Merge branch 'pagejep/generic-serdes-durable-config' into 'main'

feat(config): Customizable DurableConfig for setting default configuration

See merge request mxschell/aws-durable-execution-sdk-java!13

Author: phipag

examples/pom.xml

@@ -30,6 +30,12 @@
             <artifactId>aws-lambda-java-core</artifactId>
         </dependency>
 
+        <!-- AWS SDK Apache HTTP Client -->
+        <dependency>
+            <groupId>software.amazon.awssdk</groupId>
+            <artifactId>apache-client</artifactId>
+        </dependency>
+        
         <!-- SLF4J Simple Logger -->
         <dependency>
             <groupId>org.slf4j</groupId>

examples/src/main/java/com/amazonaws/lambda/durable/examples/CustomConfigExample.java

@@ -0,0 +1,144 @@
+// Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
+// SPDX-License-Identifier: Apache-2.0
+package com.amazonaws.lambda.durable.examples;
+
+import com.amazonaws.lambda.durable.DurableConfig;
+import com.amazonaws.lambda.durable.DurableContext;
+import com.amazonaws.lambda.durable.DurableHandler;
+import com.amazonaws.lambda.durable.TypeToken;
+import com.amazonaws.lambda.durable.client.LambdaDurableFunctionsClient;
+import com.amazonaws.lambda.durable.serde.SerDes;
+import com.fasterxml.jackson.core.JsonProcessingException;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.fasterxml.jackson.databind.PropertyNamingStrategies;
+import java.io.IOException;
+import java.time.Duration;
+import software.amazon.awssdk.auth.credentials.EnvironmentVariableCredentialsProvider;
+import software.amazon.awssdk.core.SdkSystemSetting;
+import software.amazon.awssdk.http.apache.ApacheHttpClient;
+import software.amazon.awssdk.regions.Region;
+import software.amazon.awssdk.services.lambda.LambdaClient;
+
+/**
+ * Example demonstrating custom configuration with both custom HTTP client and custom SerDes. Shows how to configure a
+ * custom Apache HTTP client for the Lambda client while maintaining automatic credentials detection and region
+ * fallback, plus a custom SerDes with snake_case naming.
+ *
+ * <p>This example demonstrates:
+ *
+ * <ul>
+ *   <li>Custom Apache HTTP client configuration for improved performance
+ *   <li>Automatic region detection with fallback to us-east-1 for testing environments
+ *   <li>Environment variable credentials provider
+ *   <li>Custom SerDes with snake_case property naming
+ * </ul>
+ */
+public class CustomConfigExample extends DurableHandler<String, String> {
+
+    @Override
+    protected DurableConfig createConfiguration() {
+        // Configure custom Apache HTTP client for better performance
+        var httpClient = ApacheHttpClient.builder()
+                .maxConnections(50)
+                .connectionTimeout(Duration.ofSeconds(30))
+                .socketTimeout(Duration.ofSeconds(60))
+                .build();
+
+        // Get region with fallback to us-east-1 if AWS_REGION not set
+        // This prevents initialization failures in testing environments
+        var region = System.getenv(SdkSystemSetting.AWS_REGION.environmentVariable());
+        if (region == null || region.isEmpty()) {
+            region = "us-east-1";
+        }
+
+        // Create Lambda client with custom HTTP client
+        // Uses automatic credentials detection and region fallback
+        var lambdaClient = LambdaClient.builder()
+                .httpClient(httpClient)
+                .credentialsProvider(EnvironmentVariableCredentialsProvider.create())
+                .region(Region.of(region))
+                .build();
+
+        // Wrap the Lambda client with LambdaDurableFunctionsClient
+        var durableClient = new LambdaDurableFunctionsClient(lambdaClient);
+
+        // Create custom SerDes with snake_case naming
+        var customSerDes = new SnakeCaseSerDes();
+
+        return DurableConfig.builder()
+                .withDurableExecutionClient(durableClient)
+                .withSerDes(customSerDes)
+                .build();
+    }
+
+    @Override
+    public String handleRequest(String input, DurableContext context) {
+        // Step 1: Create a custom object with camelCase fields to demonstrate snake_case serialization
+        var customObject = context.step(
+                "create-custom-object",
+                CustomData.class,
+                () -> new CustomData("user123", "John Doe", 25, "john.doe@example.com"));
+
+        return "Created custom object: " + customObject.userId + ", " + customObject.fullName + ", "
+                + customObject.userAge + ", " + customObject.emailAddress;
+    }
+
+    /**
+     * Custom data class with camelCase field names to demonstrate snake_case serialization. The SerDes will convert
+     * these field names to snake_case in the JSON output.
+     */
+    public static class CustomData {
+        public String userId;
+        public String fullName;
+        public int userAge;
+        public String emailAddress;
+
+        public CustomData() {}
+
+        public CustomData(String userId, String fullName, int userAge, String emailAddress) {
+            this.userId = userId;
+            this.fullName = fullName;
+            this.userAge = userAge;
+            this.emailAddress = emailAddress;
+        }
+    }
+
+    /**
+     * Custom SerDes implementation using snake_case property naming. Demonstrates how to provide custom serialization
+     * behavior.
+     */
+    private static class SnakeCaseSerDes implements SerDes {
+        private final ObjectMapper objectMapper;
+
+        public SnakeCaseSerDes() {
+            this.objectMapper = new ObjectMapper().setPropertyNamingStrategy(PropertyNamingStrategies.SNAKE_CASE);
+        }
+
+        @Override
+        public String serialize(Object obj) {
+            try {
+                return objectMapper.writeValueAsString(obj);
+            } catch (JsonProcessingException e) {
+                throw new RuntimeException("Serialization failed", e);
+            }
+        }
+
+        @Override
+        public <T> T deserialize(String json, Class<T> clazz) {
+            try {
+                return objectMapper.readValue(json, clazz);
+            } catch (IOException e) {
+                throw new RuntimeException("Deserialization failed", e);
+            }
+        }
+
+        @Override
+        public <T> T deserialize(String json, TypeToken<T> typeToken) {
+            try {
+                return objectMapper.readValue(json, objectMapper.constructType(typeToken.getType()));
+            } catch (IOException e) {
+                throw new RuntimeException("Deserialization failed", e);
+            }
+        }
+    }
+}

