Feature - use environment variable to set ES6 support mode for Nashor…

…n script evaluator

core/src/main/java/com/netflix/conductor/core/events/ScriptEvaluator.java

@@ -17,6 +17,8 @@
 import javax.script.ScriptEngineManager;
 import javax.script.ScriptException;
 
+import org.openjdk.nashorn.api.scripting.NashornScriptEngineFactory;
+
 public class ScriptEvaluator {
 
     private static ScriptEngine engine;
@@ -25,7 +27,7 @@ private ScriptEvaluator() {}
 
     /**
      * Evaluates the script with the help of input provided but converts the result to a boolean
-     * value.
+     * value. Set environment variable CONDUCTOR_NASHORN_ES6_ENABLED=true for Nashorn ES6 support.
      *
      * @param script Script to be evaluated.
      * @param input Input parameters.
@@ -37,24 +39,39 @@ public static Boolean evalBool(String script, Object input) throws ScriptExcepti
     }
 
     /**
-     * Evaluates the script with the help of input provided.
+     * Evaluates the script with the help of input provided. Set environment variable
+     * CONDUCTOR_NASHORN_ES6_ENABLED=true for Nashorn ES6 support.
      *
      * @param script Script to be evaluated.
      * @param input Input parameters.
      * @throws ScriptException
      * @return Generic object, the result of the evaluated expression.
      */
     public static Object eval(String script, Object input) throws ScriptException {
-        if (engine == null) {
-            engine = new ScriptEngineManager().getEngineByName("Nashorn");
+        initEngine(false);
+        Bindings bindings = engine.createBindings();
+        bindings.put("$", input);
+        return engine.eval(script, bindings);
+    }
+
+    // to mock in a test
+    public static String getEnv(String name) {
+        return System.getenv(name);
+    }
+
+    public static void initEngine(boolean reInit) {
+        if (engine == null || reInit) {
+            if ("true".equalsIgnoreCase(getEnv("CONDUCTOR_NASHORN_ES6_ENABLED"))) {
+                NashornScriptEngineFactory factory = new NashornScriptEngineFactory();
+                engine = factory.getScriptEngine("--language=es6");
+            } else {
+                engine = new ScriptEngineManager().getEngineByName("Nashorn");
+            }
         }
         if (engine == null) {
             throw new RuntimeException(
                     "missing nashorn engine.  Ensure you are running supported JVM");
         }
-        Bindings bindings = engine.createBindings();
-        bindings.put("$", input);
-        return engine.eval(script, bindings);
     }
 
     /**

core/src/test/java/com/netflix/conductor/core/events/TestScriptEval.java

@@ -16,6 +16,8 @@
 import java.util.Map;
 
 import org.junit.Test;
+import org.mockito.MockedStatic;
+import org.mockito.Mockito;
 
 import static org.junit.Assert.assertFalse;
 import static org.junit.Assert.assertTrue;
@@ -44,4 +46,43 @@ public void testScript() throws Exception {
         assertTrue(ScriptEvaluator.evalBool(script3, payload));
         assertFalse(ScriptEvaluator.evalBool(script4, payload));
     }
+
+    @Test
+    public void testES6Setting() throws Exception {
+        Map<String, Object> payload = new HashMap<>();
+        Map<String, Object> app = new HashMap<>();
+        app.put("name", "conductor");
+        app.put("version", 2.0);
+        app.put("license", "Apache 2.0");
+
+        payload.put("app", app);
+        payload.put("author", "Netflix");
+        payload.put("oss", true);
+
+        String script1 =
+                """
+                (function(){\s
+                const variable = 1; // const support => es6\s
+                return $.app.name == 'conductor';})();"""; // true
+
+        MockedStatic<ScriptEvaluator> evaluator = Mockito.mockStatic(ScriptEvaluator.class);
+        evaluator
+                .when(() -> ScriptEvaluator.getEnv("CONDUCTOR_NASHORN_ES6_ENABLED"))
+                .thenReturn("true");
+        evaluator
+                .when(() -> ScriptEvaluator.eval(Mockito.any(), Mockito.any()))
+                .thenCallRealMethod();
+        evaluator
+                .when(() -> ScriptEvaluator.evalBool(Mockito.any(), Mockito.any()))
+                .thenCallRealMethod();
+        evaluator.when(() -> ScriptEvaluator.initEngine(Mockito.anyBoolean())).thenCallRealMethod();
+        evaluator.when(() -> ScriptEvaluator.toBoolean(Mockito.any())).thenCallRealMethod();
+        ScriptEvaluator.initEngine(true);
+        assertTrue(ScriptEvaluator.evalBool(script1, payload));
+        evaluator
+                .when(() -> ScriptEvaluator.getEnv("CONDUCTOR_NASHORN_ES6_ENABLED"))
+                .thenReturn("false");
+        ScriptEvaluator.initEngine(true);
+        evaluator.close();
+    }
 }

java-sdk/src/main/java/com/netflix/conductor/sdk/workflow/def/tasks/Javascript.java

@@ -22,6 +22,7 @@
 import javax.script.ScriptEngineManager;
 import javax.script.ScriptException;
 
+import org.openjdk.nashorn.api.scripting.NashornScriptEngineFactory;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -49,7 +50,8 @@ public class Javascript extends Task<Javascript> {
      * Javascript tasks are executed on the Conductor server without having to write worker code
      *
      * <p>Use {@link Javascript#validate()} method to validate the javascript to ensure the script
-     * is valid.
+     * is valid. Set environment variable CONDUCTOR_NASHORN_ES6_ENABLED=true for Nashorn ES6 support
+     * during validation.
      *
      * @param taskReferenceName
      * @param script script to execute
@@ -100,7 +102,13 @@ public String getExpression() {
      * @return
      */
     public Javascript validate() {
-        ScriptEngine scriptEngine = new ScriptEngineManager().getEngineByName("Nashorn");
+        ScriptEngine scriptEngine;
+        if ("true".equalsIgnoreCase(System.getenv("CONDUCTOR_NASHORN_ES6_ENABLED"))) {
+            NashornScriptEngineFactory factory = new NashornScriptEngineFactory();
+            scriptEngine = factory.getScriptEngine("--language=es6");
+        } else {
+            scriptEngine = new ScriptEngineManager().getEngineByName("Nashorn");
+        }
         if (scriptEngine == null) {
             LOGGER.error("missing " + ENGINE + " engine.  Ensure you are running supported JVM");
             return this;
@@ -128,7 +136,13 @@ public Javascript validate() {
      */
     public Object test(Map<String, Object> input) {
 
-        ScriptEngine scriptEngine = new ScriptEngineManager().getEngineByName("Nashorn");
+        ScriptEngine scriptEngine;
+        if ("true".equalsIgnoreCase(System.getenv("CONDUCTOR_NASHORN_ES6_ENABLED"))) {
+            NashornScriptEngineFactory factory = new NashornScriptEngineFactory();
+            scriptEngine = factory.getScriptEngine("--language=es6");
+        } else {
+            scriptEngine = new ScriptEngineManager().getEngineByName("Nashorn");
+        }
         if (scriptEngine == null) {
             LOGGER.error("missing " + ENGINE + " engine.  Ensure you are running supported JVM");
             return this;