Use was-lambda-java-events library

build.gradle

@@ -12,8 +12,9 @@ repositories {
 }
 
 dependencies {
-    implementation 'com.amazonaws:aws-lambda-java-core:1.2.1'
     implementation 'uk.ac.gate:gate-core:8.6.1'
+    implementation 'com.amazonaws:aws-lambda-java-core:1.2.1'
+    implementation 'com.amazonaws:aws-lambda-java-events:2.2.9'
 
     runtimeOnly 'com.amazonaws:aws-lambda-java-log4j2:1.2.0'
 

src/main/java/co/zeroae/gate/App.java

@@ -2,6 +2,9 @@
 
 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 gate.*;
 import gate.creole.ExecutionException;
 import gate.creole.ResourceInstantiationException;
@@ -13,15 +16,14 @@
 import java.io.File;
 import java.net.URL;
 import java.util.HashMap;
-import java.util.Map;
 import java.util.Objects;
 
 /**
  * This class implements a GATE application using AWS Lambda.
  * It loads the application from the .gapp file defined by the GATE_APP_FILE environment variable.
  * For every lambda invocation, it runs the application and outputs the result in GateXML format.
  */
-public class App implements RequestHandler< Map<String, ?>, GatewayResponse> {
+public class App implements RequestHandler<APIGatewayProxyRequestEvent, APIGatewayProxyResponseEvent> {
     static {
         try {
             Gate.init();
@@ -33,34 +35,33 @@ public class App implements RequestHandler< Map<String, ?>, GatewayResponse> {
     private static final Logger logger = LogManager.getLogger(App.class);
     private static final CorpusController application = loadApplication();
 
-    public GatewayResponse handleRequest(final Map<String, ?> input, final Context context) {
-        final Map<String, String> headers = new HashMap<>();
-        headers.put("Content-Type", "text/plain");
+    public APIGatewayProxyResponseEvent handleRequest(APIGatewayProxyRequestEvent input, final Context context) {
+        final APIGatewayProxyResponseEvent response = new APIGatewayProxyResponseEvent()
+                .withHeaders(new HashMap<>());
+        response.getHeaders().put("Content-Type", "text/plain");
 
-        @SuppressWarnings("unchecked")
-        final Map<String, String> inputHeaders = (Map<String, String>) input.get("headers");
-        if (!inputHeaders.get("Content-Type").equalsIgnoreCase("text/plain")) {
-            return new GatewayResponse("We only support text/plain input.", headers, 400);
+        if (!input.getHeaders().get("Content-Type").equalsIgnoreCase("text/plain")) {
+            return response.withBody("We only support text/plain input.").withStatusCode(400);
         }
 
         try {
-            final Document doc = Factory.newDocument(input.get("body").toString());
+            final Document doc = Factory.newDocument(input.getBody());
             final Corpus corpus = application.getCorpus();
             corpus.add(doc);
             try {
                 application.execute();
-                headers.put("Content-Type", "application/xml");
-                return new GatewayResponse(doc.toXml(), headers, 200);
+                response.getHeaders().put("Content-Type", "application/xml");
+                return response.withBody(doc.toXml()).withStatusCode(200);
             } catch (ExecutionException e) {
                 logger.error(e);
-                return new GatewayResponse(e.getMessage(), headers, 500);
+                return response.withBody(e.getMessage()).withStatusCode(500);
             } finally {
                 corpus.clear();
                 Factory.deleteResource(doc);
             }
         } catch (ResourceInstantiationException e) {
             logger.warn(e);
-            return new GatewayResponse(e.getMessage(), headers, 400);
+            return response.withBody(e.getMessage()).withStatusCode(400);
         }
     }
 

src/test/java/co/zeroae/gate/AppTest.java

@@ -1,5 +1,7 @@
 package co.zeroae.gate;
 
+import com.amazonaws.services.lambda.runtime.events.APIGatewayProxyRequestEvent;
+import com.amazonaws.services.lambda.runtime.events.APIGatewayProxyResponseEvent;
 import org.junit.Test;
 
 import java.util.Collections;
@@ -13,25 +15,26 @@ public class AppTest {
   @Test
   public void successfulResponse() throws Exception {
     App app = withEnvironmentVariable("GATE_APP_NAME", "annie")
-      .execute(() -> new App());
+      .execute(App::new);
 
     // Create the Input
     final HashMap<String, String> input_headers = new HashMap<>();
     input_headers.put("Content-Type", "text/plain");
-    final HashMap<String, Object> input = new HashMap<>();
-    input.put("headers", Collections.unmodifiableMap(input_headers));
-    input.put("body", "This is a test. My name is LambdaTestFunction, and I just watched the T.V. show Wanda Vision.");
+    APIGatewayProxyRequestEvent input = new APIGatewayProxyRequestEvent()
+            .withHttpMethod("POST")
+            .withHeaders(Collections.unmodifiableMap(input_headers))
+            .withBody("This is a test. My name is LambdaTestFunction, and I just watched the T.V. show Wanda Vision.");
 
     // Context
     final TestContext context = new TestContext();
 
     // Invoke the App
-    final GatewayResponse result = app.handleRequest(Collections.unmodifiableMap(input), context);
+    final APIGatewayProxyResponseEvent result = app.handleRequest(input, context);
 
     // Assert Results
-    assertEquals(result.getStatusCode(), 200);
+    assertEquals(result.getStatusCode().intValue(), 200);
     assertEquals(result.getHeaders().get("Content-Type"), "application/xml");
-    String content = result.getBody();
+    final String content = result.getBody();
     assertNotNull(content);
     assertTrue(content.contains("GateDocument version=\"3\""));
   }