Merge pull request #6 from Trihydro/bug/14729-buffer-dead-end-before-threshold

Fix Dead End Bug when Threshold Not Met

Author: payneBrandon

web-bundle/src/main/java/com/graphhopper/resources/BufferResource.java

@@ -339,6 +339,9 @@ private BufferFeature computeEdgeAtDistanceThreshold(final BufferFeature startFe
                 nodeAccess.getLat(currentNode), nodeAccess.getLon(currentNode));
         double previousDistance = 0.0;
         Integer currentEdge = -1;
+        // Create previous values to use in case we don't meet the threshold
+        Integer previousEdge = currentEdge;
+        int previousNode = currentNode;
 
         if (currentDistance >= thresholdDistance) {
             return startFeature;
@@ -431,7 +434,12 @@ else if (tempState.get(this.roundaboutAccessEnc)) {
                     currentEdge = potentialRoundaboutEdgesWithoutName.get(0);
                     usedEdges.add(currentEdge);
                 } else {
-                    throw new WebApplicationException("Dead end found.");
+                    // Instead of throwing an exception, we break the loop and return the
+                    // path up to the current edge even though we haven't met the threshold.
+                    // Assign current edge & node to previous and break the loop.
+                    currentEdge = previousEdge;
+                    currentNode = previousNode;
+                    break;
                 }
             }
 
@@ -462,6 +470,9 @@ else if (tempState.get(this.roundaboutAccessEnc)) {
             // Move to next node
             currentNode = otherNode;
             currentState = graph.getEdgeIteratorState(currentEdge, Integer.MIN_VALUE);
+            // Update previous values
+            previousEdge = currentEdge;
+            previousNode = currentNode;
         }
 
         return new BufferFeature(currentEdge, currentNode,

web/src/test/java/com/graphhopper/application/resources/BufferResourceTest.java

@@ -31,14 +31,14 @@ public class BufferResourceTest {
     private static GraphHopperServerConfiguration createConfig() {
         GraphHopperServerConfiguration config = new GraphHopperServerTestConfiguration();
         config.getGraphHopperConfiguration()
-                .putObject("datareader.file", "../core/files/andorra.osm.pbf")
-                .putObject("import.osm.ignored_highways", "")
-                .putObject("graph.location", DIR)
-                .putObject("graph.encoded_values", "car_access, car_average_speed")
-                .setProfiles(Arrays.asList(
-                        TestProfiles.accessAndSpeed("fast_car", "car").setTurnCostsConfig(TurnCostsConfig.car()),
-                        TestProfiles.constantSpeed("short_car", 35).setTurnCostsConfig(TurnCostsConfig.car()),
-                        TestProfiles.accessAndSpeed("fast_car_no_turn_restrictions", "car")));
+            .putObject("datareader.file", "../core/files/andorra.osm.pbf")
+            .putObject("import.osm.ignored_highways", "")
+            .putObject("graph.location", DIR)
+            .putObject("graph.encoded_values", "car_access, car_average_speed")
+            .setProfiles(Arrays.asList(
+                TestProfiles.accessAndSpeed("fast_car", "car").setTurnCostsConfig(TurnCostsConfig.car()),
+                TestProfiles.constantSpeed("short_car", 35).setTurnCostsConfig(TurnCostsConfig.car()),
+                TestProfiles.accessAndSpeed("fast_car_no_turn_restrictions", "car")));
         return config;
     }
 
@@ -333,4 +333,31 @@ public void testUnusualRoadNameFormat() {
             assertEquals(200, response.getStatus());
         }
     }
+
+    @Test
+    public void testOutOfRoad() {
+        // testing buffer on a road in Andorra that transitions from CG-1 to N-145
+        JsonFeatureCollection featureCollection;
+        try (Response response = clientTarget(app, "/buffer?profile=my_car&"
+            + "point=42.440606,1.477431&roadName=cg-1&"
+            + "thresholdDistance=1600&buildUpstream=true&queryMultiplier=0.000075").request()
+                .buildGet().invoke()) {
+            assertEquals(200, response.getStatus());
+            featureCollection = response.readEntity(JsonFeatureCollection.class);
+        }
+
+        assertEquals(2, featureCollection.getFeatures().size());
+        Geometry lineString0 = featureCollection.getFeatures().get(0).getGeometry();
+        Geometry lineString1 = featureCollection.getFeatures().get(1).getGeometry();
+
+        // Identical start points (reversed index)
+        assertEquals(lineString0.getCoordinates()[lineString0.getCoordinates().length - 1],
+                lineString1.getCoordinates()[lineString1.getCoordinates().length - 1]);
+
+        // Different end points (reversed index)
+        assertNotEquals(lineString0.getCoordinates()[0], lineString1.getCoordinates()[0]);
+
+        // Check lengths are different since one path runs out of road
+        assertNotEquals(lineString0.getLength(), lineString1.getLength());
+    }
 }