feat(v2): Validation failures return 400s

docs/utilities/validation.md

@@ -156,7 +156,10 @@ We support JSON schema version 4, 6, 7 and 201909 (from [jmespath-jackson librar
 
 `@Validation` annotation is used to validate either inbound events or functions' response.
 
-It will fail fast with `ValidationException` if an event or response doesn't conform with given JSON Schema.
+It will fail fast if an event or response doesn't conform with given JSON Schema. For most type of events a `ValidationException` will be thrown.
+For API gateway events associated with REST APIs and HTTP APIs -  `APIGatewayProxyRequestEvent` and `APIGatewayV2HTTPEvent` - the `@Validation` 
+annotation will build and return a custom 400 / "Bad Request" response, with a body containing the validation errors. This saves you from having
+to catch the validation exception and map it back to a meaningful user error yourself.
 
 While it is easier to specify a json schema file in the classpath (using the notation `"classpath:/path/to/schema.json"`), you can also provide a JSON String containing the schema.
 

examples/powertools-examples-validation/src/test/java/org/demo/validation/InboundValidationTest.java

@@ -53,13 +53,15 @@ public void shouldReturnOkStatusWhenInputIsValid() {
     }
 
     @Test
-    public void shouldThrowExceptionWhenRequestInInvalid() {
+    void shouldReturnBadRequestWhenRequestInInvalid() {
         String bodyWithMissedId = "{\n" +
                 "      \"name\": \"FooBar XY\",\n" +
                 "      \"price\": 258\n" +
                 "    }";
         APIGatewayProxyRequestEvent request = new APIGatewayProxyRequestEvent().withBody(bodyWithMissedId);
 
-        assertThrows(ValidationException.class, () -> inboundValidation.handleRequest(request, context));
+        APIGatewayProxyResponseEvent response = inboundValidation.handleRequest(request, context);
+
+        assertEquals(400, response.getStatusCode());
     }
 }

powertools-e2e-tests/handlers/pom.xml

@@ -32,6 +32,7 @@
         <module>metrics</module>
         <module>idempotency</module>
         <module>parameters</module>
+        <module>validation</module>
     </modules>
 
     <dependencyManagement>
@@ -79,6 +80,11 @@
                 <artifactId>powertools-batch</artifactId>
                 <version>${lambda.powertools.version}</version>
             </dependency>
+            <dependency>
+                <groupId>software.amazon.lambda</groupId>
+                <artifactId>powertools-validation</artifactId>
+                <version>${lambda.powertools.version}</version>
+            </dependency>
             <dependency>
                 <groupId>com.amazonaws</groupId>
                 <artifactId>aws-lambda-java-core</artifactId>

powertools-e2e-tests/handlers/validation/pom.xml

@@ -0,0 +1,60 @@
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+
+    <parent>
+        <groupId>software.amazon.lambda</groupId>
+        <artifactId>e2e-test-handlers-parent</artifactId>
+        <version>1.0.0</version>
+    </parent>
+
+    <artifactId>e2e-test-handler-validation</artifactId>
+    <packaging>jar</packaging>
+    <name>A Lambda function using Powertools for AWS Lambda (Java) validation</name>
+
+    <dependencies>
+        <dependency>
+            <groupId>software.amazon.lambda</groupId>
+            <artifactId>powertools-validation</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>com.amazonaws</groupId>
+            <artifactId>aws-lambda-java-events</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>org.aspectj</groupId>
+            <artifactId>aspectjrt</artifactId>
+        </dependency>
+    </dependencies>
+
+    <build>
+        <plugins>
+            <plugin>
+                <groupId>dev.aspectj</groupId>
+                <artifactId>aspectj-maven-plugin</artifactId>
+                <configuration>
+                    <source>${maven.compiler.source}</source>
+                    <target>${maven.compiler.target}</target>
+                    <complianceLevel>${maven.compiler.target}</complianceLevel>
+                    <aspectLibraries>
+                        <aspectLibrary>
+                            <groupId>software.amazon.lambda</groupId>
+                            <artifactId>powertools-validation</artifactId>
+                        </aspectLibrary>
+                    </aspectLibraries>
+                </configuration>
+                <executions>
+                    <execution>
+                        <goals>
+                            <goal>compile</goal>
+                        </goals>
+                    </execution>
+                </executions>
+            </plugin>
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-shade-plugin</artifactId>
+            </plugin>
+        </plugins>
+    </build>
+</project>

powertools-e2e-tests/handlers/validation/src/main/java/software/amazon/lambda/powertools/e2e/Function.java

