryType(curid, geom, vocab, literaltype, init, graph)
             if init:
                 init = False
             fieldcounter = -1
@@ -229,7 +228,7 @@ def layerToTTLString(layer, prefixes, vocab="GeoSPARQL", literaltype=["WKT"], ur
                         graph.add((URIRef(prop), RDFS.range, XSD.string))
             if first < 10:
                 first = first + 1
-        return ccrs.ttlhead + "".join(ttlstring)
+        return graph
 
 
     @staticmethod