redis: skip resolution for ip address

source/extensions/clusters/redis/redis_cluster.cc

@@ -160,6 +160,19 @@ RedisCluster::DnsDiscoveryResolveTarget::~DnsDiscoveryResolveTarget() {
 void RedisCluster::DnsDiscoveryResolveTarget::startResolveDns() {
   ENVOY_LOG(trace, "starting async DNS resolution for {}", dns_address_);
 
+  Network::Address::InstanceConstSharedPtr(ip_address);
+  try {
+    ip_address = Network::Utility::parseInternetAddress(dns_address_, port_, false);
+  } catch (const EnvoyException& e) {
+  }
+
+  if (ip_address != nullptr) {
+    ENVOY_LOG(trace, "start resolve redis without dns for {}", ip_address);
+    parent_.redis_discovery_session_.registerAddress(ip_address);
+    parent_.redis_discovery_session_.startResolveRedis();
+    return;
+  }
+
   active_query_ = parent_.dns_resolver_->resolve(
       dns_address_, parent_.dns_lookup_family_,
       [this](Network::DnsResolver::ResolutionStatus status,
@@ -262,6 +275,11 @@ void RedisCluster::RedisDiscoverySession::registerDiscoveryAddress(
   }
 }
 
+void RedisCluster::RedisDiscoverySession::registerAddress(
+    Network::Address::InstanceConstSharedPtr address) {
+  discovery_address_list_.push_back(address);
+}
+
 void RedisCluster::RedisDiscoverySession::startResolveRedis() {
   parent_.info_->stats().update_attempt_.inc();
   // If a resolution is currently in progress, skip it.

source/extensions/clusters/redis/redis_cluster.h

@@ -206,6 +206,7 @@ class RedisCluster : public Upstream::BaseDynamicClusterImpl {
     ~RedisDiscoverySession() override;
 
     void registerDiscoveryAddress(std::list<Network::DnsResponse>&& response, const uint32_t port);
+    void registerAddress(Network::Address::InstanceConstSharedPtr address);
 
     // Start discovery against a random host from existing hosts
     void startResolveRedis();