Fix for Issue iluwatar#549 : Add Fallbacks in Aggregator Service (iluwatar#971)

jarpit96 · iluwatar · commit 1d4a7681e2d8 · 2019-11-01T20:01:30.000+02:00
* Fix for Issue#iluwatar#549 Catch ClientProtocolException and Update Error Logs * Fix indentation, checkstyle errors * Fix for Issue iluwatar#549 Add fallbacks in Aggregator service when other microservices fail * Make ProductInventoryClientImpl return null instead of zero in case of failure
diff --git a/aggregator-microservices/aggregator-service/src/main/java/com/iluwatar/aggregator/microservices/Aggregator.java b/aggregator-microservices/aggregator-service/src/main/java/com/iluwatar/aggregator/microservices/Aggregator.java
@@ -51,9 +51,23 @@ public class Aggregator {
    */
   @RequestMapping(path = "/product", method = RequestMethod.GET)
   public Product getProduct() {
+
     var product = new Product();
-    product.setTitle(informationClient.getProductTitle());
-    product.setProductInventories(inventoryClient.getProductInventories());
+    String productTitle = informationClient.getProductTitle();
+    Integer productInventory = inventoryClient.getProductInventories();
+
+    if (productTitle != null) {
+      product.setTitle(productTitle);
+    } else {
+      product.setTitle("Error: Fetching Product Title Failed"); //Fallback to error message
+    }
+
+    if (productInventory != null) {
+      product.setProductInventories(productInventory);
+    } else {
+      product.setProductInventories(-1); //Fallback to default error inventory
+    }
+
     return product;
   }
 
diff --git a/aggregator-microservices/aggregator-service/src/main/java/com/iluwatar/aggregator/microservices/ProductInventoryClient.java b/aggregator-microservices/aggregator-service/src/main/java/com/iluwatar/aggregator/microservices/ProductInventoryClient.java
@@ -28,5 +28,5 @@
  */
 public interface ProductInventoryClient {
 
-  int getProductInventories();
+  Integer getProductInventories();
 }
diff --git a/aggregator-microservices/aggregator-service/src/main/java/com/iluwatar/aggregator/microservices/ProductInventoryClientImpl.java b/aggregator-microservices/aggregator-service/src/main/java/com/iluwatar/aggregator/microservices/ProductInventoryClientImpl.java
@@ -42,8 +42,8 @@ public class ProductInventoryClientImpl implements ProductInventoryClient {
   private static final Logger LOGGER = LoggerFactory.getLogger(ProductInventoryClientImpl.class);
 
   @Override
-  public int getProductInventories() {
-    var response = "0";
+  public Integer getProductInventories() {
+    var response = "";
 
     var request = HttpRequest.newBuilder().GET().uri(URI.create("http://localhost:51516/inventories")).build();
     var client = HttpClient.newHttpClient();
@@ -55,6 +55,10 @@ public int getProductInventories() {
     } catch (InterruptedException ie) {
       LOGGER.error("InterruptedException Occurred", ie);
     }
-    return Integer.parseInt(response);
+    if("".equalsIgnoreCase(response)) {
+        return null;
+    } else {
+        return Integer.parseInt(response);
+    }
   }
 }

Original file line number	Diff line number	Diff line change
`@@ -28,5 +28,5 @@`
`28`	`28`	`*/`
`29`	`29`	`public interface ProductInventoryClient {`
`30`	`30`
`31`		`- int getProductInventories();`
	`31`	`+ Integer getProductInventories();`
`32`	`32`	`}`