examples/src/main/java/com/amazonaws/lambda/durable/examples/GenericTypesExample.java

@@ -48,7 +48,7 @@ public Output(List<String> items, Map<String, Integer> counts, Map<String, List<
     }
 
     @Override
-    protected Output handleRequest(Input input, DurableContext context) {
+    public Output handleRequest(Input input, DurableContext context) {
         logger.info("Starting generic types example for user: {}", input.userId);
 
         // Step 1: Fetch a list of items (List<String>)

examples/src/main/java/com/amazonaws/lambda/durable/examples/RetryExample.java

@@ -29,7 +29,7 @@ public class RetryExample extends DurableHandler<Object, String> {
     private Instant startTime;
 
     @Override
-    protected String handleRequest(Object input, DurableContext context) {
+    public String handleRequest(Object input, DurableContext context) {
         // Step 1: Record start time
         startTime = context.step("record-start-time", Instant.class, Instant::now);
         logger.info("Recorded start time: {}", startTime);

examples/src/main/java/com/amazonaws/lambda/durable/examples/RetryInProcessExample.java

@@ -31,7 +31,7 @@ public class RetryInProcessExample extends DurableHandler<Object, String> {
     private final AtomicInteger attemptCount = new AtomicInteger(0);
 
     @Override
-    protected String handleRequest(Object input, DurableContext context) {
+    public String handleRequest(Object input, DurableContext context) {
         logger.info("Starting retry in-process example");
 
