From ee300dbdbe918acfa59e478c04adb6f4587b905d Mon Sep 17 00:00:00 2001
From: Vivek Singh Chauhan <vchauhan@axway.com>
Date: Thu, 14 Nov 2024 13:41:10 -0700
Subject: [PATCH] APIGOV-29235 - override resolver for gRPC (#858)

* INT - override resolver for gRPC

* INT - moved resolver builder to utils for reusability
---
 pkg/util/dialer.go          | 40 +++++++++++++++++++++++++++++++++++++
 pkg/watchmanager/manager.go |  5 +++++
 2 files changed, 45 insertions(+)

diff --git a/pkg/util/dialer.go b/pkg/util/dialer.go
index 14331e65f..d0a0345e4 100644
--- a/pkg/util/dialer.go
+++ b/pkg/util/dialer.go
@@ -12,6 +12,7 @@ import (
 
 	"github.com/Axway/agent-sdk/pkg/util/log"
 	"golang.org/x/net/proxy"
+	gr "google.golang.org/grpc/resolver"
 )
 
 const (
@@ -167,3 +168,42 @@ func (d *dialer) createConnectRequest(ctx context.Context, targetAddress, sniHos
 	}
 	return req.WithContext(ctx)
 }
+
+type customGRPCResolverBuilder struct {
+	addr      string
+	authority string
+	schema    string
+}
+
+func CreateCustomGRPCResolverBuilder(addr, authority, scheme string) gr.Builder {
+	return &customGRPCResolverBuilder{
+		addr:      addr,
+		authority: authority,
+		schema:    scheme,
+	}
+}
+
+func (b *customGRPCResolverBuilder) Build(target gr.Target, cc gr.ClientConn, _ gr.BuildOptions) (gr.Resolver, error) {
+	cc.UpdateState(gr.State{Endpoints: []gr.Endpoint{
+		{
+			Addresses: []gr.Address{
+				{
+					Addr:       b.addr,
+					ServerName: b.authority,
+				},
+			},
+		},
+	}})
+	return &nopResolver{}, nil
+}
+
+func (b *customGRPCResolverBuilder) Scheme() string {
+	return b.schema
+}
+
+type nopResolver struct {
+}
+
+func (*nopResolver) ResolveNow(gr.ResolveNowOptions) {}
+
+func (*nopResolver) Close() {}
diff --git a/pkg/watchmanager/manager.go b/pkg/watchmanager/manager.go
index cd741555f..99941097a 100644
--- a/pkg/watchmanager/manager.go
+++ b/pkg/watchmanager/manager.go
@@ -87,6 +87,11 @@ func (m *watchManager) createConnection() (*grpc.ClientConn, error) {
 			logrusStreamClientInterceptor(m.options.loggerEntry),
 		),
 		grpc.WithUserAgent(m.cfg.UserAgent),
+		grpc.WithResolvers(
+			util.CreateCustomGRPCResolverBuilder(
+				fmt.Sprintf("%s:%d", m.cfg.Host, m.cfg.Port),
+				m.cfg.Host,
+				"https")),
 	}
 
 	m.logger.