Refactor and rename GeoScript to GeoSimplifyScript

Author: Julien Delbourgo

README.md

@@ -292,17 +292,15 @@ Example :
 }
 ```
 
-## Geo preview with shape simplification and conversion
+## Geo Simplify (geo shape simplification script)
 
-This script adds a generated field containing the simplified or converted geoshape for the requested field.
+This script adds a generated field containing the simplified geoshape for the requested field.
 
 It takes parameters that can passed in a `POST` request body:
- - `geoshapestringfield` (mandatory): `geo` field name. Must be of type `geo`
- - `simplify` : boolean for whether or not the shape should be simplified according to zoom level
- - `zoom` : the zoom level for simplification (1 giving the most simplified result, mandatory if simplify=true)
- - `output_format` : format of the output (can be `geojson`, `wkt` or `wkb`, defaults to `geojson`)
+ - `field` (mandatory): `geo` field name. Must be of type `geo`
+ - `zoom` (mandatory) : the zoom level for simplification, 1 giving the most simplified result
+ - `output_format` : format of the output, can be `geojson` (default), `wkt` or `wkb`
  - `algorithm` : algorithm used for simplification, can be `douglas_peucker` (default) or `topology_preserving`
- - `is_point` : boolean (defaults to false) used to indicate the shape is a point
 
 Example:
 
@@ -312,12 +310,11 @@ Example:
 {
   "script_fields": {
     "simplified": {
-      "script": "geopreview",
+      "script": "geo_simplify",
       "lang":"native",
       "params": {
-        "geoshapestringfield": "geo_shape",
-        "zoom": 3,
-        "simplify": true
+        "field": "geo_shape",
+        "zoom": 3
       }
     }
   }
@@ -334,9 +331,35 @@ Example:
     "failed": 0
   },
   "hits": {
-    "total": 1,
+    "total": 3,
     "max_score": 1,
     "hits": [
+      {
+        "_index": "test_index_geo",
+        "_type": "records",
+        "_id": "AVrxb8fMCjSOdtKpLj4q",
+        "_score": 1,
+        "fields": {
+          "simplified": [
+            {
+              "real_type": "Point",
+              "geom": "{\"type\":\"Point\",\"coordinates\":[-14,20]}",
+              "type": "Point"
+            }
+          ]
+        }
+      },
+      {
+        "_index": "test_index_geo",
+        "_type": "records",
+        "_id": "AVrxcBv4CjSOdtKpLj4r",
+        "_score": 1,
+        "fields": {
+          "simplified": [
+            {}
+          ]
+        }
+      },
       {
         "_index": "test_index_geo",
         "_type": "records",

src/main/java/com/opendatasoft/elasticsearch/odsscript/GeoScript.java renamed to src/main/java/com/opendatasoft/elasticsearch/odsscript/GeoSimplifyScript.java

@@ -1,6 +1,5 @@
 package com.opendatasoft.elasticsearch.odsscript;
 
-import com.vividsolutions.jts.geom.Coordinate;
 import com.vividsolutions.jts.geom.Geometry;
 import com.vividsolutions.jts.geom.GeometryFactory;
 import com.vividsolutions.jts.io.ParseException;
@@ -12,7 +11,6 @@
 import org.apache.lucene.index.AtomicReaderContext;
 import org.apache.lucene.util.BytesRef;
 import org.elasticsearch.common.Base64;
-import org.elasticsearch.index.fielddata.ScriptDocValues;
 import org.elasticsearch.index.fielddata.SortedBinaryDocValues;
 import org.elasticsearch.index.mapper.FieldMapper;
 import org.elasticsearch.script.AbstractSearchScript;
@@ -22,21 +20,15 @@
 import java.util.HashMap;
 import java.util.Map;
 
-/*
- *  Copied from elasticsearch-ext-opendatasoft/GeoPreviewPlugin
- */
-class GeoScript extends AbstractSearchScript {
-
-    private final String geoShapeStringFieldName;
+class GeoSimplifyScript extends AbstractSearchScript {
 
+    private final String fieldName;
     private final double epsilon;
     private final WKTWriter wktWriter;
     private final WKBWriter wkbWriter;
     private final GeometryJSON geometryJSON;
     private final OutputFormat outputFormat;
