handle event field names properly

ex: SQS Records with big R

Author: jeromevdl

powertools-validation/pom.xml

@@ -75,6 +75,10 @@
             <artifactId>json-schema-validator</artifactId>
             <version>1.0.73</version>
         </dependency>
+        <dependency>
+            <groupId>com.amazonaws</groupId>
+            <artifactId>aws-lambda-java-serialization</artifactId>
+        </dependency>
 
         <!-- Test dependencies -->
         <dependency>
@@ -87,11 +91,7 @@
             <artifactId>junit-jupiter-engine</artifactId>
             <scope>test</scope>
         </dependency>
-        <dependency>
-            <groupId>com.amazonaws</groupId>
-            <artifactId>aws-lambda-java-serialization</artifactId>
-            <scope>test</scope>
-        </dependency>
+
         <dependency>
             <groupId>org.apache.commons</groupId>
             <artifactId>commons-lang3</artifactId>

powertools-validation/src/main/java/software/amazon/lambda/powertools/validation/ValidationUtils.java

@@ -13,6 +13,7 @@
  */
 package software.amazon.lambda.powertools.validation;
 
+import java.io.ByteArrayOutputStream;
 import java.io.IOException;
 import java.io.InputStream;
 import java.util.Collections;
@@ -21,9 +22,12 @@
 import java.util.concurrent.ConcurrentHashMap;
 import java.util.stream.Collectors;
 
+import com.amazonaws.services.lambda.runtime.serialization.PojoSerializer;
+import com.amazonaws.services.lambda.runtime.serialization.events.LambdaEventSerializers;
 import com.fasterxml.jackson.core.JsonProcessingException;
 import com.fasterxml.jackson.databind.JsonNode;
 import com.fasterxml.jackson.databind.node.JsonNodeType;
+import com.fasterxml.jackson.databind.node.NullNode;
 import com.networknt.schema.JsonSchema;
 import com.networknt.schema.ValidationMessage;
 import io.burt.jmespath.Expression;
@@ -65,9 +69,15 @@ public static void validate(Object obj, JsonSchema jsonSchema, String envelope)
         }
         JsonNode subNode;
         try {
-            JsonNode jsonNode = ValidationConfig.get().getObjectMapper().valueToTree(obj);
+            PojoSerializer pojoSerializer = LambdaEventSerializers.serializerFor(obj.getClass(), ClassLoader.getSystemClassLoader());
+            ByteArrayOutputStream out = new ByteArrayOutputStream();
+            pojoSerializer.toJson(obj, out);
+            JsonNode jsonNode = ValidationConfig.get().getObjectMapper().readTree(out.toString("UTF-8"));
             Expression<JsonNode> expression = ValidationConfig.get().getJmesPath().compile(envelope);
             subNode = expression.search(jsonNode);
+            if (subNode == null || subNode instanceof NullNode) {
+                throw new ValidationException("Not found");
+            }
         } catch (Exception e) {
             throw new ValidationException("Cannot find envelope <"+envelope+"> in the object <"+obj+">", e);
         }

powertools-validation/src/test/java/software/amazon/lambda/powertools/validation/handlers/SQSWithCustomEnvelopeHandler.java

@@ -21,7 +21,7 @@
 public class SQSWithCustomEnvelopeHandler implements RequestHandler<SQSEvent, String> {
 
     @Override
-    @Validation(inboundSchema = "classpath:/schema_v7.json", envelope = "records[*].powertools_json(body).powertools_json(Message)")
+    @Validation(inboundSchema = "classpath:/schema_v7.json", envelope = "Records[*].powertools_json(body).powertools_json(Message)")
     public String handleRequest(SQSEvent input, Context context) {
         return "OK";
     }

powertools-validation/src/test/java/software/amazon/lambda/powertools/validation/handlers/SQSWithWrongEnvelopeHandler.java

@@ -0,0 +1,29 @@
+/*
+ * Copyright 2020 Amazon.com, Inc. or its affiliates.
+ * 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.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+package software.amazon.lambda.powertools.validation.handlers;
+
+import com.amazonaws.services.lambda.runtime.Context;
+import com.amazonaws.services.lambda.runtime.RequestHandler;
+import com.amazonaws.services.lambda.runtime.events.SQSEvent;
+import software.amazon.lambda.powertools.validation.Validation;
+
+public class SQSWithWrongEnvelopeHandler implements RequestHandler<SQSEvent, String> {
+
+    @Override
+    // real event contains Records with big R (https://docs.aws.amazon.com/lambda/latest/dg/with-sqs.html)
+    @Validation(inboundSchema = "classpath:/schema_v7.json", envelope = "records[*].powertools_json(body).powertools_json(Message)")
+    public String handleRequest(SQSEvent input, Context context) {
+        return "OK";
+    }
+}

powertools-validation/src/test/java/software/amazon/lambda/powertools/validation/internal/ValidationAspectTest.java

@@ -110,6 +110,15 @@ public void validate_SQS_CustomEnvelopeTakePrecedence() {
         assertThat(handler.handleRequest(event, context)).isEqualTo("OK");
     }
 
+    @Test
+    public void validate_SQS_WrongEnvelope_shouldThrowValidationException() {
+        PojoSerializer<SQSEvent> pojoSerializer = LambdaEventSerializers.serializerFor(SQSEvent.class, ClassLoader.getSystemClassLoader());
+        SQSEvent event = pojoSerializer.fromJson(this.getClass().getResourceAsStream("/sqs_message.json"));
+
+        SQSWithWrongEnvelopeHandler handler = new SQSWithWrongEnvelopeHandler();
+        assertThatExceptionOfType(ValidationException.class).isThrownBy(() -> handler.handleRequest(event, context));
+    }
+
     @Test
     public void validate_Kinesis() {
         PojoSerializer<KinesisEvent> pojoSerializer = LambdaEventSerializers.serializerFor(KinesisEvent.class, ClassLoader.getSystemClassLoader());