Port hub lines algorithm to new API

Improvements: - transparent reprojection to match hub/spoke CRS - keep all attributes from matched hub/spoke features - don't break after matching one hub point to spoke - instead join ALL hub/spoke points with matching id values
2025-02-25 00:58:06 -05:00 · 2017-08-03 19:49:50 +10:00 · 2017-08-03 19:49:50 +10:00 · b4b39996d2
commit b4b39996d2
parent e0354456e3
8 changed files with 306 additions and 50 deletions
--- a/python/plugins/processing/algs/help/qgis.yaml
+++ b/python/plugins/processing/algs/help/qgis.yaml
@ -242,7 +242,9 @@ qgis:generatepointspixelcentroidsinsidepolygons:


 qgis:hublines:
+  This algorithm creates hub and spoke diagrams with lines drawn from points on the Spoke Point layer to matching points in the Hub Point layer.

+  Determination of which hub goes with each point is based on a match between the Hub ID field on the hub points and the Spoke ID field on the spoke points.

 qgis:hypsometriccurves: >
  This algorithm computes hypsometric curves  for an input Digital Elevation Model. Curves are produced as table files in an output folder specified by the user.
--- a/python/plugins/processing/algs/qgis/HubLines.py
+++ b/python/plugins/processing/algs/qgis/HubLines.py
@ -31,15 +31,15 @@ from qgis.core import (QgsFeature,
                       QgsGeometry,
                       QgsPointXY,
                       QgsWkbTypes,
-                       QgsApplication,
-                       QgsProcessingUtils)
+                       QgsFeatureRequest,
+                       QgsProcessing,
+                       QgsProcessingParameterFeatureSource,
+                       QgsProcessingParameterField,
+                       QgsProcessingParameterFeatureSink,
+                       QgsProcessingException,
+                       QgsExpression)
 from processing.algs.qgis.QgisAlgorithm import QgisAlgorithm
-from processing.core.GeoAlgorithmExecutionException import GeoAlgorithmExecutionException
-from processing.core.parameters import ParameterVector
-from processing.core.parameters import ParameterTableField
-from processing.core.outputs import OutputVector
-
-from processing.tools import dataobjects
+from processing.tools import vector


 class HubLines(QgisAlgorithm):
@ -55,17 +55,21 @@ class HubLines(QgisAlgorithm):
    def __init__(self):
        super().__init__()

-    def initAlgorithm(self, config=None):
-        self.addParameter(ParameterVector(self.HUBS,
-                                          self.tr('Hub layer')))
-        self.addParameter(ParameterTableField(self.HUB_FIELD,
-                                              self.tr('Hub ID field'), self.HUBS))
-        self.addParameter(ParameterVector(self.SPOKES,
-                                          self.tr('Spoke layer')))
-        self.addParameter(ParameterTableField(self.SPOKE_FIELD,
-                                              self.tr('Spoke ID field'), self.SPOKES))
+    def tags(self):
+        return self.tr('join,points,lines,connect,hub,spoke').split(',')

-        self.addOutput(OutputVector(self.OUTPUT, self.tr('Hub lines'), datatype=[dataobjects.TYPE_VECTOR_LINE]))
+    def initAlgorithm(self, config=None):
+
+        self.addParameter(QgsProcessingParameterFeatureSource(self.HUBS,
+                                                              self.tr('Hub layer')))
+        self.addParameter(QgsProcessingParameterField(self.HUB_FIELD,
+                                                      self.tr('Hub ID field'), parentLayerParameterName=self.HUBS))
+        self.addParameter(QgsProcessingParameterFeatureSource(self.SPOKES,
+                                                              self.tr('Spoke layer')))
+        self.addParameter(QgsProcessingParameterField(self.SPOKE_FIELD,
+                                                      self.tr('Spoke ID field'), parentLayerParameterName=self.SPOKES))
+
+        self.addParameter(QgsProcessingParameterFeatureSink(self.OUTPUT, self.tr('Hub lines'), QgsProcessing.TypeVectorLine))

