Fix channel config callback in gateway

Currently, the config update callback triggers a discovery call to get the updated channel orderers.
However, this relies on the discovery service having processed the config message before the gateway.  If it hasn’t, the gateway just gets the stale orderer config.
This commit changes the logic so the gateway extracts the orderer endpoints directly from the config bundle.

Signed-off-by: andrew-coleman <andrew_coleman@uk.ibm.com>
(cherry picked from commit 8576508)

core/peer/peer.go

@@ -315,14 +315,14 @@ func (p *Peer) createChannel(
 		cryptoProvider: p.CryptoProvider,
 	}
 
-	callbacks := append(
-		p.configCallbacks,
+	callbacks := []channelconfig.BundleActor{
 		ordererSourceCallback,
 		gossipCallbackWrapper,
 		trustedRootsCallbackWrapper,
 		mspCallback,
 		channel.bundleUpdate,
-	)
+	}
+	callbacks = append(callbacks, p.configCallbacks...)
 
 	channel.bundleSource = channelconfig.NewBundleSource(
 		bundle,

internal/pkg/gateway/registry.go

@@ -400,27 +400,34 @@ func (reg *registry) config(channel string) ([]*endpointConfig, error) {
 	}
 	var channelOrderers []*endpointConfig
 	for mspid, eps := range config.GetOrderers() {
+		var tlsRootCerts [][]byte
+		if mspInfo, ok := config.GetMsps()[mspid]; ok {
+			tlsRootCerts = mspInfo.GetTlsRootCerts()
+		}
 		for _, ep := range eps.Endpoint {
 			address := fmt.Sprintf("%s:%d", ep.Host, ep.Port)
-			var tlsRootCerts [][]byte
-			if mspInfo, ok := config.GetMsps()[mspid]; ok {
-				tlsRootCerts = mspInfo.GetTlsRootCerts()
-			}
 			channelOrderers = append(channelOrderers, &endpointConfig{address: address, mspid: mspid, tlsRootCerts: tlsRootCerts})
 		}
 	}
 	return channelOrderers, nil
 }
 
 func (reg *registry) configUpdate(bundle *channelconfig.Bundle) {
-	if _, ok := bundle.OrdererConfig(); ok {
-		// orderer config has changed - invalidate the cache for this channel
+	if ordererConfig, ok := bundle.OrdererConfig(); ok {
+		// orderer config has changed - process the bundle
 		channel := bundle.ConfigtxValidator().ChannelID()
-		channelOrderers, err := reg.config(channel)
-		if err != nil {
-			reg.logger.Errorw("Failed update orderer config", "channel", channel, "err", err)
-			return
+		reg.logger.Infow("Updating orderer config", "channel", channel)
+		var channelOrderers []*endpointConfig
+		for _, org := range ordererConfig.Organizations() {
+			mspid := org.MSPID()
+			tlsRootCerts := org.MSP().GetTLSRootCerts()
+			for _, address := range org.Endpoints() {
+				channelOrderers = append(channelOrderers, &endpointConfig{address: address, mspid: mspid, tlsRootCerts: tlsRootCerts})
+				reg.logger.Debugw("Channel orderer", "address", address, "mspid", mspid)
+			}
+		}
+		if len(channelOrderers) > 0 {
+			reg.channelOrderers.Store(channel, channelOrderers)
 		}
-		reg.channelOrderers.Store(channel, channelOrderers)
 	}
 }

internal/pkg/gateway/registry_test.go

@@ -33,14 +33,7 @@ func TestOrdererCache(t *testing.T) {
 	require.NoError(t, err)
 	require.Len(t, orderers, 1)
 
-	// add 2 more orderer nodes
-	test.discovery.ConfigReturns(buildConfig(t, []string{"orderer1", "orderer2", "orderer3"}), nil)
-	// the config is cached in the registry - so will still return the single orderer
-	orderers, err = test.server.registry.orderers(channelName)
-	require.NoError(t, err)
-	require.Len(t, orderers, 1)
-
-	// the config update callback is triggered, which will invalidate the cache
+	// trigger the config update callback, updating the orderers
 	bundle, err := createChannelConfigBundle()
 	require.NoError(t, err)
 	test.server.registry.configUpdate(bundle)
@@ -74,6 +67,7 @@ func buildConfig(t *testing.T, orderers []string) *dp.ConfigResult {
 func createChannelConfigBundle() (*channelconfig.Bundle, error) {
 	conf := genesisconfig.Load(genesisconfig.SampleDevModeSoloProfile, configtest.GetDevConfigDir())
 	conf.Capabilities = map[string]bool{"V2_0": true}
+	conf.Orderer.Organizations[0].OrdererEndpoints = []string{"orderer1", "orderer2", "orderer3"}
 
 	cg, err := encoder.NewChannelGroup(conf)
 	if err != nil {