Json support in painless

docs/painless/painless-api-reference/painless-api-reference-shared/index.asciidoc

@@ -420,6 +420,7 @@ The following classes are available grouped by their respective packages. Click
 <<painless-api-reference-shared-org-elasticsearch-painless-api, Expand details for org.elasticsearch.painless.api>>
 
 * <<painless-api-reference-shared-Debug, Debug>>
+* <<painless-api-reference-shared-Json, Json>>
 
 ==== org.elasticsearch.script
 <<painless-api-reference-shared-org-elasticsearch-script, Expand details for org.elasticsearch.script>>

docs/painless/painless-api-reference/painless-api-reference-shared/packages.asciidoc

@@ -8509,6 +8509,12 @@ See the <<painless-api-reference-shared, Shared API>> for a high-level overview
 === Shared API for package org.elasticsearch.script
 See the <<painless-api-reference-shared, Shared API>> for a high-level overview of all packages and classes.
 
+[[painless-api-reference-shared-Json]]
+==== Json
+*  static def load(String)
+*  static String dump(Object)
+*  static String dump(Object, boolean)
+
 [[painless-api-reference-shared-JodaCompatibleZonedDateTime]]
 ==== JodaCompatibleZonedDateTime
 * int {java11-javadoc}/java.base/java/time/chrono/ChronoZonedDateTime.html#compareTo(java.time.chrono.ChronoZonedDateTime)[compareTo](ChronoZonedDateTime)

modules/lang-painless/src/main/java/org/elasticsearch/painless/api/Json.java

@@ -0,0 +1,66 @@
+/*
+ * 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.painless.api;
+
+import org.elasticsearch.common.xcontent.DeprecationHandler;
+import org.elasticsearch.common.xcontent.NamedXContentRegistry;
+import org.elasticsearch.common.xcontent.XContentBuilder;
+import org.elasticsearch.common.xcontent.XContentParser;
+import org.elasticsearch.common.xcontent.json.JsonXContent;
+
+import java.io.IOException;
+
+public class Json {
+    public static Object load(String json) throws IOException{
+        XContentParser parser = JsonXContent.jsonXContent.createParser(
+            NamedXContentRegistry.EMPTY,
+            DeprecationHandler.THROW_UNSUPPORTED_OPERATION,
+            json);
+
+        switch (parser.nextToken()) {
+            case START_ARRAY:
+                return parser.list();
+            case START_OBJECT:
+                return parser.map();
+            case VALUE_NUMBER:
+                return parser.numberValue();
+            case VALUE_BOOLEAN:
+                return parser.booleanValue();
+            case VALUE_STRING:
+                return parser.text();
+            default:
+                return null;
+        }
+    }
+
+    public static String dump(Object data) throws IOException {
+      return dump(data, false);
+    }
+
+    public static String dump(Object data, boolean pretty) throws IOException {
+        XContentBuilder builder = JsonXContent.contentBuilder();
+        if (pretty) {
+            builder.prettyPrint();
+        }
+        builder.value(data);
+        builder.flush();
+        return builder.getOutputStream().toString();
+    }
+}

modules/lang-painless/src/test/java/org/elasticsearch/painless/JsonTests.java

@@ -0,0 +1,49 @@
+/*
+ * 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.painless;
+
+import static java.util.Collections.singletonList;
+import static java.util.Collections.singletonMap;
+
+public class JsonTests extends ScriptTestCase {
+    public void testDump() {
+        // simple object dump
+        Object output = exec("Json.dump(params.data)", singletonMap("data", singletonMap("hello", "world")), true);
+        assertEquals("{\"hello\":\"world\"}", output);
+
+        output = exec("Json.dump(params.data)", singletonMap("data", singletonList(42)), true);
+        assertEquals("[42]", output);
+
+        // pretty print
+        output = exec("Json.dump(params.data, true)", singletonMap("data", singletonMap("hello", "world")), true);
+        assertEquals("{\n  \"hello\" : \"world\"\n}", output);
+    }
+
+    public void testLoad() {
+        String json = "{\"hello\":\"world\"}";
+        Object output = exec("Json.load(params.json)", singletonMap("json", json), true);
+        assertEquals(singletonMap("hello", "world"), output);
+
+        json = "[42]";
+        output = exec("Json.load(params.json)", singletonMap("json", json), true);
+        assertEquals(singletonList(42), output);
+    }
+
+}

x-pack/plugin/watcher/build.gradle

@@ -5,7 +5,7 @@ esplugin {
   classname 'org.elasticsearch.xpack.watcher.Watcher'
   hasNativeController false
   requiresKeystore false
-  extendedPlugins = ['x-pack-core']
+  extendedPlugins = ['x-pack-core', 'lang-painless']
 }
 
 archivesBaseName = 'x-pack-watcher'
@@ -21,6 +21,7 @@ tasks.named("dependencyLicenses").configure {
 
 dependencies {
   compileOnly project(':server')
+  compileOnly project(':modules:lang-painless:spi')
   compileOnly project(path: xpackModule('core'), configuration: 'default')
   compileOnly project(path: ':modules:transport-netty4')
   compileOnly project(path: ':plugins:transport-nio')

x-pack/plugin/watcher/qa/rest/src/test/resources/rest-api-spec/test/watcher/execute_watch/90_painless_context.yml

