set max 3 retries for active failover redirects (#412)

Author: rashtao

src/main/java/com/arangodb/async/internal/velocystream/VstCommunicationAsync.java

@@ -56,6 +56,11 @@ private VstCommunicationAsync(final HostHandler hostHandler, final Integer timeo
 
     @Override
     protected CompletableFuture<Response> execute(final Request request, final VstConnectionAsync connection) {
+        return execute(request, connection, 0);
+    }
+
+    @Override
+    protected CompletableFuture<Response> execute(final Request request, final VstConnectionAsync connection, final int attemptCount) {
         final CompletableFuture<Response> rfuture = new CompletableFuture<>();
         try {
             final Message message = createMessage(request);
@@ -73,11 +78,15 @@ protected CompletableFuture<Response> execute(final Request request, final VstCo
                     try {
                         checkError(response);
                     } catch (final ArangoDBRedirectException e) {
+                        if (attemptCount >= 3) {
+                            rfuture.completeExceptionally(e);
+                            return;
+                        }
                         final String location = e.getLocation();
                         final HostDescription redirectHost = HostUtils.createFromLocation(location);
                         hostHandler.closeCurrentOnError();
                         hostHandler.fail();
-                        execute(request, new HostHandle().setHost(redirectHost))
+                        execute(request, new HostHandle().setHost(redirectHost), attemptCount + 1)
                                 .whenComplete((v, err) -> {
                                     if (v != null) {
                                         rfuture.complete(v);

src/main/java/com/arangodb/internal/http/HttpCommunication.java

@@ -72,6 +72,10 @@ public void close() throws IOException {
     }
 
     public Response execute(final Request request, final HostHandle hostHandle) throws ArangoDBException, IOException {
+        return execute(request, hostHandle, 0);
+    }
+
+    private Response execute(final Request request, final HostHandle hostHandle, final int attemptCount) throws ArangoDBException, IOException {
         final AccessType accessType = RequestUtils.determineAccessType(request);
         Host host = hostHandler.get(hostHandle, accessType);
         try {
@@ -99,12 +103,12 @@ public Response execute(final Request request, final HostHandle hostHandle) thro
                 }
             }
         } catch (final ArangoDBException e) {
-            if (e instanceof ArangoDBRedirectException) {
+            if (e instanceof ArangoDBRedirectException && attemptCount < 3) {
                 final String location = ((ArangoDBRedirectException) e).getLocation();
                 final HostDescription redirectHost = HostUtils.createFromLocation(location);
                 hostHandler.closeCurrentOnError();
                 hostHandler.fail();
-                return execute(request, new HostHandle().setHost(redirectHost));
+                return execute(request, new HostHandle().setHost(redirectHost), attemptCount + 1);
             } else {
                 throw e;
             }

src/main/java/com/arangodb/internal/velocystream/VstCommunication.java

@@ -138,12 +138,18 @@ public void close() throws IOException {
     }
 
     public R execute(final Request request, final HostHandle hostHandle) throws ArangoDBException {
+        return execute(request, hostHandle, 0);
+    }
+
+    protected R execute(final Request request, final HostHandle hostHandle, final int attemptCount) throws ArangoDBException {
         final C connection = connect(hostHandle, RequestUtils.determineAccessType(request));
-        return execute(request, connection);
+        return execute(request, connection, attemptCount);
     }
 
     protected abstract R execute(final Request request, C connection) throws ArangoDBException;
 
+    protected abstract R execute(final Request request, C connection, final int attemptCount) throws ArangoDBException;
+
     protected void checkError(final Response response) throws ArangoDBException {
         ResponseUtils.checkError(util, response);
     }

src/main/java/com/arangodb/internal/velocystream/VstCommunicationSync.java

@@ -123,6 +123,11 @@ protected VstCommunicationSync(final HostHandler hostHandler, final Integer time
 
     @Override
     protected Response execute(final Request request, final VstConnectionSync connection) throws ArangoDBException {
+        return execute(request, connection, 0);
+    }
+
+    @Override
+    protected Response execute(final Request request, final VstConnectionSync connection, final int attemptCount) throws ArangoDBException {
         try {
             final Message requestMessage = createMessage(request);
             final Message responseMessage = send(requestMessage, connection);
@@ -132,11 +137,14 @@ protected Response execute(final Request request, final VstConnectionSync connec
         } catch (final VPackParserException e) {
             throw new ArangoDBException(e);
         } catch (final ArangoDBRedirectException e) {
+            if (attemptCount >= 3) {
+                throw e;
+            }
             final String location = e.getLocation();
             final HostDescription redirectHost = HostUtils.createFromLocation(location);
             hostHandler.closeCurrentOnError();
             hostHandler.fail();
-            return execute(request, new HostHandle().setHost(redirectHost));
+            return execute(request, new HostHandle().setHost(redirectHost), attemptCount + 1);
         }
     }