Scripting: JSON parsing and writing in watcher

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

@@ -0,0 +1,75 @@
+/*
+ * 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 {
+    /**
+     * Load a string as the Java version of a JSON type, either List (JSON array), Map (JSON object), Number, Boolean or String
+     */
+    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;
+        }
+    }
+
+    /**
+     * Write a JSON representable type as a string
+     */
+    public static String dump(Object data) throws IOException {
+      return dump(data, false);
+    }
+
+    /**
+     * Write a JSON representable type as a string, optionally pretty print it by spanning multiple lines and indenting
+     */
+    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 +1,50 @@
+/*
+ * 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);
+    }
+
+}

modules/lang-painless/src/test/resources/org/elasticsearch/painless/spi/org.elasticsearch.painless.test

@@ -5,6 +5,13 @@ class org.elasticsearch.script.JodaCompatibleZonedDateTime {
   (Instant, ZoneId)
 }
 
+# for unit tests only
+class org.elasticsearch.painless.api.Json {
+  def load(String)
+  String dump(def)
+  String dump(def,boolean)
+}
+
 class org.elasticsearch.painless.BindingsTests$BindingsTestScript {
 }
 

x-pack/plugin/watcher/qa/rest/src/yamlRestTest/resources/rest-api-spec/test/painless/70_json_in_watch.yml

@@ -0,0 +1,58 @@
+---
+"Test json in watch":
+
+  - do:
+      cluster.health:
+        wait_for_status: green
+
+  - do:
+      watcher.put_watch:
+        id: "my_json_watch"
+        body:  >
+          {
+            "trigger" : {
+              "schedule" : { "cron" : "0 0 0 1 * ? 2099" }
+            },
+            "input" : {
+              "simple" : {
+                "count" : 1
+              }
+            },
+            "condition" : {
+              "script" : {
+                "source" : "String s = Json.dump(ctx.payload); Map m = Json.load(s); m.count == 1;",
+                "lang" : "painless"
+              }
+            },
+            "transform" : {
+              "script": "String s = Json.dump(ctx.payload); Map m = Json.load(s); return ['test': m];"
+            },
+            "actions" : {
+              "logging" : {
+                "logging" : {
+                  "text" : "{{ctx.payload.test.count}}"
+                }
+              }
+            }
+          }
+  - match: { _id: "my_json_watch" }
+
+  - do:
+      watcher.execute_watch:
+        id: "my_json_watch"
+
+  - match: { "watch_record.watch_id": "my_json_watch" }
+  - match: { "watch_record.state": "executed" }
+  - match: { "watch_record.result.input.type": "simple" }
+  - match: { "watch_record.result.input.status": "success" }
+  - match: { "watch_record.result.input.payload.count": 1 }
+  - match: { "watch_record.result.condition.type": "script" }
+  - match: { "watch_record.result.condition.status": "success" }
+  - match: { "watch_record.result.condition.met": true }
+  - match: { "watch_record.result.transform.type": "script" }
+  - match: { "watch_record.result.transform.status": "success" }
+  - match: { "watch_record.result.transform.payload.test.count": 1 }
+  - match: { "watch_record.result.actions.0.id" : "logging" }
+  - match: { "watch_record.result.actions.0.type" : "logging" }
+  - match: { "watch_record.result.actions.0.status" : "success" }
+  - match: { "watch_record.result.actions.0.logging.logged_text" : "1" }

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

@@ -8,3 +8,9 @@ class java.lang.String {
   String org.elasticsearch.painless.api.Augmentation sha1()
   String org.elasticsearch.painless.api.Augmentation sha256()
 }
+
+class org.elasticsearch.painless.api.Json {
+  def load(String)
+  String dump(def)
+  String dump(def, boolean)
+}