diff --git a/internal/config/config.go b/internal/config/config.go
index 089c7b83c6..644e9c8959 100644
--- a/internal/config/config.go
+++ b/internal/config/config.go
@@ -1,4 +1,4 @@
-// Copyright © 2021 Kaleido, Inc.
+// Copyright © 2022 Kaleido, Inc.
 //
 // SPDX-License-Identifier: Apache-2.0
 //
@@ -273,6 +273,9 @@ type PrefixArray interface {
 type RootKey string
 
 func Reset() {
+	keysMutex.Lock() // must only call viper directly here (as we already hold the lock)
+	defer keysMutex.Unlock()
+
 	viper.Reset()
 
 	// Set defaults
@@ -351,11 +354,14 @@ func Reset() {
 	viper.SetDefault(string(IdentityManagerCacheLimit), 100 /* items */)
 	viper.SetDefault(string(IdentityManagerCacheTTL), "1h")
 
-	i18n.SetLang(GetString(Lang))
+	i18n.SetLang(viper.GetString(string(Lang)))
 }
 
 // ReadConfig initializes the config
 func ReadConfig(cfgFile string) error {
+	keysMutex.Lock() // must only call viper directly here (as we already hold the lock)
+	defer keysMutex.Unlock()
+
 	// Set precedence order for reading config location
 	viper.SetEnvPrefix("firefly")
 	viper.SetEnvKeyReplacer(strings.NewReplacer(".", "_"))
@@ -377,6 +383,9 @@ func ReadConfig(cfgFile string) error {
 }
 
 func MergeConfig(configRecords []*fftypes.ConfigRecord) error {
+	keysMutex.Lock()
+	defer keysMutex.Unlock()
+
 	for _, c := range configRecords {
 		s := viper.New()
 		s.SetConfigType("json")
@@ -422,9 +431,10 @@ func rootKey(k string) RootKey {
 
 // GetKnownKeys gets the known keys
 func GetKnownKeys() []string {
-	keys := make([]string, 0, len(knownKeys))
 	keysMutex.Lock()
 	defer keysMutex.Unlock()
+
+	keys := make([]string, 0, len(knownKeys))
 	for k := range knownKeys {
 		keys = append(keys, k)
 	}
@@ -454,8 +464,7 @@ func NewPluginConfig(prefix string) Prefix {
 }
 
 func (c *configPrefix) prefixKey(k string) string {
-	keysMutex.Lock()
-	defer keysMutex.Unlock()
+	// Caller responsible for holding lock when calling
 	key := c.prefix + k
 	if !knownKeys[key] {
 		panic(fmt.Sprintf("Undefined configuration key '%s'", key))
@@ -506,9 +515,10 @@ func (c *configPrefixArray) ArrayEntry(i int) Prefix {
 }
 
 func (c *configPrefixArray) AddKnownKey(k string, defValue ...interface{}) {
-	// Put a simulated key in the known keys array, to pop into the help info.
 	keysMutex.Lock()
 	defer keysMutex.Unlock()
+
+	// Put a simulated key in the known keys array, to pop into the help info.
 	knownKeys[fmt.Sprintf("%s[].%s", c.base, k)] = true
 	c.defaults[k] = defValue
 }
@@ -531,6 +541,9 @@ func (c *configPrefix) SetDefault(k string, defValue interface{}) {
 }
 
 func GetConfig() fftypes.JSONObject {
+	keysMutex.Lock()
+	defer keysMutex.Unlock()
+
 	conf := fftypes.JSONObject{}
 	_ = viper.Unmarshal(&conf)
 	return conf
@@ -541,6 +554,9 @@ func GetString(key RootKey) string {
 	return root.GetString(string(key))
 }
 func (c *configPrefix) GetString(key string) string {
+	keysMutex.Lock()
+	defer keysMutex.Unlock()
+
 	return viper.GetString(c.prefixKey(key))
 }
 
@@ -549,6 +565,9 @@ func GetStringSlice(key RootKey) []string {
 	return root.GetStringSlice(string(key))
 }
 func (c *configPrefix) GetStringSlice(key string) []string {
+	keysMutex.Lock()
+	defer keysMutex.Unlock()
+
 	return viper.GetStringSlice(c.prefixKey(key))
 }
 
@@ -557,6 +576,9 @@ func GetBool(key RootKey) bool {
 	return root.GetBool(string(key))
 }
 func (c *configPrefix) GetBool(key string) bool {
+	keysMutex.Lock()
+	defer keysMutex.Unlock()
+
 	return viper.GetBool(c.prefixKey(key))
 }
 
@@ -565,6 +587,9 @@ func GetDuration(key RootKey) time.Duration {
 	return root.GetDuration(string(key))
 }
 func (c *configPrefix) GetDuration(key string) time.Duration {
+	keysMutex.Lock()
+	defer keysMutex.Unlock()
+
 	return fftypes.ParseToDuration(viper.GetString(c.prefixKey(key)))
 }
 
