SCRIPTING: Move Aggregation Scripts to their own context (#32068) (#3…

…2629)

* SCRIPTING: Move Aggregation Scripts to their own context

modules/lang-expression/src/main/java/org/elasticsearch/script/expression/ExpressionScriptEngine.java

@@ -34,10 +34,12 @@
 import org.elasticsearch.common.settings.Settings;
 import org.elasticsearch.index.fielddata.IndexFieldData;
 import org.elasticsearch.index.fielddata.IndexNumericFieldData;
-import org.elasticsearch.index.mapper.GeoPointFieldMapper.GeoPointFieldType;
 import org.elasticsearch.index.mapper.DateFieldMapper;
+import org.elasticsearch.index.mapper.GeoPointFieldMapper.GeoPointFieldType;
 import org.elasticsearch.index.mapper.MappedFieldType;
 import org.elasticsearch.index.mapper.MapperService;
+import org.elasticsearch.script.BucketAggregationScript;
+import org.elasticsearch.script.BucketAggregationSelectorScript;
 import org.elasticsearch.script.ClassPermission;
 import org.elasticsearch.script.ExecutableScript;
 import org.elasticsearch.script.FilterScript;
@@ -54,6 +56,7 @@
 import java.security.PrivilegedAction;
 import java.text.ParseException;
 import java.util.ArrayList;
+import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
 
@@ -112,6 +115,17 @@ protected Class<?> loadClass(String name, boolean resolve) throws ClassNotFoundE
         } else if (context.instanceClazz.equals(ExecutableScript.class)) {
             ExecutableScript.Factory factory = (p) -> new ExpressionExecutableScript(expr, p);
             return context.factoryClazz.cast(factory);
+        } else if (context.instanceClazz.equals(BucketAggregationScript.class)) {
+            return context.factoryClazz.cast(newBucketAggregationScriptFactory(expr));
+        } else if (context.instanceClazz.equals(BucketAggregationSelectorScript.class)) {
+            BucketAggregationScript.Factory factory = newBucketAggregationScriptFactory(expr);
+            BucketAggregationSelectorScript.Factory wrappedFactory = parameters -> new BucketAggregationSelectorScript(parameters) {
+                @Override
+                public boolean execute() {
+                    return factory.newInstance(getParams()).execute() == 1.0;
+                }
+            };
+            return context.factoryClazz.cast(wrappedFactory);
         } else if (context.instanceClazz.equals(FilterScript.class)) {
             FilterScript.Factory factory = (p, lookup) -> newFilterScript(expr, lookup, p);
             return context.factoryClazz.cast(factory);
@@ -122,6 +136,37 @@ protected Class<?> loadClass(String name, boolean resolve) throws ClassNotFoundE
         throw new IllegalArgumentException("expression engine does not know how to handle script context [" + context.name + "]");
     }
 
+    private static BucketAggregationScript.Factory newBucketAggregationScriptFactory(Expression expr) {
+        return parameters -> {
+            ReplaceableConstDoubleValues[] functionValuesArray =
+                new ReplaceableConstDoubleValues[expr.variables.length];
+            Map<String, ReplaceableConstDoubleValues> functionValuesMap = new HashMap<>();
+            for (int i = 0; i < expr.variables.length; ++i) {
+                functionValuesArray[i] = new ReplaceableConstDoubleValues();
+                functionValuesMap.put(expr.variables[i], functionValuesArray[i]);
+            }
+            return new BucketAggregationScript(parameters) {
+                @Override
+                public double execute() {
+                    getParams().forEach((name, value) -> {
+                        ReplaceableConstDoubleValues placeholder = functionValuesMap.get(name);
+                        if (placeholder == null) {
+                            throw new IllegalArgumentException("Error using " + expr + ". " +
+                                "The variable [" + name + "] does not exist in the executable expressions script.");
+                        } else if (value instanceof Number == false) {
+                            throw new IllegalArgumentException("Error using " + expr + ". " +
+                                "Executable expressions scripts can only process numbers." +
+                                "  The variable [" + name + "] is not a number.");
+                        } else {
+                            placeholder.setValue(((Number) value).doubleValue());
+                        }
+                    });
+                    return expr.evaluate(functionValuesArray);
+                }
+            };
+        };
+    }
+
     private SearchScript.LeafFactory newSearchScript(Expression expr, SearchLookup lookup, @Nullable Map<String, Object> vars) {
         MapperService mapper = lookup.doc().mapperService();
         // NOTE: if we need to do anything complicated with bindings in the future, we can just extend Bindings,
@@ -267,7 +312,7 @@ public void setDocument(int docid) {
             };
         };
     }
-    
+
     private ScoreScript.LeafFactory newScoreScript(Expression expr, SearchLookup lookup, @Nullable Map<String, Object> vars) {
         SearchScript.LeafFactory searchLeafFactory = newSearchScript(expr, lookup, vars);
         return new ScoreScript.LeafFactory() {
@@ -284,17 +329,17 @@ public ScoreScript newInstance(LeafReaderContext ctx) throws IOException {
                     public double execute() {
                         return script.runAsDouble();
                     }
-    
+
                     @Override
                     public void setDocument(int docid) {
                         script.setDocument(docid);
                     }
-    
+
                     @Override
                     public void setScorer(Scorer scorer) {
                         script.setScorer(scorer);
                     }
-    
+
                     @Override
                     public double get_score() {
                         return script.getScore();