@@ -0,0 +1,33 @@
+/*
+ * Copyright 2023 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.e2e;
+
+import com.amazonaws.services.lambda.runtime.Context;
+import com.amazonaws.services.lambda.runtime.RequestHandler;
+import com.amazonaws.services.lambda.runtime.events.APIGatewayProxyRequestEvent;
+import com.amazonaws.services.lambda.runtime.events.APIGatewayProxyResponseEvent;
+
+import software.amazon.lambda.powertools.validation.Validation;
+
+public class Function implements RequestHandler<APIGatewayProxyRequestEvent, APIGatewayProxyResponseEvent> {
+	@Validation(inboundSchema = "classpath:/validation/inbound_schema.json", outboundSchema = "classpath:/validation/outbound_schema.json")
+	public APIGatewayProxyResponseEvent handleRequest(APIGatewayProxyRequestEvent input, Context context) {
+		APIGatewayProxyResponseEvent response = new APIGatewayProxyResponseEvent();
+		response.setBody(input.getBody());
+		response.setStatusCode(200);
+		response.setIsBase64Encoded(false);
+		return response;
+	}
+}

powertools-e2e-tests/handlers/validation/src/main/resources/log4j2.xml

@@ -0,0 +1,16 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<Configuration>
+    <Appenders>
+        <Console name="JsonAppender" target="SYSTEM_OUT">
+            <JsonTemplateLayout eventTemplateUri="classpath:LambdaJsonLayout.json" />
+        </Console>
+    </Appenders>
+    <Loggers>
+        <Root level="INFO">
+            <AppenderRef ref="JsonAppender"/>
+        </Root>
+        <Logger name="JsonLogger" level="INFO" additivity="false">
+            <AppenderRef ref="JsonAppender"/>
+        </Logger>
+    </Loggers>
+</Configuration>

powertools-e2e-tests/handlers/validation/src/main/resources/validation/inbound_schema.json

@@ -0,0 +1,32 @@
+{
+  "$schema": "http://json-schema.org/draft-07/schema",
+  "$id": "http://example.com/product.json",
+  "type": "object",
+  "title": "Product schema",
+  "description": "JSON schema to validate Products",
+  "default": {},
+  "examples": [
+    {
+      "id": 43242,
+      "name": "FooBar XY",
+      "price": 258
+    }
+  ],
+  "required": [
+    "price"
+  ],
+  "properties": {
+    "price": {
+      "$id": "#/properties/price",
+      "type": "number",
+      "title": "Price of the product",
+      "description": "Positive price of the product",
+      "default": 0,
+      "exclusiveMinimum": 0,
+      "examples": [
+        258.99
+      ]
+    }
+  },
+  "additionalProperties": true
+}

powertools-e2e-tests/handlers/validation/src/main/resources/validation/outbound_schema.json

@@ -0,0 +1,32 @@
+{
+  "$schema": "http://json-schema.org/draft-07/schema",
+  "$id": "http://example.com/product.json",
+  "type": "object",
+  "title": "Product schema",
+  "description": "JSON schema to validate Products",
+  "default": {},
+  "examples": [
+    {
+      "id": 43242,
+      "name": "FooBar XY",
+      "price": 258
+    }
+  ],
+  "required": [
+    "price"
+  ],
+  "properties": {
+    "price": {
+      "$id": "#/properties/price",
+      "type": "number",
+      "title": "Price of the product",
+      "description": "Positive price of the product",
+      "default": 0,
+      "exclusiveMaximum": 1000,
+      "examples": [
+        258.99
+      ]
+    }
+  },
+  "additionalProperties": true
+}

powertools-e2e-tests/src/test/java/software/amazon/lambda/powertools/ValidationE2ET.java

