Modernize circuit breaker examples

circuit-breaker-examples/src/main/java/io/vertx/example/circuit/breaker/Client.java

@@ -4,51 +4,56 @@
 import io.vertx.circuitbreaker.CircuitBreakerOptions;
 import io.vertx.core.AbstractVerticle;
 import io.vertx.core.Future;
+import io.vertx.core.VerticleBase;
 import io.vertx.core.buffer.Buffer;
+import io.vertx.core.http.HttpClientAgent;
 import io.vertx.core.http.HttpMethod;
+import io.vertx.core.http.HttpResponseExpectation;
 import io.vertx.launcher.application.VertxApplication;
 
 /**
  * @author <a href="[email protected]">Pahan</a>
  */
 
-public class Client extends AbstractVerticle {
+public class Client extends VerticleBase {
 
   public static void main(String[] args) {
     VertxApplication.main(new String[]{Client.class.getName()});
   }
 
+  private HttpClientAgent httpClient;
+  private CircuitBreaker breaker;
+
   @Override
-  public void start() {
+  public Future<?> start() {
     CircuitBreakerOptions options = new CircuitBreakerOptions()
       .setMaxFailures(5)
       .setTimeout(5000)
       .setFallbackOnFailure(true);
 
-    CircuitBreaker breaker =
+    httpClient = vertx.createHttpClient();
+    breaker =
       CircuitBreaker.create("my-circuit-breaker", vertx, options)
         .openHandler(v -> {
           System.out.println("Circuit opened");
         }).closeHandler(v -> {
-        System.out.println("Circuit closed");
-      });
-
-    breaker.executeWithFallback(promise -> {
-      vertx.createHttpClient().request(HttpMethod.GET, 8080, "localhost", "/").compose(req -> {
-        return req.send().compose(resp -> {
-          if (resp.statusCode() != 200) {
-            return Future.failedFuture("HTTP error");
-          } else {
-            return resp.body().map(Buffer::toString);
-          }
+          System.out.println("Circuit closed");
         });
-      }).onComplete(promise);
-    }, v -> {
-      // Executed when the circuit is opened
-      return "Hello (fallback)";
-    }).onComplete(ar -> {
-      // Do something with the result
-      System.out.println("Result: " + ar.result());
-    });
+
+    return breaker
+      .executeWithFallback(() -> httpClient
+        .request(HttpMethod.GET, 8080, "localhost", "/").
+        compose(req -> req
+          .send()
+          .expecting(HttpResponseExpectation.SC_OK)
+          .compose(resp -> resp.body())
+          .map(body -> body.toString())), v -> {
+        // Executed when the circuit is opened
+        return "Hello (fallback)";
+      })
+      .onSuccess(res -> {
+        // Do something with the result
+        System.out.println("Result: " + res);
+      });
   }
 }

circuit-breaker-examples/src/main/java/io/vertx/example/circuit/breaker/Server.java

@@ -1,17 +1,19 @@
 package io.vertx.example.circuit.breaker;
 
-import io.vertx.core.AbstractVerticle;
+import io.vertx.core.Future;
+import io.vertx.core.VerticleBase;
 import io.vertx.launcher.application.VertxApplication;
 
-public class Server extends AbstractVerticle {
+public class Server extends VerticleBase {
 
   public static void main(String[] args) {
     VertxApplication.main(new String[]{Server.class.getName()});
   }
 
   @Override
-  public void start() {
-    vertx.createHttpServer()
+  public Future<?> start() {
+    return vertx
+      .createHttpServer()
     .requestHandler(req -> req.response().end("Bonjour"))
     .listen(8080);
   }