Send the client the command id as soon as possible

Previously the client was dependent on stdout/stderr or other interactions to
receive the command id, which is necessary to cancel the command. Send the
command id right away so we can cancel sooner.

--
MOS_MIGRATED_REVID=133282720

1 files changed, 13 insertions, 0 deletions

diff --git a/src/main/java/com/google/devtools/build/lib/server/GrpcServerImpl.java b/src/main/java/com/google/devtools/build/lib/server/GrpcServerImpl.java
index 1daa6e9d9c..13837415f0 100644
--- a/src/main/java/com/google/devtools/build/lib/server/GrpcServerImpl.java
+++ b/src/main/java/com/google/devtools/build/lib/server/GrpcServerImpl.java
@@ -625,6 +625,19 @@ public class GrpcServerImpl extends RPCServer {
 
     try (RunningCommand command = new RunningCommand()) {
       commandId = command.id;
+
+      try {
+        // Send the client the command id as soon as we know it.
+        observer.onNext(
+            RunResponse.newBuilder()
+                .setCookie(responseCookie)
+                .setCommandId(commandId)
+                .build());
+      } catch (StatusRuntimeException e) {
+        log.info(
+            "The client cancelled the command before receiving the command id: " + e.getMessage());
+      }
+
       OutErr rpcOutErr =
           OutErr.create(
               new RpcOutputStream(command.id, StreamType.STDOUT, sink),