[#4873] Support for SSE interface RPC calls

common/common-rest/src/main/java/org/apache/servicecomb/common/rest/filter/inner/ServerRestArgsFilter.java

@@ -113,7 +113,7 @@ public static boolean isServerSendEvent(Response response) {
 
   private static CompletableFuture<Void> writeServerSendEvent(Invocation invocation, Response response,
       ProduceProcessor produceProcessor, HttpServletResponseEx responseEx) {
-    responseEx.setChunked(true);
+    responseEx.setChunkedForEvent(true);
     refreshEventId(invocation.getRequestEx(), produceProcessor);
     CompletableFuture<Void> result = new CompletableFuture<>();
     Publisher<?> publisher = response.getResult();

foundations/foundation-vertx/src/main/java/org/apache/servicecomb/foundation/vertx/http/HttpServletResponseEx.java

@@ -48,4 +48,8 @@ default Flowable<Buffer> getFlowableBuffer() {
   }
 
   void endResponse() throws IOException;
+
+  default void setChunkedForEvent(boolean chunked) {
+    // not set header transfer-encoding=chunked in Rest Over Servlet, or will have Multiple in response.
+  }
 }

foundations/foundation-vertx/src/main/java/org/apache/servicecomb/foundation/vertx/http/VertxServerResponseToHttpServletResponse.java

@@ -153,4 +153,9 @@ public CompletableFuture<Void> sendBuffer(Buffer buffer) {
     });
     return future;
   }
+
+  @Override
+  public void setChunkedForEvent(boolean chunked) {
+    serverResponse.setChunked(chunked);
+  }
 }