From 887d2ef677e66a0a1a6e6cca1faa6467ad252e96 Mon Sep 17 00:00:00 2001
From: Michael Lumish <mlumish@google.com>
Date: Tue, 2 Feb 2021 14:16:10 -0800
Subject: [PATCH] Kick the ResolvingLoadBalancer out of IDLE when the first
 call is started.

---
 packages/grpc-js/src/channel.ts | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/packages/grpc-js/src/channel.ts b/packages/grpc-js/src/channel.ts
index 7c61aa1f..fd015aff 100644
--- a/packages/grpc-js/src/channel.ts
+++ b/packages/grpc-js/src/channel.ts
@@ -261,6 +261,7 @@ export class ChannelImplementation implements Channel {
           for (const {callStream, callMetadata} of this.configSelectionQueue) {
             this.tryGetConfig(callStream, callMetadata);
           }
+          this.configSelectionQueue = [];
         });
       }
     );
@@ -474,6 +475,11 @@ export class ChannelImplementation implements Channel {
 
   private tryGetConfig(stream: Http2CallStream, metadata: Metadata) {
     if (this.configSelector === null) {
+      /* This branch will only be taken at the beginning of the channel's life,
+       * before the resolver ever returns a result. So, the
+       * ResolvingLoadBalancer may be idle and if so it needs to be kicked
+       * because it now has a pending request. */
+      this.resolvingLoadBalancer.exitIdle();
       this.callRefTimer.ref?.();
       this.configSelectionQueue.push({ 
         callStream: stream,