    def name(self):
        return 'hublines'
@ -74,44 +78,61 @@ class HubLines(QgisAlgorithm):
        return self.tr('Hub lines')

    def processAlgorithm(self, parameters, context, feedback):
-        layerHub = QgsProcessingUtils.mapLayerFromString(self.getParameterValue(self.HUBS), context)
-        layerSpoke = QgsProcessingUtils.mapLayerFromString(self.getParameterValue(self.SPOKES), context)
-
-        fieldHub = self.getParameterValue(self.HUB_FIELD)
-        fieldSpoke = self.getParameterValue(self.SPOKE_FIELD)
-
-        if layerHub.source() == layerSpoke.source():
-            raise GeoAlgorithmExecutionException(
+        if parameters[self.SPOKES] == parameters[self.HUBS]:
+            raise QgsProcessingException(
                self.tr('Same layer given for both hubs and spokes'))

-        writer = self.getOutputFromName(self.OUTPUT).getVectorWriter(layerSpoke.fields(), QgsWkbTypes.LineString,
-                                                                     layerSpoke.crs(), context)
+        hub_source = self.parameterAsSource(parameters, self.HUBS, context)
+        spoke_source = self.parameterAsSource(parameters, self.SPOKES, context)
+        field_hub = self.parameterAsString(parameters, self.HUB_FIELD, context)
+        field_hub_index = hub_source.fields().lookupField(field_hub)
+        field_spoke = self.parameterAsString(parameters, self.SPOKE_FIELD, context)
+        field_spoke_index = hub_source.fields().lookupField(field_spoke)

-        spokes = QgsProcessingUtils.getFeatures(layerSpoke, context)
-        hubs = QgsProcessingUtils.getFeatures(layerHub, context)
-        total = 100.0 / layerSpoke.featureCount() if layerSpoke.featureCount() else 0
+        fields = vector.combineFields(hub_source.fields(), spoke_source.fields())

-        for current, spokepoint in enumerate(spokes):
-            p = spokepoint.geometry().boundingBox().center()
-            spokeX = p.x()
-            spokeY = p.y()
-            spokeId = str(spokepoint[fieldSpoke])
+        (sink, dest_id) = self.parameterAsSink(parameters, self.OUTPUT, context,
+                                               fields, QgsWkbTypes.LineString, hub_source.sourceCrs())

-            for hubpoint in hubs:
-                hubId = str(hubpoint[fieldHub])
-                if hubId == spokeId:
-                    p = hubpoint.geometry().boundingBox().center()
-                    hubX = p.x()
-                    hubY = p.y()
+        hubs = hub_source.getFeatures()
+        total = 100.0 / hub_source.featureCount() if hub_source.featureCount() else 0
+
+        matching_field_types = hub_source.fields().at(field_hub_index).type() == spoke_source.fields().at(field_spoke_index).type()
+
+        for current, hub_point in enumerate(hubs):
+            if feedback.isCanceled():
+                break
+
+            if not hub_point.hasGeometry():
+                continue
+
+            p = hub_point.geometry().boundingBox().center()
+            hub_x = p.x()
+            hub_y = p.y()
+            hub_id = str(hub_point[field_hub])
+            hub_attributes = hub_point.attributes()
+
+            request = QgsFeatureRequest().setDestinationCrs(hub_source.sourceCrs())
+            if matching_field_types:
+                request.setFilterExpression(QgsExpression.createFieldEqualityExpression(field_spoke, hub_attributes[field_hub_index]))
+
+            spokes = spoke_source.getFeatures()
+            for spoke_point in spokes:
+                if feedback.isCanceled():
+                    break
+
+                spoke_id = str(spoke_point[field_spoke])
+                if hub_id == spoke_id:
+                    p = spoke_point.geometry().boundingBox().center()
+                    spoke_x = p.x()
+                    spoke_y = p.y()

