/* Copyright NetFoundry Inc. Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at https://www.apache.org/licenses/LICENSE-2.0 Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License. */ package controller import ( "bytes" "compress/gzip" cryptoTls "crypto/tls" "crypto/x509" "encoding/json" "fmt" "math/big" "os" "sync" "sync/atomic" gosundheit "github.com/AppsFlyer/go-sundheit" "github.com/michaelquigley/pfxlog" "github.com/openziti/channel/v4" "github.com/openziti/channel/v4/protobufs" "github.com/openziti/foundation/v2/concurrenz" "github.com/openziti/foundation/v2/versions" "github.com/openziti/identity" "github.com/openziti/metrics" "github.com/openziti/storage/boltz" "github.com/openziti/transport/v2" "github.com/openziti/transport/v2/tls" "github.com/openziti/xweb/v3" "github.com/openziti/ziti/common/capabilities" "github.com/openziti/ziti/common/concurrency" fabricMetrics "github.com/openziti/ziti/common/metrics" "github.com/openziti/ziti/common/pb/ctrl_pb" "github.com/openziti/ziti/common/profiler" "github.com/openziti/ziti/controller/bindpoints" "github.com/openziti/ziti/controller/command" "github.com/openziti/ziti/controller/config" "github.com/openziti/ziti/controller/db" "github.com/openziti/ziti/controller/env" "github.com/openziti/ziti/controller/event" "github.com/openziti/ziti/controller/events" "github.com/openziti/ziti/controller/handler_ctrl" "github.com/openziti/ziti/controller/handler_peer_ctrl" "github.com/openziti/ziti/controller/network" "github.com/openziti/ziti/controller/raft" "github.com/openziti/ziti/controller/raft/mesh" "github.com/openziti/ziti/controller/webapis" "github.com/openziti/ziti/controller/xctrl" "github.com/openziti/ziti/controller/xmgmt" "github.com/openziti/ziti/controller/xt" "github.com/openziti/ziti/controller/xt_random" "github.com/openziti/ziti/controller/xt_smartrouting" "github.com/openziti/ziti/controller/xt_sticky" "github.com/openziti/ziti/controller/xt_weighted" "github.com/pkg/errors" "github.com/sirupsen/logrus" "github.com/teris-io/shortid" ) type Controller struct { config *config.Config env *env.AppEnv network *network.Network raftController *raft.Controller localDispatcher *command.LocalDispatcher ctrlConnectHandler *handler_ctrl.ConnectHandler xctrls []xctrl.Xctrl xmgmts concurrenz.CopyOnWriteSlice[xmgmt.Xmgmt] xwebFactoryRegistry xweb.Registry xweb xweb.Instance ctrlListener channel.UnderlayListener mgmtListener channel.UnderlayListener shutdownC chan struct{} isShutdown atomic.Bool agentBindHandlers []channel.BindHandler metricsRegistry metrics.Registry versionProvider versions.VersionProvider eventDispatcher *events.Dispatcher apiData map[string][]event.ApiAddress apiDataBytes []byte apiDataOnce sync.Once xwebInitialized concurrency.InitState healthChecker gosundheit.Health } func init() { xweb.BindPointListenerFactoryRegistry = append(xweb.BindPointListenerFactoryRegistry, &bindpoints.BindPointListenerFactory{}) } func (c *Controller) GetPeerSigners() []*x509.Certificate { if c.raftController == nil || c.raftController.Mesh == nil { return nil } var certs []*x509.Certificate for _, peer := range c.raftController.Mesh.GetPeers() { certs = append(certs, peer.SigningCerts...) } return certs } func (c *Controller) GetPeerAddresses() []string { if c.raftController == nil || c.raftController.Mesh == nil { return nil } var addresses []string for _, peer := range c.raftController.Mesh.GetPeers() { addresses = append(addresses, peer.Address) } return addresses } func (c *Controller) GetId() *identity.TokenId { return c.config.Id } func (c *Controller) GetConfig() *config.Config { return c.config } func (c *Controller) GetMetricsRegistry() metrics.Registry { return c.metricsRegistry } func (c *Controller) GetOptions() *config.NetworkConfig { return c.config.Network } func (c *Controller) GetCommandDispatcher() command.Dispatcher { if c.raftController == nil { if c.localDispatcher != nil { return c.localDispatcher } devVersion := versions.MustParseSemVer("0.0.0") version := versions.MustParseSemVer(c.GetVersionProvider().Version()) c.localDispatcher = &command.LocalDispatcher{ EncodeDecodeCommands: devVersion.Equals(version), Limiter: command.NewRateLimiter(c.config.CommandRateLimiter, c.metricsRegistry, c.shutdownC), } return c.localDispatcher } return c.raftController } func (c *Controller) IsRaftEnabled() bool { return c.raftController != nil } func (c *Controller) IsRaftLeader() bool { if c.raftController == nil { return false } return c.raftController.IsLeader() } func (c *Controller) GetRaftIndex() uint64 { return c.raftController.Raft.LastIndex() } func (c *Controller) GetRaftInfo() (string, string, string) { id := c.config.Id.Token addr := c.raftController.Mesh.Addr().String() version := c.GetVersionProvider().Version() return addr, id, version } func (c *Controller) GetDb() boltz.Db { return c.config.Db } func (c *Controller) GetVersionProvider() versions.VersionProvider { return c.versionProvider } func (c *Controller) GetCloseNotify() <-chan struct{} { return c.shutdownC } func (c *Controller) GetRaftConfig() *config.RaftConfig { return c.config.Raft } func (c *Controller) GetCommandRateLimiterConfig() command.RateLimiterConfig { return c.config.CommandRateLimiter } func (c *Controller) RenderJsonConfig() (string, error) { return c.config.ToJson() } func (c *Controller) GetEnv() *env.AppEnv { return c.env } func NewController(cfg *config.Config, versionProvider versions.VersionProvider) (*Controller, error) { metricRegistry := metrics.NewRegistry(cfg.Id.Token, nil) shutdownC := make(chan struct{}) tlsHandshakeRateLimiter := command.NewAdaptiveRateLimitTracker(cfg.TlsHandshakeRateLimiter, metricRegistry, shutdownC) tls.SetSharedListenerRateLimiter(tlsHandshakeRateLimiter) log := pfxlog.Logger() c := &Controller{ config: cfg, shutdownC: shutdownC, xwebFactoryRegistry: xweb.NewRegistryMap(), metricsRegistry: metricRegistry, versionProvider: versionProvider, eventDispatcher: events.NewDispatcher(shutdownC), xwebInitialized: concurrency.NewInitState(), } xwebInstanceOptions := xweb.InstanceOptions{ DefaultIdentity: c.config.Id, DefaultIdentitySection: xweb.DefaultIdentitySection, DefaultConfigSection: xweb.DefaultConfigSection, ServerMutators: []xweb.ServerMutator{ func(instance xweb.Instance, serverConfig *xweb.ServerConfig, server *xweb.Server) error { for _, httpServer := range server.HttpServers { serverTlsConfig := httpServer.TLSConfig.Clone() prev := serverTlsConfig.GetConfigForClient httpServer.TLSConfig.GetConfigForClient = func(info *cryptoTls.ClientHelloInfo) (*cryptoTls.Config, error) { result := serverTlsConfig //use inner GetConfigForClient if it was defined if prev != nil { var err error result, err = prev(info) if err != nil { return nil, err } } result.ClientCAs = c.env.GetManagers().Ca.GetTrustCache().GetAllPool() return result, nil } } return nil }, }, } c.xweb = xweb.NewInstance(c.xwebFactoryRegistry, xwebInstanceOptions) if cfg.IsRaftEnabled() { c.raftController = raft.NewController(c, c) if err := c.raftController.Init(); err != nil { log.WithError(err).Panic("error starting raft") } cfg.Db = c.raftController.GetDb() } c.registerXts() appEnv, err := env.NewAppEnv(c) if err != nil { return nil, err } c.env = appEnv if n, err := network.NewNetwork(c, appEnv); err == nil { c.network = n } else { return nil, err } if c.raftController != nil { if err = c.raftController.InitEnv(c.env); err != nil { return nil, err } } c.initWeb() // need to init web before bootstrapping, so we can provide our endpoints to peers if c.raftController != nil && !c.raftController.IsBootstrapped() { if err = c.TryInitializeRaftFromBoltDb(); err != nil { log.WithError(err).Panic("error bootstrapping raft") } } c.eventDispatcher.InitializeNetworkEvents(c.network) if cfg.Ctrl.Options.NewListener != nil { c.network.AddRouterPresenceHandler(&OnConnectSettingsHandler{ config: cfg, settings: map[int32][]byte{ int32(ctrl_pb.SettingTypes_NewCtrlAddress): []byte((*cfg.Ctrl.Options.NewListener).String()), }, }) } if c.raftController != nil { logrus.Info("Adding router presence handler to send out ctrl addresses") c.network.AddRouterPresenceHandler( NewOnConnectCtrlAddressesUpdateHandler(c.config.Ctrl.Listener.String(), c.raftController), ) } if err := c.showOptions(); err != nil { return nil, err } return c, nil } func (c *Controller) initWeb() { healthChecker, err := c.initializeHealthChecks() if err != nil { logrus.WithError(err).Fatalf("failed to create health checker") } c.healthChecker = healthChecker if err = c.xweb.GetRegistry().Add(webapis.NewControllerHealthCheckApiFactory(c.env, healthChecker)); err != nil { logrus.WithError(err).Fatalf("failed to create health checks api factory") } fabricManagementFactory := webapis.NewFabricManagementApiFactory(c.config.Id, c.env, c.network, &c.xmgmts) if err = c.xweb.GetRegistry().Add(fabricManagementFactory); err != nil { logrus.WithError(err).Fatalf("failed to create management api factory") } if err = c.xweb.GetRegistry().Add(webapis.NewMetricsApiFactory(c.config.Id, c.network)); err != nil { logrus.WithError(err).Fatalf("failed to create metrics api factory") } if err = c.xweb.GetRegistry().Add(webapis.NewZitiAdminConsoleFactory()); err != nil { logrus.WithError(err).Fatalf("failed to create single page application factory") } if c.IsEdgeEnabled() { managementApiFactory := webapis.NewManagementApiFactory(c.env) clientApiFactory := webapis.NewClientApiFactory(c.env) oidcApiFactory := webapis.NewOidcApiFactory(c.env) if err = c.xweb.GetRegistry().Add(managementApiFactory); err != nil { pfxlog.Logger().Fatalf("failed to create Edge Management API factory: %v", err) } if err = c.xweb.GetRegistry().Add(clientApiFactory); err != nil { pfxlog.Logger().Fatalf("failed to create Edge Client API factory: %v", err) } if err = c.xweb.GetRegistry().Add(oidcApiFactory); err != nil { pfxlog.Logger().Fatalf("failed to create OIDC API factory: %v", err) } webapis.OverrideRequestWrapper(webapis.NewFabricApiWrapper(c.env)) } else { // if no edge we need 1 default API, make the fabric api the default fabricManagementFactory.MakeDefault = true } c.xwebInitialized.MarkInitialized() } func (c *Controller) IsEdgeEnabled() bool { return c.config.Edge.Enabled } func (c *Controller) Run() error { c.startProfiling() if err := c.registerComponents(); err != nil { return fmt.Errorf("error registering component: %s", err) } versionInfo := c.network.VersionProvider.AsVersionInfo() versionHeader, err := c.network.VersionProvider.EncoderDecoder().Encode(versionInfo) if err != nil { pfxlog.Logger().Panicf("could not prepare version headers: %v", err) } capabilityMask := &big.Int{} capabilityMask.SetBit(capabilityMask, capabilities.ControllerCreateTerminatorV2, 1) capabilityMask.SetBit(capabilityMask, capabilities.ControllerSingleRouterLinkSource, 1) capabilityMask.SetBit(capabilityMask, capabilities.ControllerCreateCircuitV2, 1) if c.config.RouterDataModel.Enabled || c.raftController != nil { capabilityMask.SetBit(capabilityMask, capabilities.RouterDataModel, 1) } headers := map[int32][]byte{ channel.HelloVersionHeader: versionHeader, int32(ctrl_pb.ControlHeaders_CapabilitiesHeader): capabilityMask.Bytes(), } /** * ctrl listener/accepter. */ ctrlChannelListenerConfig := channel.ListenerConfig{ ConnectOptions: c.config.Ctrl.Options.ConnectOptions, PoolConfigurator: fabricMetrics.GoroutinesPoolMetricsConfigF(c.network.GetMetricsRegistry(), "pool.listener.ctrl"), Headers: