AAE-1665 Add missing ElResolvers to output mapping expressions (#3122)

In addition to MapResolver, other base resolver should be included as well, i.e. ListELResolver, JsonNodeELResolver

activiti-core/activiti-engine/src/main/java/org/activiti/engine/impl/el/ExpressionManager.java

 /* Licensed 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.
@@ -111,14 +111,17 @@ public class ExpressionManager {
     protected ELResolver createElResolver(VariableScope variableScope) {
         CompositeELResolver elResolver = new CompositeELResolver();
         elResolver.add(new VariableScopeElResolver(variableScope));
-
         if (beans != null) {
             // ACT-1102: Also expose all beans in configuration when using
             // standalone activiti, not
             // in spring-context
             elResolver.add(new ReadOnlyMapELResolver(beans));
         }
+        addBaseResolvers(elResolver);
+        return elResolver;
+    }
 
+    private void addBaseResolvers(CompositeELResolver elResolver) {
         elResolver.add(new ArrayELResolver());
         elResolver.add(new ListELResolver());
         elResolver.add(new MapELResolver());
@@ -127,7 +130,6 @@ public class ExpressionManager {
                                                          "getFieldValue",
                                                          "setFieldValue")); // TODO: needs verification
         elResolver.add(new BeanELResolver());
-        return elResolver;
     }
 
     public Map<Object, Object> getBeans() {
@@ -139,7 +141,9 @@ public class ExpressionManager {
     }
 
     public ELContext getElContext(Map<String, Object> availableVariables) {
-        ELResolver elResolver = new ReadOnlyMapELResolver(new HashMap<>(availableVariables));
+        CompositeELResolver elResolver = new CompositeELResolver();
+        elResolver.add(new ReadOnlyMapELResolver(new HashMap<>(availableVariables)));
+        addBaseResolvers(elResolver);
         return new ActivitiElContext(elResolver);
     }
 }

activiti-core/activiti-spring-boot-starter/src/test/java/org/activiti/spring/boot/RuntimeTestConfiguration.java

@@ -3,6 +3,8 @@ package org.activiti.spring.boot;
 import static org.assertj.core.api.Assertions.assertThat;
 import static org.assertj.core.api.Assertions.tuple;
 
+import com.fasterxml.jackson.databind.JsonNode;
+import com.fasterxml.jackson.databind.ObjectMapper;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.HashMap;
@@ -10,7 +12,6 @@ import java.util.HashSet;
 import java.util.List;
 import java.util.Map;
 import java.util.Set;
-
 import org.activiti.api.model.shared.event.VariableCreatedEvent;
 import org.activiti.api.process.model.events.BPMNSequenceFlowTakenEvent;
 import org.activiti.api.process.runtime.connector.Connector;
@@ -18,7 +19,12 @@ import org.activiti.api.process.runtime.events.ProcessCompletedEvent;
 import org.activiti.api.process.runtime.events.listener.BPMNElementEventListener;
 import org.activiti.api.process.runtime.events.listener.ProcessRuntimeEventListener;
 import org.activiti.api.runtime.shared.events.VariableEventListener;
-import org.activiti.api.task.runtime.events.*;
+import org.activiti.api.task.runtime.events.TaskCandidateGroupAddedEvent;
+import org.activiti.api.task.runtime.events.TaskCandidateGroupRemovedEvent;
+import org.activiti.api.task.runtime.events.TaskCandidateUserAddedEvent;
+import org.activiti.api.task.runtime.events.TaskCandidateUserRemovedEvent;
+import org.activiti.api.task.runtime.events.TaskCreatedEvent;
+import org.activiti.api.task.runtime.events.TaskUpdatedEvent;
 import org.activiti.api.task.runtime.events.listener.TaskRuntimeEventListener;
 import org.activiti.core.common.spring.identity.ExtendedInMemoryUserDetailsManager;
 import org.activiti.spring.boot.process.ProcessBaseRuntime;
@@ -37,9 +43,9 @@ import org.springframework.security.core.userdetails.User;
 import org.springframework.security.core.userdetails.UserDetailsService;
 