                    f = QgsFeature()
-                    f.setAttributes(spokepoint.attributes())
+                    f.setAttributes(hub_attributes + spoke_point.attributes())
                    f.setGeometry(QgsGeometry.fromPolyline(
-                        [QgsPointXY(spokeX, spokeY), QgsPointXY(hubX, hubY)]))
-                    writer.addFeature(f, QgsFeatureSink.FastInsert)
-
-                    break
+                        [QgsPointXY(hub_x, hub_y), QgsPointXY(spoke_x, spoke_y)]))
+                    sink.addFeature(f, QgsFeatureSink.FastInsert)

            feedback.setProgress(int(current * total))

-        del writer
+        return {self.OUTPUT: dest_id}
--- a/python/plugins/processing/algs/qgis/QGISAlgorithmProvider.py
+++ b/python/plugins/processing/algs/qgis/QGISAlgorithmProvider.py
@ -77,6 +77,7 @@ from .Heatmap import Heatmap
 from .Hillshade import Hillshade
 from .HubDistanceLines import HubDistanceLines
 from .HubDistancePoints import HubDistancePoints
+from .HubLines import HubLines
 from .ImportIntoPostGIS import ImportIntoPostGIS
 from .ImportIntoSpatialite import ImportIntoSpatialite
 from .Intersection import Intersection
@ -143,7 +144,6 @@ from .ZonalStatistics import ZonalStatistics
 # from .ExtractByLocation import ExtractByLocation
 # from .SelectByLocation import SelectByLocation
 # from .SpatialJoin import SpatialJoin
-# from .HubLines import HubLines
 # from .GeometryConvert import GeometryConvert
 # from .StatisticsByCategories import StatisticsByCategories
 # from .FieldsCalculator import FieldsCalculator
@ -188,7 +188,6 @@ class QGISAlgorithmProvider(QgsProcessingProvider):
        #         SelectByLocation(),
        #         ExtractByLocation(),
        #         SpatialJoin(),
-        #         HubLines(),
        #         GeometryConvert(), FieldsCalculator(),
        #          JoinAttributes(),
        #         FieldsPyculator(),
@ -246,6 +245,7 @@ class QGISAlgorithmProvider(QgsProcessingProvider):
                Hillshade(),
                HubDistanceLines(),
                HubDistancePoints(),
+                HubLines(),
                ImportIntoPostGIS(),
                ImportIntoSpatialite(),
                Intersection(),
--- a/python/plugins/processing/tests/testdata/custom/spoke_points.gfs
+++ b/python/plugins/processing/tests/testdata/custom/spoke_points.gfs
@ -0,0 +1,27 @@
+<GMLFeatureClassList>
+  <GMLFeatureClass>
+    <Name>spoke_points</Name>
+    <ElementPath>spoke_points</ElementPath>
+    <!--POINT-->
+    <GeometryType>1</GeometryType>
+    <SRSName>EPSG:4326</SRSName>
+    <DatasetSpecificInfo>
+      <FeatureCount>7</FeatureCount>
+      <ExtentXMin>1.27875</ExtentXMin>
+      <ExtentXMax>6.82625</ExtentXMax>
+      <ExtentYMin>-4.16750</ExtentYMin>
+      <ExtentYMax>3.88250</ExtentYMax>
+    </DatasetSpecificInfo>
+    <PropertyDefn>
+      <Name>id</Name>
+      <ElementPath>id</ElementPath>
+      <Type>Integer</Type>
+    </PropertyDefn>
+    <PropertyDefn>
+      <Name>name</Name>