headers, TransportConfig: transport.Configuration{"protocol": "ziti-ctrl"}, } if c.raftController != nil { ctrlChannelListenerConfig.HeadersF = c.raftController.GetListenerHeaders } ctrlListener := channel.NewClassicListener(c.config.Id, c.config.Ctrl.Listener, ctrlChannelListenerConfig) c.ctrlListener = ctrlListener if err := c.ctrlListener.Listen(c.ctrlConnectHandler); err != nil { panic(err) } ctrlAccepter := handler_ctrl.NewCtrlAccepter(c.network, c.xctrls, c.config.Ctrl.Options.Options, c.config.Ctrl.Options.RouterHeartbeatOptions, c.config.Trace.Handler) ctrlAcceptors := map[string]channel.UnderlayAcceptor{} if c.raftController != nil { c.raftController.ConfigureMeshHandlers(handler_peer_ctrl.NewBindHandler(c.network, c.raftController, c.config.Ctrl.Options.PeerHeartbeatOptions)) ctrlAcceptors[mesh.ChannelTypeMesh] = c.raftController.GetMesh() } underlayDispatcher := channel.NewUnderlayDispatcher(channel.UnderlayDispatcherConfig{ Listener: ctrlListener, ConnectTimeout: c.config.Ctrl.Options.ConnectTimeout, Acceptors: ctrlAcceptors, DefaultAcceptor: ctrlAccepter, }) go underlayDispatcher.Run() if err = c.config.Configure(c.xweb); err != nil { panic(err) } c.xweb.Run() for _, helloHeader := range c.GetHelloHeaderProviders() { helloHeader.Apply(headers) } // event handlers if err := c.eventDispatcher.WireEventHandlers(c.getEventHandlerConfigs()); err != nil { panic(err) } if c.raftController != nil { c.raftController.StartEventGeneration() } c.network.Run() return nil } func (c *Controller) getEventHandlerConfigs() []*events.EventHandlerConfig { var result []*events.EventHandlerConfig if e, ok := c.config.Src["events"]; ok { if em, ok := e.(map[interface{}]interface{}); ok { for id, v := range em { if config, ok := v.(map[interface{}]interface{}); ok { result = append(result, &events.EventHandlerConfig{ Id: id, Config: config, }) } } } } return result } func (c *Controller) GetCloseNotifyChannel() <-chan struct{} { return c.shutdownC } func (c *Controller) Shutdown() { if c.isShutdown.CompareAndSwap(false, true) { close(c.shutdownC) if c.ctrlListener != nil { if err := c.ctrlListener.Close(); err != nil { pfxlog.Logger().WithError(err).Error("failed to close ctrl channel listener") } } if c.mgmtListener != nil { if err := c.mgmtListener.Close(); err != nil { pfxlog.Logger().WithError(err).Error("failed to close mgmt channel listener") } } if c.config.Db != nil { if err := c.config.Db.Close(); err != nil { pfxlog.Logger().WithError(err).Error("failed to close db") } } go c.xweb.Shutdown() if c.raftController != nil { if err := c.raftController.Shutdown(); err != nil { pfxlog.Logger().WithError(err).Error("failed to shutdown raft") } } c.config.Id.StopWatchingFiles() if c.config.Edge.Enrollment.SigningCert != nil { c.config.Edge.Enrollment.SigningCert.StopWatchingFiles() } if c.healthChecker != nil { c.healthChecker.DeregisterAll() } } } func (c *Controller) showOptions() error { if ctrl, err := json.MarshalIndent(c.config.Ctrl.Options, "", " "); err == nil { pfxlog.Logger().Infof("ctrl = %s", string(ctrl)) } else { return err } return nil } func (c *Controller) startProfiling() { if c.config.Profile.Memory.Path != "" { go profiler.NewMemoryWithShutdown(c.config.Profile.Memory.Path, c.config.Profile.Memory.Interval, c.shutdownC).Run() } if c.config.Profile.CPU.Path != "" { if cpu, err := profiler.NewCPUWithShutdown(c.config.Profile.CPU.Path, c.shutdownC); err == nil { go cpu.Run() } else { logrus.Errorf("unexpected error launching cpu profiling (%v)", err) } } } func (c *Controller) registerXts() { xt.GlobalRegistry().RegisterFactory(xt_smartrouting.NewFactory()) xt.GlobalRegistry().RegisterFactory(xt_random.NewFactory()) xt.GlobalRegistry().RegisterFactory(xt_weighted.NewFactory()) xt.GlobalRegistry().RegisterFactory(xt_sticky.NewFactory()) } func (c *Controller) registerComponents() error { c.ctrlConnectHandler = handler_ctrl.NewConnectHandler(c.config.Id, c.network) c.eventDispatcher.AddClusterEventHandler(event.ClusterEventHandlerF(c.routerDispatchCallback)) return nil } func (c *Controller) RegisterXctrl(x xctrl.Xctrl) error { if err := c.config.Configure(x); err != nil { return err } if x.Enabled() { c.xctrls = append(c.xctrls, x) if c.config.Trace.Handler != nil { for _, decoder := range x.GetTraceDecoders() { c.config.Trace.Handler.AddDecoder(decoder) } } } return nil } func (c *Controller) RegisterXmgmt(x xmgmt.Xmgmt) error { if err := c.config.Configure(x); err != nil { return err } pfxlog.Logger().Infof("adding xmgmt %T, enabled? %v", x, x.Enabled()) if x.Enabled() { c.xmgmts.Append(x) } return nil } func (c *Controller) GetXWebInstance() xweb.Instance { return c.xweb } func (c *Controller) GetNetwork() *network.Network { return c.network } func (c *Controller) Identity() identity.Identity { return c.config.Id } func (c *Controller) GetEventDispatcher() event.Dispatcher { return c.eventDispatcher } func (c *Controller) routerDispatchCallback(evt *event.ClusterEvent) { if evt.EventType == event.ClusterLeadershipGained { req := &ctrl_pb.UpdateClusterLeader{ Index: evt.Index, } for _, r := range c.network.AllConnectedRouters() { log := pfxlog.Logger().WithFields(map[string]interface{}{ "index": evt.Index, }) if err := protobufs.MarshalTyped(req).Send(r.Control); err != nil { pfxlog.Logger().WithError(err).WithField("routerId", r.Id).Error("unable to update cluster leader on router") } else { log.WithField("routerId", r.Id).WithField("routerName", r.Name).Info("router updated with info on new leader") } } } if evt.EventType == event.ClusterMembersChanged { var endpoints []string for _, peer := range evt.Peers { endpoints = append(endpoints, peer.Addr) } updMsg := &ctrl_pb.UpdateCtrlAddresses{ Addresses: endpoints, IsLeader: c.raftController.IsLeader(), Index: evt.Index, } log := pfxlog.Logger().WithFields(map[string]interface{}{ "addresses": endpoints, "index": evt.Index, }) log.Info("syncing updated ctrl addresses to connected routers") for _, r := range c.network.AllConnectedRouters() { if err := protobufs.MarshalTyped(updMsg).Send(r.Control); err != nil { pfxlog.Logger().WithError(err).WithField("routerId", r.Id).Error("unable to update controller endpoints on router") } else { log.WithField("routerId", r.Id).WithField("routerName", r.Name).Info("router updated with latest ctrl addresses") } } } } func (c *Controller) getMigrationDb() (*string, error) { val, found := c.config.Src["db"] if !found { return nil, nil } path := fmt.Sprintf("%v", val) if _, err := os.Stat(path); err != nil { if os.IsNotExist(err) { return nil, errors.Wrapf(err, "source db not found at [%v], either remove 'db' config setting or fix path ", path) } return nil, errors.Wrapf(err, "invalid db path [%v]", path) } return &path, nil } func (c *Controller) ValidateMigrationEnvironment() error { _, err := c.getMigrationDb() return err } func (c *Controller) TryInitializeRaftFromBoltDb() error { path, err := c.getMigrationDb() if err != nil || path == nil { return err } return c.InitializeRaftFromBoltDb(*path) } func (c *Controller) InitializeRaftFromBoltDb(sourceDbPath string) error { log := pfxlog.Logger() if c.raftController == nil { return errors.New("can't initialize non-raft controller using initialize from db") } if c.raftController.IsBootstrapped() { return errors.New("raft is already bootstrapped, must start with a uninitialized controller") } if _, err := os.Stat(sourceDbPath); err != nil { if os.IsNotExist(err) { return errors.Wrapf(err, "source db not found at [%v]", sourceDbPath) } return errors.Wrapf(err, "invalid db path [%v]", sourceDbPath) } sourceDb, err := db.Open(sourceDbPath) if err != nil { return err } defer