context: remove detach from Context

- fix #3791
- handle undertow dispatch/detach internally

Author: jknack

jooby/src/main/java/io/jooby/Context.java

@@ -1010,18 +1010,6 @@ default Value lookup(String name) {
    */
   Context dispatch(@NonNull Executor executor, @NonNull Runnable action);
 
-  /**
-   * Tells context that response will be generated form a different thread. This operation is
-   * similar to {@link #dispatch(Runnable)} except there is no thread dispatching here.
-   *
-   * <p>This operation integrates easily with third-party libraries like rxJava or others.
-   *
-   * @param next Application code.
-   * @return This context.
-   * @throws Exception When detach operation fails.
-   */
-  Context detach(@NonNull Route.Handler next) throws Exception;
-
   /**
    * Perform a websocket handsahke and upgrade a HTTP GET into a websocket protocol.
    *

jooby/src/main/java/io/jooby/ForwardingContext.java

@@ -1044,12 +1044,6 @@ public Context dispatch(@NonNull Executor executor, @NonNull Runnable action) {
     return this;
   }
 
-  @Override
-  public Context detach(@NonNull Route.Handler next) throws Exception {
-    ctx.detach(next);
-    return this;
-  }
-
   @Override
   public Context upgrade(@NonNull WebSocket.Initializer handler) {
     ctx.upgrade(handler);

jooby/src/main/java/io/jooby/Route.java

@@ -106,6 +106,9 @@ public void setRoute(Route route) {
     }
   }
 
+  /** Marker interface for reactive responses. */
+  public interface Reactive extends Filter {}
+
   /**
    * Decorates a handler and run logic before handler is executed.
    *
@@ -699,7 +702,7 @@ public Route setEncoder(@NonNull MessageEncoder encoder) {
    *
    * @return Truth when route is non-blocking. False otherwise or <code>null</code> otherwise.
    */
-  @NonNull public boolean isNonBlocking() {
+  public boolean isNonBlocking() {
     return nonBlocking == Boolean.TRUE;
   }
 

jooby/src/main/java/io/jooby/internal/Pipeline.java

@@ -6,7 +6,6 @@
 package io.jooby.internal;
 
 import static io.jooby.internal.handler.DefaultHandler.DEFAULT;
-import static io.jooby.internal.handler.DetachHandler.DETACH;
 import static io.jooby.internal.handler.WorkerHandler.WORKER;
 
 import java.util.concurrent.Executor;
@@ -20,19 +19,11 @@
 public class Pipeline {
 
   public static Handler build(
-      boolean requiresDetach,
-      Route route,
-      ExecutionMode mode,
-      Executor executor,
-      ContextInitializer initializer) {
+      Route route, ExecutionMode mode, Executor executor, ContextInitializer initializer) {
     // Set default wrapper and blocking mode
     if (!route.isNonBlockingSet()) {
       route.setNonBlocking(isDefaultNonblocking(executor, mode));
     }
-    Route.Filter wrapper = DEFAULT;
-    if (requiresDetach && route.isNonBlocking()) {
-      wrapper = DETACH.then(wrapper);
-    }
 
     // Non-Blocking? Split pipeline Head+Handler let reactive call After pipeline
     Handler pipeline;
@@ -43,7 +34,7 @@ public static Handler build(
       pipeline = route.getPipeline();
     }
     return dispatchHandler(
-        mode, executor, decorate(initializer, wrapper.then(pipeline)), route.isNonBlocking());
+        mode, executor, decorate(initializer, DEFAULT.then(pipeline)), route.isNonBlocking());
   }
 
   private static boolean isDefaultNonblocking(Executor executor, ExecutionMode mode) {

jooby/src/main/java/io/jooby/internal/RouterImpl.java

@@ -592,10 +592,8 @@ public void initialize() {
             prependMediaType(route.getConsumes(), route.getFilter(), Route.SUPPORT_MEDIA_TYPE));
         route.setFilter(prependMediaType(route.getProduces(), route.getFilter(), Route.ACCEPT));
       }
-      boolean requiresDetach = server.getName().equals("undertow");
       Route.Handler pipeline =
-          Pipeline.build(
-              requiresDetach, route, forceMode(route, mode), executor, postDispatchInitializer);
+          Pipeline.build(route, forceMode(route, mode), executor, postDispatchInitializer);
       route.setPipeline(pipeline);
       /** Final render */
       route.setEncoder(encoder);

jooby/src/main/java/io/jooby/internal/handler/ConcurrentHandler.java

@@ -15,7 +15,7 @@
 import edu.umd.cs.findbugs.annotations.NonNull;
 import io.jooby.Route;
 
-public class ConcurrentHandler implements Route.Filter {
+public class ConcurrentHandler implements Route.Reactive {
 
   @NonNull @Override
   public Route.Handler apply(@NonNull Route.Handler next) {
@@ -38,11 +38,11 @@ public Route.Handler apply(@NonNull Route.Handler next) {
                   after.apply(ctx, value, unwrap((Throwable) x));
                 }
                 if (x != null) {
-                  Throwable exception = unwrap((Throwable) x);
+                  Throwable exception = unwrap(x);
                   ctx.sendError(exception);
                 } else {
                   // See https://github.com/jooby-project/jooby/issues/3486
-                  if (!ctx.isResponseStarted() && value != ctx) {
+                  if (!ctx.isResponseStarted() && value != ctx && value != null) {
                     ctx.render(value);
                   }
                 }

jooby/src/main/java/io/jooby/internal/handler/DetachHandler.java

@@ -370,12 +370,6 @@ public Context dispatch(@NonNull Executor executor, @NonNull Runnable action) {
     return this;
   }
 
-  @NonNull @Override
-  public Context detach(@NonNull Route.Handler next) throws Exception {
-    next.apply(this);
-    return this;
-  }
-
   @NonNull @Override
   public Context upgrade(@NonNull WebSocket.Initializer handler) {
     try {

modules/jooby-jetty/src/main/java/io/jooby/internal/jetty/JettyContext.java

@@ -23,7 +23,7 @@
 public class Mutiny {
 
   private static final Route.Filter MUTINY =
-      new Route.Filter() {
+      new Route.Reactive() {
 
         private void after(Context ctx, Object value, Throwable failure) {
           Route.After after = ctx.getRoute().getAfter();

modules/jooby-mutiny/src/main/java/io/jooby/mutiny/Mutiny.java

@@ -253,12 +253,6 @@ public Context dispatch(Executor executor, Runnable action) {
     return this;
   }
 
-  @NonNull @Override
-  public Context detach(@NonNull Route.Handler next) throws Exception {
-    next.apply(this);
-    return this;
-  }
-
   @NonNull @Override
   public QueryString query() {
     if (query == null) {