+      <ElementPath>name</ElementPath>
+      <Type>String</Type>
+      <Width>8</Width>
+    </PropertyDefn>
+  </GMLFeatureClass>
+</GMLFeatureClassList>
--- a/python/plugins/processing/tests/testdata/custom/spoke_points.gml
+++ b/python/plugins/processing/tests/testdata/custom/spoke_points.gml
@ -0,0 +1,63 @@
+<?xml version="1.0" encoding="utf-8" ?>
+<ogr:FeatureCollection
+     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+     xsi:schemaLocation="http://ogr.maptools.org/ spoke_points.xsd"
+     xmlns:ogr="http://ogr.maptools.org/"
+     xmlns:gml="http://www.opengis.net/gml">
+  <gml:boundedBy>
+    <gml:Box>
+      <gml:coord><gml:X>1.27875</gml:X><gml:Y>-4.1675</gml:Y></gml:coord>
+      <gml:coord><gml:X>6.826249999999999</gml:X><gml:Y>3.882499999999999</gml:Y></gml:coord>
+    </gml:Box>
+  </gml:boundedBy>
+                                                                                                                    
+  <gml:featureMember>
+    <ogr:spoke_points fid="spoke_points.0">
+      <ogr:geometryProperty><gml:Point srsName="EPSG:4326"><gml:coordinates>5.07625,-2.1725</gml:coordinates></gml:Point></ogr:geometryProperty>
+      <ogr:id>1</ogr:id>
+      <ogr:name>point 1</ogr:name>
+    </ogr:spoke_points>
+  </gml:featureMember>
+  <gml:featureMember>
+    <ogr:spoke_points fid="spoke_points.1">
+      <ogr:geometryProperty><gml:Point srsName="EPSG:4326"><gml:coordinates>5.82,3.8825</gml:coordinates></gml:Point></ogr:geometryProperty>
+      <ogr:id>2</ogr:id>
+      <ogr:name>point 2</ogr:name>
+    </ogr:spoke_points>
+  </gml:featureMember>
+  <gml:featureMember>
+    <ogr:spoke_points fid="spoke_points.2">
+      <ogr:geometryProperty><gml:Point srsName="EPSG:4326"><gml:coordinates>1.62,1.4675</gml:coordinates></gml:Point></ogr:geometryProperty>
+      <ogr:id>3</ogr:id>
+      <ogr:name>point 3</ogr:name>
+    </ogr:spoke_points>
+  </gml:featureMember>
+  <gml:featureMember>
+    <ogr:spoke_points fid="spoke_points.3">
+      <ogr:geometryProperty><gml:Point srsName="EPSG:4326"><gml:coordinates>6.68625,1.23125</gml:coordinates></gml:Point></ogr:geometryProperty>
+      <ogr:id>4</ogr:id>
+      <ogr:name>point 4</ogr:name>
+    </ogr:spoke_points>
+  </gml:featureMember>
+  <gml:featureMember>
+    <ogr:spoke_points fid="spoke_points.4">
+      <ogr:geometryProperty><gml:Point srsName="EPSG:4326"><gml:coordinates>1.27875,-3.66875</gml:coordinates></gml:Point></ogr:geometryProperty>
+      <ogr:id>4</ogr:id>
+      <ogr:name>point 4a</ogr:name>
+    </ogr:spoke_points>
+  </gml:featureMember>
+  <gml:featureMember>
+    <ogr:spoke_points fid="spoke_points.5">
+      <ogr:geometryProperty><gml:Point srsName="EPSG:4326"><gml:coordinates>3.81625,-4.1675</gml:coordinates></gml:Point></ogr:geometryProperty>
+      <ogr:id>4</ogr:id>
+      <ogr:name>point 4b</ogr:name>
+    </ogr:spoke_points>
+  </gml:featureMember>
+  <gml:featureMember>
+    <ogr:spoke_points fid="spoke_points.6">