 @Configuration
-@Import({ProcessCleanUpUtil.class, 
-         TaskCleanUpUtil.class, 
-         SecurityUtil.class, 
+@Import({ProcessCleanUpUtil.class,
+         TaskCleanUpUtil.class,
+         SecurityUtil.class,
          ProcessBaseRuntime.class,
          TaskBaseRuntime.class})
 public class RuntimeTestConfiguration {
@@ -193,7 +199,7 @@ public class RuntimeTestConfiguration {
     public BPMNElementEventListener<BPMNSequenceFlowTakenEvent> sequenceFlowTakenEventListener() {
         return sequenceFlowTakenEvent -> sequenceFlowTakenEvents.add(sequenceFlowTakenEvent);
     }
-    
+
     @Bean
     public VariableEventListener<VariableCreatedEvent> variableCreatedEventFromProcessInstanceListener() {
         return variableCreatedEvent -> {
@@ -253,7 +259,7 @@ public class RuntimeTestConfiguration {
                                   "a static value"),
                             tuple(integerConstant,
                                   10));
-            
+
             integrationContext.addOutBoundVariable("out_variable_name_1",
                                                    "outName");
             integrationContext.addOutBoundVariable("out_variable_name_2",
@@ -265,7 +271,7 @@ public class RuntimeTestConfiguration {
             return integrationContext;
         };
     }
-    
+
     @Bean(name = "Variable Mapping Expression Connector.variableMappingExpressionActionName")
     public Connector variableMappingExpressionActionName() {
         return integrationContext -> {
@@ -346,10 +352,17 @@ public class RuntimeTestConfiguration {
     }
 
     @Bean(name = "OutputMappingExpValueConnector.outputMappingExpValueActionName")
-    public Connector outputMappingValueExpressionActionName() {
+    public Connector outputMappingValueExpressionActionName() throws Exception {
+        JsonNode value = new ObjectMapper().readTree("{\n"
+            + "  \"city\": {\n"
+            + "    \"name\": \"London\",\n"
+            + "    \"place\": \"Tower of London\"\n"
+            + "  }\n"
+            + "}");
         return integrationContext -> {
             integrationContext.addOutBoundVariable("outVariable1Name",
-                                                   "value-set-in-connector");
+                "value-set-in-connector");
+            integrationContext.addOutBoundVariable("sightSeeing", value);
             return integrationContext;
         };
     }

activiti-core/activiti-spring-boot-starter/src/test/java/org/activiti/spring/boot/process/ProcessRuntimeVariableMappingTest.java

@@ -129,7 +129,8 @@ public class ProcessRuntimeVariableMappingTest {
                                          VariableInstance::getValue)
                              .containsOnly(
                                            tuple("name", "John"),
-                                           tuple("outVar", "Resolved expression: value-set-in-connector"));
+                                           tuple("outVar", "Resolved expression: value-set-in-connector"),
+                                 tuple("outVarFromJsonExpression", "Tower of London"));
 
     }
 }

activiti-core/activiti-spring-boot-starter/src/test/resources/processes/output-mapping-expression-value-extensions.json

@@ -16,6 +16,12 @@
           "name": "outVar",
           "type": "string",
           "required": false
+        },
+        "outVarFromJsonExpressionId": {
+          "id": "outVarFromJsonExpressionId",
+          "name": "outVarFromJsonExpression",
+          "type": "string",
+          "required": false
         }
       },
       "mappings": {
@@ -24,6 +30,10 @@
             "outVar": {
               "type": "value",
               "value": "Resolved expression: ${outVariable1Name}"
+            },
+            "outVarFromJsonExpression": {
+              "type": "value",
+              "value": "${sightSeeing.city.place}"
             }
           }
         }