Add config for controlling node ip resolution

Author: mini-ninja-64

proxy/pkg/config/config.go

@@ -47,6 +47,8 @@ type Config struct {
 	OriginTlsClientCertPath string `split_words:"true" yaml:"origin_tls_client_cert_path"`
 	OriginTlsClientKeyPath  string `split_words:"true" yaml:"origin_tls_client_key_path"`
 
+	OriginPreferIpFromSystemLocal bool `default:"true" split_words:"true" yaml:"origin_prefer_ip_from_system_local"`
+
 	// Target bucket
 
 	TargetContactPoints           string `split_words:"true" yaml:"target_contact_points"`
@@ -61,6 +63,8 @@ type Config struct {
 	TargetTlsClientCertPath string `split_words:"true" yaml:"target_tls_client_cert_path"`
 	TargetTlsClientKeyPath  string `split_words:"true" yaml:"target_tls_client_key_path"`
 
+	TargetPreferIpFromSystemLocal bool `default:"true" split_words:"true" yaml:"target_prefer_ip_from_system_local"`
+
 	// Proxy bucket
 
 	ProxyListenAddress        string `default:"localhost" split_words:"true" yaml:"proxy_listen_address"`

proxy/pkg/zdmproxy/controlconn.go

@@ -55,6 +55,7 @@ type ControlConn struct {
 	protocolEventSubscribers map[ProtocolEventObserver]interface{}
 	authEnabled              *atomic.Value
 	metricsHandler           *metrics.MetricHandler
+	preferIpFromSystemLocal  bool
 }
 
 const ProxyVirtualRack = "rack0"
@@ -64,7 +65,7 @@ const ccReadTimeout = 10 * time.Second
 
 func NewControlConn(ctx context.Context, defaultPort int, connConfig ConnectionConfig,
 	username string, password string, conf *config.Config, topologyConfig *common.TopologyConfig, proxyRand *rand.Rand,
-	metricsHandler *metrics.MetricHandler) *ControlConn {
+	metricsHandler *metrics.MetricHandler, preferIpFromSystemLocal bool) *ControlConn {
 	authEnabled := &atomic.Value{}
 	authEnabled.Store(true)
 	return &ControlConn{
@@ -102,6 +103,7 @@ func NewControlConn(ctx context.Context, defaultPort int, connConfig ConnectionC
 		protocolEventSubscribers: map[ProtocolEventObserver]interface{}{},
 		authEnabled:              authEnabled,
 		metricsHandler:           metricsHandler,
+		preferIpFromSystemLocal:  preferIpFromSystemLocal,
 	}
 }
 
@@ -445,6 +447,7 @@ func (cc *ControlConn) RefreshHosts(conn CqlConnection, ctx context.Context) ([]
 	if partitionerExists {
 		partitioner = partitionerColValue.AsNillableString()
 	}
+
 	if partitioner != nil && !strings.Contains(*partitioner, "Murmur3Partitioner") && cc.topologyConfig.VirtualizationEnabled {
 		if strings.Contains(*partitioner, "RandomPartitioner") {
 			log.Debugf("Cluster %v uses the Random partitioner, but the proxy will return Murmur3 to the client instead. This is the expected behaviour.", cc.connConfig.GetClusterType())
@@ -475,11 +478,19 @@ func (cc *ControlConn) RefreshHosts(conn CqlConnection, ctx context.Context) ([]
 		}
 	}
 
-	oldLocalhost, localHostExists := hostsById[localHost.HostId]
-	if localHostExists {
-		log.Warnf("Local host is also on the peers list: %v vs %v, ignoring the former one.", oldLocalhost, localHost)
+	peersListLocalHost, peersListContainsLocalHost := hostsById[localHost.HostId]
+	if cc.preferIpFromSystemLocal {
+		if peersListContainsLocalHost {
+			log.Warnf("Local host is also on the peers list: %v vs %v, ignoring the former one.", peersListLocalHost, localHost)
+		}
+		hostsById[localHost.HostId] = localHost
+	} else if peersListContainsLocalHost {
+		log.Infof("Local host is on the peers list aswell, the peers list will be used as the source of truth: %v vs %v, ignoring the latter one.", peersListLocalHost, localHost)
+	} else {
+		log.Warnf("Local host is not on the peers list, it will be added: %v.", localHost)
+		hostsById[localHost.HostId] = localHost
 	}
-	hostsById[localHost.HostId] = localHost
+
 	orderedLocalHosts := make([]*Host, 0, len(hostsById))
 	for _, h := range hostsById {
 		orderedLocalHosts = append(orderedLocalHosts, h)

proxy/pkg/zdmproxy/proxy.go

@@ -249,7 +249,7 @@ func (p *ZdmProxy) initializeControlConnections(ctx context.Context) error {
 
 	originControlConn := NewControlConn(
 		p.controlConnShutdownCtx, p.Conf.OriginPort, p.originConnectionConfig,
-		p.Conf.OriginUsername, p.Conf.OriginPassword, p.Conf, topologyConfig, p.proxyRand, p.metricHandler)
+		p.Conf.OriginUsername, p.Conf.OriginPassword, p.Conf, topologyConfig, p.proxyRand, p.metricHandler, p.Conf.OriginPreferIpFromSystemLocal)
 
 	if err := originControlConn.Start(p.controlConnShutdownWg, ctx); err != nil {
 		return fmt.Errorf("failed to initialize origin control connection: %w", err)
@@ -261,7 +261,7 @@ func (p *ZdmProxy) initializeControlConnections(ctx context.Context) error {
 
 	targetControlConn := NewControlConn(
 		p.controlConnShutdownCtx, p.Conf.TargetPort, p.targetConnectionConfig,
-		p.Conf.TargetUsername, p.Conf.TargetPassword, p.Conf, topologyConfig, p.proxyRand, p.metricHandler)
+		p.Conf.TargetUsername, p.Conf.TargetPassword, p.Conf, topologyConfig, p.proxyRand, p.metricHandler, p.Conf.TargetPreferIpFromSystemLocal)
 
 	if err := targetControlConn.Start(p.controlConnShutdownWg, ctx); err != nil {
 		return fmt.Errorf("failed to initialize target control connection: %w", err)