     private final Algorithm algorithm;
-    private final boolean isPoint;
-    private final boolean simplify;
     private AtomicReaderContext currentContext;
     private int docId;
 
@@ -51,16 +43,14 @@ enum Algorithm {
         TOPOLOGY_PRESERVING
     }
 
-    public GeoScript(String geoShapeStringField, double epsilon, int coordDecimalsTrunc, OutputFormat outputFormat, Algorithm algorithm, boolean isPoint, boolean simplify) {
-        this.geoShapeStringFieldName = geoShapeStringField;
+    public GeoSimplifyScript(String field, double epsilon, int coordDecimalsTrunc, OutputFormat outputFormat, Algorithm algorithm) {
+        this.fieldName = field;
         this.epsilon = epsilon;
         this.wktWriter = new WKTWriter();
         this.wkbWriter = new WKBWriter();
         this.geometryJSON = new GeometryJSON(coordDecimalsTrunc);
         this.outputFormat = outputFormat;
         this.algorithm = algorithm;
-        this.isPoint = isPoint;
-        this.simplify = simplify;
     }
 
     private String outputGeometry(Geometry geo) {
@@ -102,44 +92,39 @@ public Object run() {
         GeometryFactory geometryFactory = new GeometryFactory();
         Map<String, String> resMap = new HashMap<>();
 
-        if (isPoint) {
-            ScriptDocValues.GeoPoints geoPoints = (ScriptDocValues.GeoPoints) doc().get(this.geoShapeStringFieldName);
-            Geometry geom = geometryFactory.createPoint(new Coordinate(geoPoints.getLon(), geoPoints.getLat()));
-
-            resMap.put("geom", outputGeometry(geom));
-            resMap.put("type", geom.getGeometryType());
-            resMap.put("real_type", geom.getGeometryType());
-
-
-        } else {
-            FieldMapper mapper = doc().mapperService().smartNameFieldMapper(this.geoShapeStringFieldName + ".wkb");
-            SortedBinaryDocValues bytes = doc().fieldDataService().getForField(mapper).load(currentContext).getBytesValues();
-            bytes.setDocument(docId);
-            BytesRef wkb = bytes.valueAt(0);
-            WKBReader reader = new WKBReader();
-
-            try {
-                Geometry geometry = reader.read(wkb.bytes);
-                String realType = geometry.getGeometryType();
-                if (simplify) {
-                    geometry = getSimplifiedShape(geometry);
-                }
-                if (!geometry.isEmpty()) {
-                    resMap.put("geom", outputGeometry(geometry));
-                    resMap.put("type", geometry.getGeometryType());
-                    resMap.put("real_type", realType);
-                } else {
-                    // If the simplified polygon is empty because it was too small, return a point
-
-                    Geometry point = geometryFactory.createPoint(geometry.getCoordinate());
-
-                    resMap.put("geom", outputGeometry(point));
-                    resMap.put("type", "SimplificationPoint");
-                }
-            } catch (ParseException e) {
-                throw new ScriptException("Can't parse WKB", e);
+        FieldMapper mapper = doc().mapperService().smartNameFieldMapper(this.fieldName + ".wkb");
+        if (mapper == null) {
+            return resMap;
+        }
+        SortedBinaryDocValues bytes = doc().fieldDataService().getForField(mapper).load(currentContext).getBytesValues();
+        bytes.setDocument(docId);
+
+        BytesRef wkb;
+        try {
+            wkb = bytes.valueAt(0);
+        } catch (ArrayIndexOutOfBoundsException e) {
+            return resMap;
+        }
+        WKBReader reader = new WKBReader();
+
+        try {
+            Geometry geometry = reader.read(wkb.bytes);
+            String realType = geometry.getGeometryType();
+            geometry = getSimplifiedShape(geometry);
+            if (!geometry.isEmpty()) {
+                resMap.put("geom", outputGeometry(geometry));
+                resMap.put("type", geometry.getGeometryType());