         // Start async step that will fail and retry

examples/src/main/java/com/amazonaws/lambda/durable/examples/SimpleStepExample.java

@@ -19,7 +19,7 @@
 public class SimpleStepExample extends DurableHandler<GreetingRequest, String> {
 
     @Override
-    protected String handleRequest(GreetingRequest input, DurableContext context) {
+    public String handleRequest(GreetingRequest input, DurableContext context) {
         // Step 1: Create greeting
         var greeting = context.step("create-greeting", String.class, () -> "Hello, " + input.getName());
 

examples/src/main/java/com/amazonaws/lambda/durable/examples/WaitAtLeastExample.java

@@ -28,7 +28,7 @@ public class WaitAtLeastExample extends DurableHandler<GreetingRequest, String>
     private static final Logger logger = LoggerFactory.getLogger(WaitAtLeastExample.class);
 
     @Override
-    protected String handleRequest(GreetingRequest input, DurableContext context) {
+    public String handleRequest(GreetingRequest input, DurableContext context) {
         logger.info("Starting concurrent step + wait example for: {}", input.getName());
 
         // Start an async step that takes 2 seconds

examples/src/main/java/com/amazonaws/lambda/durable/examples/WaitAtLeastInProcessExample.java

@@ -28,7 +28,7 @@ public class WaitAtLeastInProcessExample extends DurableHandler<GreetingRequest,
     private static final Logger logger = LoggerFactory.getLogger(WaitAtLeastInProcessExample.class);
 
     @Override
-    protected String handleRequest(GreetingRequest input, DurableContext context) {
+    public String handleRequest(GreetingRequest input, DurableContext context) {
         logger.info("Starting concurrent step + wait example for: {}", input.getName());
 
         // Start an async step that takes 10 seconds

examples/src/main/java/com/amazonaws/lambda/durable/examples/WaitExample.java

@@ -22,7 +22,7 @@
 public class WaitExample extends DurableHandler<GreetingRequest, String> {
 
     @Override
-    protected String handleRequest(GreetingRequest input, DurableContext context) {
+    public String handleRequest(GreetingRequest input, DurableContext context) {
         // Step 1: Start processing
         var started = context.step("start-processing", String.class, () -> "Started processing for " + input.getName());
 

examples/src/test/java/com/amazonaws/lambda/durable/examples/CloudBasedIntegrationTest.java

@@ -194,4 +194,33 @@ void testGenericTypesExample() {
         assertNotNull(runner.getOperation("count-by-category"));
         assertNotNull(runner.getOperation("fetch-categories"));
     }
+
+    @Test
+    void testCustomConfigExample() {
+        var runner = CloudDurableTestRunner.create(arn("custom-config-example"), String.class, String.class);
+        var result = runner.run("test-input");
+
+        assertEquals(ExecutionStatus.SUCCEEDED, result.getStatus());
+
+        var finalResult = result.getResult(String.class);
+        assertNotNull(finalResult);
+        assertTrue(finalResult.contains("Created custom object"));
+        assertTrue(finalResult.contains("user123"));
+        assertTrue(finalResult.contains("John Doe"));
+        assertTrue(finalResult.contains("25"));
+        assertTrue(finalResult.contains("john.doe@example.com"));
+
+        // Verify the step operation was executed
+        var createObjectOp = runner.getOperation("create-custom-object");
+        assertNotNull(createObjectOp);
+        assertEquals("create-custom-object", createObjectOp.getName());
+
+        // The step result should contain the serialized JSON with snake_case
+        var stepResult = createObjectOp.getStepDetails().result();
+        assertNotNull(stepResult);
+        assertTrue(stepResult.contains("user_id"));
+        assertTrue(stepResult.contains("full_name"));
+        assertTrue(stepResult.contains("user_age"));
+        assertTrue(stepResult.contains("email_address"));
+    }
 }