+      <ogr:geometryProperty><gml:Point srsName="EPSG:4326"><gml:coordinates>6.82625,-2.79375</gml:coordinates></gml:Point></ogr:geometryProperty>
+      <ogr:id>8</ogr:id>
+      <ogr:name>point 8</ogr:name>
+    </ogr:spoke_points>
+  </gml:featureMember>
+</ogr:FeatureCollection>
--- a/python/plugins/processing/tests/testdata/expected/hub_lines.gfs
+++ b/python/plugins/processing/tests/testdata/expected/hub_lines.gfs
@ -0,0 +1,43 @@
+<GMLFeatureClassList>
+  <GMLFeatureClass>
+    <Name>hub_lines</Name>
+    <ElementPath>hub_lines</ElementPath>
+    <!--LINESTRING-->
+    <GeometryType>2</GeometryType>
+    <SRSName>EPSG:4326</SRSName>
+    <DatasetSpecificInfo>
+      <FeatureCount>7</FeatureCount>
+      <ExtentXMin>1.00000</ExtentXMin>
+      <ExtentXMax>7.00000</ExtentXMax>
+      <ExtentYMin>-4.16750</ExtentYMin>
+      <ExtentYMax>3.88250</ExtentYMax>
+    </DatasetSpecificInfo>
+    <PropertyDefn>
+      <Name>id</Name>
+      <ElementPath>id</ElementPath>
+      <Type>Integer</Type>
+    </PropertyDefn>
+    <PropertyDefn>
+      <Name>id2</Name>
+      <ElementPath>id2</ElementPath>
+      <Type>Integer</Type>
+    </PropertyDefn>
+    <PropertyDefn>
+      <Name>fid_2</Name>
+      <ElementPath>fid_2</ElementPath>
+      <Type>String</Type>
+      <Width>14</Width>
+    </PropertyDefn>
+    <PropertyDefn>
+      <Name>id_2</Name>
+      <ElementPath>id_2</ElementPath>
+      <Type>Integer</Type>
+    </PropertyDefn>
+    <PropertyDefn>
+      <Name>name</Name>
+      <ElementPath>name</ElementPath>
+      <Type>String</Type>
+      <Width>8</Width>
+    </PropertyDefn>
+  </GMLFeatureClass>
+</GMLFeatureClassList>
--- a/python/plugins/processing/tests/testdata/expected/hub_lines.gml
+++ b/python/plugins/processing/tests/testdata/expected/hub_lines.gml
@ -0,0 +1,84 @@
+<?xml version="1.0" encoding="utf-8" ?>
+<ogr:FeatureCollection
+     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+     xsi:schemaLocation=""
+     xmlns:ogr="http://ogr.maptools.org/"
+     xmlns:gml="http://www.opengis.net/gml">
+  <gml:boundedBy>
+    <gml:Box>
+      <gml:coord><gml:X>1</gml:X><gml:Y>-4.1675</gml:Y></gml:coord>
+      <gml:coord><gml:X>7</gml:X><gml:Y>3.8825</gml:Y></gml:coord>
+    </gml:Box>
+  </gml:boundedBy>
+                                                                                                                                                     
+  <gml:featureMember>
+    <ogr:hub_lines fid="points.0">
+      <ogr:geometryProperty><gml:LineString srsName="EPSG:4326"><gml:coordinates>1,1 5.07625,-2.1725</gml:coordinates></gml:LineString></ogr:geometryProperty>
+      <ogr:id>1</ogr:id>
+      <ogr:id2>2</ogr:id2>
+      <ogr:fid_2>spoke_points.0</ogr:fid_2>
+      <ogr:id_2>1</ogr:id_2>
+      <ogr:name>point 1</ogr:name>
+    </ogr:hub_lines>
+  </gml:featureMember>
+  <gml:featureMember>
+    <ogr:hub_lines fid="points.1">
+      <ogr:geometryProperty><gml:LineString srsName="EPSG:4326"><gml:coordinates>3,3 5.82,3.8825</gml:coordinates></gml:LineString></ogr:geometryProperty>
+      <ogr:id>2</ogr:id>
+      <ogr:id2>1</ogr:id2>