func() { if err = sourceDb.Close(); err != nil { log.WithError(err).Error("error closing migration source bolt db") } }() timelineId, err := sourceDb.GetTimelineId(boltz.TimelineModeForceReset, shortid.Generate) if err != nil { return err } log.WithField("timelineId", timelineId).WithField("path", sourceDbPath).Info("initializing from bolt db") buf := &bytes.Buffer{} gzWriter := gzip.NewWriter(buf) if err = sourceDb.StreamToWriter(gzWriter); err != nil { return err } if err = gzWriter.Close(); err != nil { return errors.Wrap(err, "error finishing gz compression of migration snapshot") } // need to override in case there's an existing db in a restore scenario. See: https://github.com/openziti/ziti/issues/2891 c.env.OverrideTimelineId(timelineId) cmd := &command.SyncSnapshotCommand{ TimelineId: timelineId, Snapshot: buf.Bytes(), SnapshotSink: c.network.RestoreSnapshot, } if err = c.raftController.Bootstrap(); err != nil { return fmt.Errorf("unable to bootstrap cluster (%w)", err) } return c.raftController.Dispatch(cmd) } func (c *Controller) RaftRestoreFromBoltDb(sourceDbPath string) error { log := pfxlog.Logger() if c.raftController == nil { return errors.New("can't initialize non-raft controller using initialize from db") } if _, err := os.Stat(sourceDbPath); err != nil { if os.IsNotExist(err) { return errors.Wrapf(err, "source db not found at [%v]", sourceDbPath) } return errors.Wrapf(err, "invalid db path [%v]", sourceDbPath) } sourceDb, err := db.Open(sourceDbPath) if err != nil { return err } defer func() { if err = sourceDb.Close(); err != nil { log.WithError(err).Error("error closing migration source bolt db") } }() timelineId, err := sourceDb.GetTimelineId(boltz.TimelineModeForceReset, shortid.Generate) if err != nil { return err } log.WithField("timelineId", timelineId).WithField("path", sourceDbPath).Info("restoring from bolt db") buf := &bytes.Buffer{} gzWriter := gzip.NewWriter(buf) if err = sourceDb.StreamToWriter(gzWriter); err != nil { return err } if err = gzWriter.Close(); err != nil { return errors.Wrap(err, "error finishing gz compression of migration snapshot") } cmd := &command.SyncSnapshotCommand{ TimelineId: timelineId, Snapshot: buf.Bytes(), SnapshotSink: c.network.RestoreSnapshot, } if err = c.raftController.Bootstrap(); err != nil { return fmt.Errorf("unable to bootstrap cluster (%w)", err) } return c.raftController.Dispatch(cmd) } // TODO: this functions is a temporary hack and should be provided by xweb func getApiPath(binding string) string { switch binding { case "edge-client": return "/edge/client/v1" case "edge-management": return "/edge/management/v1" case "fabric": return "/fabric/v1" case "health-checks": return "/health-checks" case "edge-oidc": return "/oidc" } return "" } func (c *Controller) GetApiAddresses() (map[string][]event.ApiAddress, []byte) { c.apiDataOnce.Do(func() { c.xwebInitialized.WaitTillInitialized() xwebConfig := c.xweb.GetConfig() apiData := map[string][]event.ApiAddress{} for _, serverConfig := range xwebConfig.ServerConfigs { for _, bindPoint := range serverConfig.BindPoints { for _, api := range serverConfig.APIs { apiData[api.Binding()] = append(apiData[api.Binding()], event.ApiAddress{ Url: "https://" + bindPoint.ServerAddress() + getApiPath(api.Binding()), //TODO: temp till xweb support reporting API paths Version: "v1", //TODO: temp till xweb supports reporting versions via api.Version() }) } } } c.apiData = apiData c.apiDataBytes, _ = json.Marshal(apiData) }) return c.apiData, c.apiDataBytes } func (c *Controller) GetHelloHeaderProviders() []mesh.HeaderProvider { providerFunc := func(headers map[int32][]byte) { _, apiDataBytes := c.GetApiAddresses() headers[mesh.ApiAddressesHeader] = apiDataBytes } provider := mesh.HeaderProviderFunc(providerFunc) return []mesh.HeaderProvider{provider} }