@@ -0,0 +1,107 @@
+/*
+ * Copyright 2023 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;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static software.amazon.lambda.powertools.testutils.Infrastructure.FUNCTION_NAME_OUTPUT;
+import static software.amazon.lambda.powertools.testutils.lambda.LambdaInvoker.invokeFunction;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.nio.charset.StandardCharsets;
+import java.util.Map;
+import java.util.concurrent.TimeUnit;
+
+import org.apache.commons.io.IOUtils;
+import org.junit.jupiter.api.AfterAll;
+import org.junit.jupiter.api.BeforeAll;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.Timeout;
+
+import com.fasterxml.jackson.databind.JsonNode;
+import com.fasterxml.jackson.databind.ObjectMapper;
+
+import software.amazon.lambda.powertools.testutils.Infrastructure;
+import software.amazon.lambda.powertools.testutils.lambda.InvocationResult;
+
+class ValidationE2ET {
+
+	private static final ObjectMapper objectMapper = new ObjectMapper();
+
+	private static Infrastructure infrastructure;
+	private static String functionName;
+
+	@BeforeAll
+	@Timeout(value = 5, unit = TimeUnit.MINUTES)
+	public static void setup() {
+		infrastructure = Infrastructure.builder().testName(ValidationE2ET.class.getSimpleName())
+				.pathToFunction("validation").build();
+		Map<String, String> outputs = infrastructure.deploy();
+		functionName = outputs.get(FUNCTION_NAME_OUTPUT);
+	}
+
+	@AfterAll
+	public static void tearDown() {
+		if (infrastructure != null) {
+			infrastructure.destroy();
+		}
+	}
+
+	@Test
+	void test_validInboundApiGWEvent() throws IOException {
+		InputStream inputStream = this.getClass().getResourceAsStream("/validation/valid_api_gw_in_out_event.json");
+		String validEvent = IOUtils.toString(inputStream, StandardCharsets.UTF_8);
+
+		// WHEN
+		InvocationResult invocationResult = invokeFunction(functionName, validEvent);
+
+		// THEN
+		// invocation should pass validation and return 200
+		JsonNode validJsonNode = objectMapper.readTree(invocationResult.getResult());
+		assertThat(validJsonNode.get("statusCode").asInt()).isEqualTo(200);
+		assertThat(validJsonNode.get("body").asText()).isEqualTo("{\"price\": 150}");
+	}
+
+	@Test
+	void test_invalidInboundApiGWEvent() throws IOException {
+		InputStream inputStream = this.getClass().getResourceAsStream("/validation/invalid_api_gw_in_event.json");
+		String invalidEvent = IOUtils.toString(inputStream, StandardCharsets.UTF_8);
+
+		// WHEN
+		InvocationResult invocationResult = invokeFunction(functionName, invalidEvent);
+
+		// THEN
+		// invocation should fail inbound validation and return 400
+		JsonNode validJsonNode = objectMapper.readTree(invocationResult.getResult());
+		assertThat(validJsonNode.get("statusCode").asInt()).isEqualTo(400);
+		assertThat(validJsonNode.get("body").asText()).contains("$.price: is missing but it is required");
+	}
+
+	@Test
+	void test_invalidOutboundApiGWEvent() throws IOException {
+		InputStream inputStream = this.getClass().getResourceAsStream("/validation/invalid_api_gw_out_event.json");
+		String invalidEvent = IOUtils.toString(inputStream, StandardCharsets.UTF_8);
+
+		// WHEN
+		InvocationResult invocationResult = invokeFunction(functionName, invalidEvent);
+
+		// THEN
+		// invocation should fail outbound validation and return 400
+		JsonNode validJsonNode = objectMapper.readTree(invocationResult.getResult());
+		assertThat(validJsonNode.get("statusCode").asInt()).isEqualTo(400);
+		assertThat(validJsonNode.get("body").asText())
+				.contains("$.price: must have an exclusive maximum value of 1000");
+	}
+}