added implementation

1 files changed, 89 insertions, 4 deletions

diff --git a/src/main/java/eu/ortlepp/notificationsender/NotificationHandler.java b/src/main/java/eu/ortlepp/notificationsender/NotificationHandler.java
index 43e1aa9..17b4a46 100644
--- a/src/main/java/eu/ortlepp/notificationsender/NotificationHandler.java
+++ b/src/main/java/eu/ortlepp/notificationsender/NotificationHandler.java
@@ -1,12 +1,97 @@
 package eu.ortlepp.notificationsender;
 
 import com.amazonaws.services.lambda.runtime.Context;
+import com.amazonaws.services.lambda.runtime.LambdaLogger;
 import com.amazonaws.services.lambda.runtime.RequestHandler;
+import com.fasterxml.jackson.core.JsonProcessingException;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import eu.ortlepp.notificationsender.model.Notifications;
+import eu.ortlepp.notificationsender.model.Response;
+import eu.ortlepp.notificationsender.model.Status;
+import eu.ortlepp.notificationsender.service.NotificationSender;
+import eu.ortlepp.notificationsender.service.SnsNotificationSender;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.List;
+import java.util.Map;
 
-public class NotificationHandler implements RequestHandler<String, String> {
+/**
+ * AWS Lambda implementation.
+ */
+public class NotificationHandler implements RequestHandler<Map<String, Object>, Response> {
 
-  public String handleRequest(String event, Context context) {
-    return event.toLowerCase();
+  private LambdaLogger logger;
+
+  private NotificationSender sender;
+
+
+  /**
+   * Standard constructor for AWS runtime. Uses default NotificationSender implementation.
+   */
+  public NotificationHandler() {
+    this.sender = null;
+  }
+
+
+  /**
+   * Constructor with custom NotificationSender implementation. Mainly for testing purposes.
+   *
+   * @param sender A custom NotificationSender
+   */
+  public NotificationHandler(final NotificationSender sender) {
+    this.sender = sender;
+  }
+
+
+  /**
+   * Constructor with custom NotificationSender and Context implementation.
+   * Mainly for testing purposes.
+   *
+   * @param sender A custom NotificationSender
+   * @param context A custom Context (to initialize the build-in logger)
+   */
+  public NotificationHandler(final NotificationSender sender, final Context context) {
+    this.sender = sender;
+    this.logger = context.getLogger();
+  }
+
+
+  /**
+   * The AWS Lambda handler; executes the Lambda functionality.
+   *
+   * @param event The incoming event which triggered the Lambda
+   * @param context The context of the Lambda execution
+   * @return The final status of the execution
+   */
+  public Response handleRequest(final Map<String, Object> event, final Context context) {
+    logger = context.getLogger();
+    if (sender == null) {
+      sender = new SnsNotificationSender(logger);
+    }
+
+    List<String> notifications = extractNotifications(event.get("body"));
+    if (!notifications.isEmpty() && sender.sendNotifications(notifications)) {
+      return new Response(Status.SUCCESS);
+    }
+    return new Response(Status.FAILED);
+  }
+
+
+  /**
+   * Extract the notifications from the input JSON.
+   *
+   * @param body The input JSON
+   * @return The extracted messages; empty list if an error occurred while parsing the JSON
+   */
+  protected List<String> extractNotifications(final Object body) {
+    try {
+      Notifications notifications =
+          new ObjectMapper().readValue(body.toString(), Notifications.class);
+      return Arrays.asList(notifications.messages());
+    } catch (JsonProcessingException ex) {
+      logger.log("parsing input JSON failed : " + ex.getMessage());
+      return new ArrayList<>();
+    }
   }
 
-}
\ No newline at end of file
+}