@@ -0,0 +1,55 @@
+---
+"Test for json (de)serialization in painless' watcher context":
+  - do:
+      watcher.execute_watch:
+        body: >
+          {
+            "watch": {
+              "trigger": {
+                "schedule" : { "cron" : "0 0 0 1 * ? 2099" }
+              },
+              "input": {
+                "simple": {
+                  "foo": "bar"
+                }
+              },
+              "condition": {
+                "script": {
+                  "source": "Json.dump([1, 2, 3, 4]) == '[1,2,3,4]'"
+                }
+              },
+              "transform": {
+                "script": {
+                  "source": "return Json.load('{\"hello\": \"world\"}')"
+                }
+              },
+              "actions": {
+                "indexme" : {
+                  "index" : {
+                    "index" : "my_test_index",
+                    "doc_id": "my-id"
+                  }
+                }
+              }
+            }
+          }
+
+  - match: { watch_record.trigger_event.type: "manual" }
+  - match: { watch_record.state: "executed" }
+  - match: { watch_record.status.execution_state: "executed" }
+  - match: { watch_record.status.state.active: true }
+  - is_true: watch_record.node
+  - match: { watch_record.status.actions.indexme.ack.state: "ackable" }
+  - gt: { watch_record.result.execution_duration: 0 }
+
+  - do:
+      indices.refresh: {}
+
+  - do:
+      get:
+        index: my_test_index
+        id: my-id
+
+  - match: { found: true }
+  - match: { _source.hello: world }
+

x-pack/plugin/watcher/src/main/java/org/elasticsearch/xpack/watcher/Watcher.java

@@ -178,6 +178,7 @@
 import java.io.IOException;
 import java.io.UncheckedIOException;
 import java.time.Clock;
+import java.time.Duration;
 import java.time.ZoneOffset;
 import java.time.ZonedDateTime;
 import java.util.ArrayList;

x-pack/plugin/watcher/src/main/java/org/elasticsearch/xpack/watcher/WatcherPainlessExtension.java

@@ -0,0 +1,32 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the Elastic License;
+ * you may not use this file except in compliance with the Elastic License.
+ */
+package org.elasticsearch.xpack.watcher;
+
+import org.elasticsearch.painless.spi.PainlessExtension;
+import org.elasticsearch.painless.spi.Whitelist;
+import org.elasticsearch.painless.spi.WhitelistLoader;
+import org.elasticsearch.script.ScriptContext;
+import org.elasticsearch.xpack.watcher.condition.WatcherConditionScript;
+import org.elasticsearch.xpack.watcher.transform.script.WatcherTransformScript;
+
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
+public class WatcherPainlessExtension implements PainlessExtension {
+
+    private static final Whitelist WHITELIST =
+        WhitelistLoader.loadFromResourceFiles(WatcherPainlessExtension.class, "painless_whitelist.txt");
+
+    @Override
+    public Map<ScriptContext<?>, List<Whitelist>> getContextWhitelists() {
+        Map<ScriptContext<?>, List<Whitelist>> contextWhiltelists = new HashMap<>();
+        contextWhiltelists.put(WatcherConditionScript.CONTEXT, Collections.singletonList(WHITELIST));
+        contextWhiltelists.put(WatcherTransformScript.CONTEXT, Collections.singletonList(WHITELIST));
+        return Collections.unmodifiableMap(contextWhiltelists);
+    }
+}

x-pack/plugin/watcher/src/main/resources/META-INF/services/org.elasticsearch.painless.spi.PainlessExtension

@@ -0,0 +1 @@
+org.elasticsearch.xpack.watcher.WatcherPainlessExtension

x-pack/plugin/watcher/src/main/resources/org/elasticsearch/xpack/watcher/painless_whitelist.txt

@@ -0,0 +1,15 @@
+#
+# Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+# or more contributor license agreements. Licensed under the Elastic License;
+# you may not use this file except in compliance with the Elastic License.
+#
+
+class org.elasticsearch.painless.api.Json {
+  def load(String)
+  String dump(def)
+  String dump(def, boolean)
+}
+
+static_import {
+  def load(String) from_class org.elasticsearch.painless.api.Json
+}