server/src/main/java/org/elasticsearch/script/BucketAggregationScript.java

@@ -0,0 +1,54 @@
+/*
+ * Licensed to Elasticsearch under one or more contributor
+ * license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright
+ * ownership. Elasticsearch licenses this file to you under
+ * the Apache License, Version 2.0 (the "License"); you may
+ * not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+package org.elasticsearch.script;
+
+import java.util.Map;
+
+/**
+ * A script used in bucket aggregations that returns a {@code double} value.
+ */
+public abstract class BucketAggregationScript {
+
+    public static final String[] PARAMETERS = {};
+
+    public static final ScriptContext<Factory> CONTEXT = new ScriptContext<>("bucket_aggregation", Factory.class);
+
+    /**
+     * The generic runtime parameters for the script.
+     */
+    private final Map<String, Object> params;
+
+    public BucketAggregationScript(Map<String, Object> params) {
+        this.params = params;
+    }
+
+    /**
+     * Return the parameters for this script.
+     */
+    public Map<String, Object> getParams() {
+        return params;
+    }
+
+    public abstract double execute();
+
+    public interface Factory {
+        BucketAggregationScript newInstance(Map<String, Object> params);
+    }
+}

server/src/main/java/org/elasticsearch/script/BucketAggregationSelectorScript.java

@@ -0,0 +1,54 @@
+/*
+ * Licensed to Elasticsearch under one or more contributor
+ * license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright
+ * ownership. Elasticsearch licenses this file to you under
+ * the Apache License, Version 2.0 (the "License"); you may
+ * not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+package org.elasticsearch.script;
+
+import java.util.Map;
+
+/**
+ * A script used in bucket aggregations that returns a {@code boolean} value.
+ */
+public abstract class BucketAggregationSelectorScript {
+
+    public static final String[] PARAMETERS = {};
+
+    public static final ScriptContext<Factory> CONTEXT = new ScriptContext<>("aggregation_selector", Factory.class);
+
+    /**
+     * The generic runtime parameters for the script.
+     */
+    private final Map<String, Object> params;
+
+    public BucketAggregationSelectorScript(Map<String, Object> params) {
+        this.params = params;
+    }
+
+    /**
+     * Return the parameters for this script.
+     */
+    public Map<String, Object> getParams() {
+        return params;
+    }
+
+    public abstract boolean execute();
+
+    public interface Factory {
+        BucketAggregationSelectorScript newInstance(Map<String, Object> params);
+    }
+}

server/src/main/java/org/elasticsearch/script/ExecutableScript.java

@@ -48,6 +48,5 @@ interface Factory {
     ScriptContext<Factory> CONTEXT = new ScriptContext<>("executable", Factory.class);
 
     // TODO: remove these once each has its own script interface
-    ScriptContext<Factory> AGGS_CONTEXT = new ScriptContext<>("aggs_executable", Factory.class);
     ScriptContext<Factory> UPDATE_CONTEXT = new ScriptContext<>("update", Factory.class);
 }

server/src/main/java/org/elasticsearch/script/ScriptModule.java

@@ -49,7 +49,9 @@ public class ScriptModule {
             SearchScript.SCRIPT_SORT_CONTEXT,
             SearchScript.TERMS_SET_QUERY_CONTEXT,
             ExecutableScript.CONTEXT,
-            ExecutableScript.AGGS_CONTEXT,
+            BucketAggregationScript.CONTEXT,
+            BucketAggregationSelectorScript.CONTEXT,
+            SignificantTermsHeuristicScoreScript.CONTEXT,
             ExecutableScript.UPDATE_CONTEXT,
             IngestScript.CONTEXT,
             FilterScript.CONTEXT,

server/src/main/java/org/elasticsearch/script/SignificantTermsHeuristicScoreScript.java