+      <ogr:fid_2>spoke_points.1</ogr:fid_2>
+      <ogr:id_2>2</ogr:id_2>
+      <ogr:name>point 2</ogr:name>
+    </ogr:hub_lines>
+  </gml:featureMember>
+  <gml:featureMember>
+    <ogr:hub_lines fid="points.2">
+      <ogr:geometryProperty><gml:LineString srsName="EPSG:4326"><gml:coordinates>2,2 1.62,1.4675</gml:coordinates></gml:LineString></ogr:geometryProperty>
+      <ogr:id>3</ogr:id>
+      <ogr:id2>0</ogr:id2>
+      <ogr:fid_2>spoke_points.2</ogr:fid_2>
+      <ogr:id_2>3</ogr:id_2>
+      <ogr:name>point 3</ogr:name>
+    </ogr:hub_lines>
+  </gml:featureMember>
+  <gml:featureMember>
+    <ogr:hub_lines fid="points.3">
+      <ogr:geometryProperty><gml:LineString srsName="EPSG:4326"><gml:coordinates>5,2 6.68625,1.23125</gml:coordinates></gml:LineString></ogr:geometryProperty>
+      <ogr:id>4</ogr:id>
+      <ogr:id2>2</ogr:id2>
+      <ogr:fid_2>spoke_points.3</ogr:fid_2>
+      <ogr:id_2>4</ogr:id_2>
+      <ogr:name>point 4</ogr:name>
+    </ogr:hub_lines>
+  </gml:featureMember>
+  <gml:featureMember>
+    <ogr:hub_lines fid="points.3">
+      <ogr:geometryProperty><gml:LineString srsName="EPSG:4326"><gml:coordinates>5,2 1.27875,-3.66875</gml:coordinates></gml:LineString></ogr:geometryProperty>
+      <ogr:id>4</ogr:id>
+      <ogr:id2>2</ogr:id2>
+      <ogr:fid_2>spoke_points.4</ogr:fid_2>
+      <ogr:id_2>4</ogr:id_2>
+      <ogr:name>point 4a</ogr:name>
+    </ogr:hub_lines>
+  </gml:featureMember>
+  <gml:featureMember>
+    <ogr:hub_lines fid="points.3">
+      <ogr:geometryProperty><gml:LineString srsName="EPSG:4326"><gml:coordinates>5,2 3.81625,-4.1675</gml:coordinates></gml:LineString></ogr:geometryProperty>
+      <ogr:id>4</ogr:id>
+      <ogr:id2>2</ogr:id2>
+      <ogr:fid_2>spoke_points.5</ogr:fid_2>
+      <ogr:id_2>4</ogr:id_2>
+      <ogr:name>point 4b</ogr:name>
+    </ogr:hub_lines>
+  </gml:featureMember>
+  <gml:featureMember>
+    <ogr:hub_lines fid="points.7">
+      <ogr:geometryProperty><gml:LineString srsName="EPSG:4326"><gml:coordinates>7,-1 6.82625,-2.79375</gml:coordinates></gml:LineString></ogr:geometryProperty>
+      <ogr:id>8</ogr:id>
+      <ogr:id2>0</ogr:id2>
+      <ogr:fid_2>spoke_points.6</ogr:fid_2>
+      <ogr:id_2>8</ogr:id_2>
+      <ogr:name>point 8</ogr:name>
+    </ogr:hub_lines>
+  </gml:featureMember>
+</ogr:FeatureCollection>
--- a/python/plugins/processing/tests/testdata/qgis_algorithm_tests.yaml
+++ b/python/plugins/processing/tests/testdata/qgis_algorithm_tests.yaml
@ -2216,6 +2216,22 @@ tests:
        name: expected/hub_distance_lines.gml
        type: vector

+  - algorithm: qgis:hublines
+    name: Hub lines
+    params:
+      HUBS:
+        name: points.gml
+        type: vector
+      SPOKES:
+        name: custom/spoke_points.gml
+        type: vector
+      HUB_FIELD: id
+      SPOKE_FIELD: id
+    results:
+      OUTPUT:
+        name: expected/hub_lines.gml
+        type: vector
+
 #  - algorithm: qgis:joinattributestable
 #    name: join the attribute table by common field
 #    params: