fix: reapply RST_STREAM(cancel) workaround, and disable grpc-timeout (d…

…eephaven#6478)

Changes from deephaven#6420 were supposed to be reverted in deephaven#6424, but apparently
git interpreted the branch's relationship with main differently than I
did.

This patch reapplies deephaven#6401, with an additional change to avoid noisy
stack traces from grpc clients that set `grpc-timeout`. At this time,
Deephaven doesn't handle timeouts nor do any default clients set
timeouts, so the impact here should be minimal.

Fixes deephaven#5996 
See deephaven#6400

grpc-java/grpc-servlet-jakarta/src/main/java/io/grpc/servlet/jakarta/AsyncServletOutputStreamWriter.java

@@ -121,9 +121,15 @@ public boolean isFinestEnabled() {
             transportState.runOnTransportThread(
                     () -> {
                         transportState.complete();
-                        asyncContext.complete();
+                        // asyncContext.complete();
                         log.fine("call completed");
                     });
+            // Jetty specific fix: When AsyncContext.complete() is called, Jetty sends a RST_STREAM with
+            // "cancel" error to the client, while other containers send "no error" in this case. Calling
+            // close() instead on the output stream still sends the RST_STREAM, but with "no error". Note
+            // that this does the opposite in at least Tomcat, so we're not going to upstream this change.
+            // See https://github.com/deephaven/deephaven-core/issues/6400
+            outputStream.close();
         };
         this.isReady = () -> outputStream.isReady();
     }

grpc-java/grpc-servlet-jakarta/src/main/java/io/grpc/servlet/jakarta/ServletAdapter.java

@@ -143,7 +143,10 @@ public void doPost(HttpServletRequest req, HttpServletResponse resp) throws IOEx
             logger.log(FINEST, "[{0}] headers: {1}", new Object[] {logId, headers});
         }
 
-        Long timeoutNanos = headers.get(TIMEOUT_KEY);
+        // Always ignore grpc-timeout at this time, as the servlet timeout isn't being reset
+        // when the output stream is closed. See https://github.com/deephaven/deephaven-core/issues/6400
+        // for more information.
+        Long timeoutNanos = null; // headers.get(TIMEOUT_KEY);
         if (timeoutNanos == null) {
             timeoutNanos = 0L;
         }