+                resMap.put("real_type", realType);
+            } else {
+                // If the simplified polygon is empty because it was too small, return a point
+                Geometry point = geometryFactory.createPoint(geometry.getCoordinate());
+                resMap.put("geom", outputGeometry(point));
+                resMap.put("type", "SimplificationPoint");
             }
+        } catch (ParseException e) {
+            throw new ScriptException("Can't parse WKB", e);
         }
+
         return resMap;
     }
 }

src/main/java/com/opendatasoft/elasticsearch/odsscript/OdsScriptFactory.java

@@ -7,36 +7,25 @@
 
 import java.util.Map;
 
-/*
- *  Copied from elasticsearch-ext-opendatasoft/GeoPreviewPlugin
- */
 public class OdsScriptFactory implements NativeScriptFactory {
 
     @Override
     public ExecutableScript newScript(@Nullable Map<String, Object> params) {
-        // geoshapestringfield and zoom are mandatory
 
         if (params == null) {
-            // throw npe error
+            throw new ElasticsearchIllegalArgumentException("'params' field is mandatory");
         }
 
-        String geoShapeStringField = (String) params.get("geoshapestringfield");
+        String field = (String) params.get("field");
 
-
-        if (geoShapeStringField == null) {
-            throw new ElasticsearchIllegalArgumentException("Missing the geoshapestringfield parameter");
-        }
-
-        Boolean simplify = (Boolean) params.get("simplify");
-
-        if (simplify == null) {
-            simplify = false;
+        if (field == null) {
+            throw new ElasticsearchIllegalArgumentException("'field' parameter is mandatory");
         }
 
         Integer zoom = (Integer) params.get("zoom");
 
-        if (simplify && zoom == null) {
-            throw new ElasticsearchIllegalArgumentException("Missing the zoom parameter");
+        if (zoom == null) {
+            throw new ElasticsearchIllegalArgumentException("'zoom' parameter is mandatory");
         }
 
         double tolerance = 360 / (256 * Math.pow(zoom, 3));
@@ -45,26 +34,20 @@ public ExecutableScript newScript(@Nullable Map<String, Object> params) {
 
         String stringOutputFormat = (String) params.get("output_format");
 
-        GeoScript.OutputFormat outputFormat = GeoScript.OutputFormat.GEOJSON;
+        GeoSimplifyScript.OutputFormat outputFormat = GeoSimplifyScript.OutputFormat.GEOJSON;
 
         if (stringOutputFormat != null) {
-            outputFormat = GeoScript.OutputFormat.valueOf(stringOutputFormat.toUpperCase());
+            outputFormat = GeoSimplifyScript.OutputFormat.valueOf(stringOutputFormat.toUpperCase());
         }
 
         String algorithmString = (String) params.get("algorithm");
 
-        GeoScript.Algorithm algorithm = GeoScript.Algorithm.DOUGLAS_PEUCKER;
+        GeoSimplifyScript.Algorithm algorithm = GeoSimplifyScript.Algorithm.DOUGLAS_PEUCKER;
 
         if (algorithmString != null) {
-            algorithm = GeoScript.Algorithm.valueOf(algorithmString.toUpperCase());
-        }
-
-        Boolean isPoint = (Boolean) params.get("is_point");
-
-        if (isPoint == null) {
-            isPoint = false;
+            algorithm = GeoSimplifyScript.Algorithm.valueOf(algorithmString.toUpperCase());
         }
 
-        return new GeoScript(geoShapeStringField, tolerance, nbDecimals, outputFormat, algorithm, isPoint, simplify);
+        return new GeoSimplifyScript(field, tolerance, nbDecimals, outputFormat, algorithm);
     }
 }

src/main/java/com/opendatasoft/elasticsearch/plugin/geo/GeoPlugin.java

@@ -65,6 +65,6 @@ public void onModule(AggregationModule aggModule) {
     }
 
     public void onModule(ScriptModule module) {
-        module.registerScript("geopreview", OdsScriptFactory.class);
+        module.registerScript("geo_simplify", OdsScriptFactory.class);
     }
 }