@@ -0,0 +1,38 @@
+/*
+ * Licensed to Elasticsearch under one or more contributor
+ * license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright
+ * ownership. Elasticsearch licenses this file to you under
+ * the Apache License, Version 2.0 (the "License"); you may
+ * not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+package org.elasticsearch.script;
+
+import java.util.Map;
+
+/**
+ * A script used in significant terms heuristic scoring.
+ */
+public abstract class SignificantTermsHeuristicScoreScript {
+
+    public static final String[] PARAMETERS = { "params" };
+
+    public static final ScriptContext<Factory> CONTEXT = new ScriptContext<>("script_heuristic", Factory.class);
+
+    public abstract double execute(Map<String, Object> params);
+
+    public interface Factory {
+        SignificantTermsHeuristicScoreScript newInstance();
+    }
+}

server/src/main/java/org/elasticsearch/search/aggregations/bucket/significant/heuristics/ScriptHeuristic.java

@@ -28,12 +28,14 @@
 import org.elasticsearch.common.xcontent.XContentParser;
 import org.elasticsearch.index.query.QueryShardContext;
 import org.elasticsearch.index.query.QueryShardException;
-import org.elasticsearch.script.ExecutableScript;
 import org.elasticsearch.script.Script;
+import org.elasticsearch.script.SignificantTermsHeuristicScoreScript;
 import org.elasticsearch.search.aggregations.InternalAggregation;
 import org.elasticsearch.search.internal.SearchContext;
 
 import java.io.IOException;
+import java.util.HashMap;
+import java.util.Map;
 import java.util.Objects;
 
 public class ScriptHeuristic extends SignificanceHeuristic {
@@ -48,19 +50,21 @@ static class ExecutableScriptHeuristic extends ScriptHeuristic {
         private final LongAccessor supersetSizeHolder;
         private final LongAccessor subsetDfHolder;
         private final LongAccessor supersetDfHolder;
-        private final ExecutableScript executableScript;
+        private final SignificantTermsHeuristicScoreScript executableScript;
+        private final Map<String, Object> params = new HashMap<>();
 
-        ExecutableScriptHeuristic(Script script, ExecutableScript executableScript){
+        ExecutableScriptHeuristic(Script script, SignificantTermsHeuristicScoreScript executableScript) {
             super(script);
             subsetSizeHolder = new LongAccessor();
             supersetSizeHolder = new LongAccessor();
             subsetDfHolder = new LongAccessor();
             supersetDfHolder = new LongAccessor();
             this.executableScript = executableScript;
-            executableScript.setNextVar("_subset_freq", subsetDfHolder);
-            executableScript.setNextVar("_subset_size", subsetSizeHolder);
-            executableScript.setNextVar("_superset_freq", supersetDfHolder);
-            executableScript.setNextVar("_superset_size", supersetSizeHolder);
+            params.putAll(script.getParams());
+            params.put("_subset_freq", subsetDfHolder);
+            params.put("_subset_size", subsetSizeHolder);
+            params.put("_superset_freq", supersetDfHolder);
+            params.put("_superset_size", supersetSizeHolder);
         }
 
         @Override
@@ -69,7 +73,7 @@ public double getScore(long subsetFreq, long subsetSize, long supersetFreq, long
             supersetSizeHolder.value = supersetSize;
             subsetDfHolder.value = subsetFreq;
             supersetDfHolder.value = supersetFreq;
-            return ((Number) executableScript.run()).doubleValue();
+            return executableScript.execute(params);
        }
     }
 
@@ -91,15 +95,15 @@ public void writeTo(StreamOutput out) throws IOException {
 
     @Override
     public SignificanceHeuristic rewrite(InternalAggregation.ReduceContext context) {
-        ExecutableScript.Factory factory = context.scriptService().compile(script, ExecutableScript.AGGS_CONTEXT);
-        return new ExecutableScriptHeuristic(script, factory.newInstance(script.getParams()));
+        SignificantTermsHeuristicScoreScript.Factory factory = context.scriptService().compile(script, SignificantTermsHeuristicScoreScript.CONTEXT);
+        return new ExecutableScriptHeuristic(script, factory.newInstance());
     }
 
     @Override
     public SignificanceHeuristic rewrite(SearchContext context) {
         QueryShardContext shardContext = context.getQueryShardContext();
-        ExecutableScript.Factory compiledScript = shardContext.getScriptService().compile(script, ExecutableScript.AGGS_CONTEXT);
-        return new ExecutableScriptHeuristic(script, compiledScript.newInstance(script.getParams()));
+        SignificantTermsHeuristicScoreScript.Factory compiledScript = shardContext.getScriptService().compile(script, SignificantTermsHeuristicScoreScript.CONTEXT);
+        return new ExecutableScriptHeuristic(script, compiledScript.newInstance());
     }