@@ -573,7 +598,10 @@ func GetByteSize(key RootKey) int64 {
 	return root.GetByteSize(string(key))
 }
 func (c *configPrefix) GetByteSize(key string) int64 {
-	return fftypes.ParseToByteSize(c.GetString(key))
+	keysMutex.Lock()
+	defer keysMutex.Unlock()
+
+	return fftypes.ParseToByteSize(viper.GetString(c.prefixKey(key)))
 }
 
 // GetUint gets a configuration uint
@@ -581,6 +609,9 @@ func GetUint(key RootKey) uint {
 	return root.GetUint(string(key))
 }
 func (c *configPrefix) GetUint(key string) uint {
+	keysMutex.Lock()
+	defer keysMutex.Unlock()
+
 	return viper.GetUint(c.prefixKey(key))
 }
 
@@ -589,6 +620,9 @@ func GetInt(key RootKey) int {
 	return root.GetInt(string(key))
 }
 func (c *configPrefix) GetInt(key string) int {
+	keysMutex.Lock()
+	defer keysMutex.Unlock()
+
 	return viper.GetInt(c.prefixKey(key))
 }
 
@@ -597,6 +631,9 @@ func GetInt64(key RootKey) int64 {
 	return root.GetInt64(string(key))
 }
 func (c *configPrefix) GetInt64(key string) int64 {
+	keysMutex.Lock()
+	defer keysMutex.Unlock()
+
 	return viper.GetInt64(c.prefixKey(key))
 }
 
@@ -605,6 +642,9 @@ func GetFloat64(key RootKey) float64 {
 	return root.GetFloat64(string(key))
 }
 func (c *configPrefix) GetFloat64(key string) float64 {
+	keysMutex.Lock()
+	defer keysMutex.Unlock()
+
 	return viper.GetFloat64(c.prefixKey(key))
 }
 
@@ -613,6 +653,9 @@ func GetObject(key RootKey) fftypes.JSONObject {
 	return root.GetObject(string(key))
 }
 func (c *configPrefix) GetObject(key string) fftypes.JSONObject {
+	keysMutex.Lock()
+	defer keysMutex.Unlock()
+
 	return fftypes.JSONObject(viper.GetStringMap(c.prefixKey(key)))
 }
 
@@ -621,6 +664,9 @@ func GetObjectArray(key RootKey) fftypes.JSONObjectArray {
 	return root.GetObjectArray(string(key))
 }
 func (c *configPrefix) GetObjectArray(key string) fftypes.JSONObjectArray {
+	keysMutex.Lock()
+	defer keysMutex.Unlock()
+
 	v, _ := fftypes.ToJSONObjectArray(viper.Get(c.prefixKey(key)))
 	return v
 }
@@ -630,6 +676,9 @@ func Get(key RootKey) interface{} {
 	return root.Get(string(key))
 }
 func (c *configPrefix) Get(key string) interface{} {
+	keysMutex.Lock()
+	defer keysMutex.Unlock()
+
 	return viper.Get(c.prefixKey(key))
 }
 
@@ -638,11 +687,17 @@ func Set(key RootKey, value interface{}) {
 	root.Set(string(key), value)
 }
 func (c *configPrefix) Set(key string, value interface{}) {
+	keysMutex.Lock()
+	defer keysMutex.Unlock()
+
 	viper.Set(c.prefixKey(key), value)
 }
 
 // Resolve gives the fully qualified path of a key
 func (c *configPrefix) Resolve(key string) string {
+	keysMutex.Lock()
+	defer keysMutex.Unlock()
+
 	return c.prefixKey(key)
 }
 
diff --git a/internal/config/wsconfig/wsconfig.go b/internal/config/wsconfig/wsconfig.go
index 0b6a0113bc..9ebf76d6e1 100644
--- a/internal/config/wsconfig/wsconfig.go
+++ b/internal/config/wsconfig/wsconfig.go
@@ -1,4 +1,4 @@
-// Copyright © 2021 Kaleido, Inc.
+// Copyright © 2022 Kaleido, Inc.
 //
 // SPDX-License-Identifier: Apache-2.0
 //
@@ -25,6 +25,7 @@ import (
 const (
 	defaultIntialConnectAttempts = 5
 	defaultBufferSize            = "16Kb"
+	defaultHeartbeatInterval     = "30s" // up to a minute to detect a dead connection
 )
 
 const (
@@ -38,6 +39,8 @@ const (
 	WSConfigKeyInitialConnectAttempts = "ws.initialConnectAttempts"
 	// WSConfigKeyPath if set will define the path to connect to - allows sharing of the same URL between HTTP and WebSocket connection info
 	WSConfigKeyPath = "ws.path"
+	// WSConfigHeartbeatInterval is the frequency of ping/pong requests, and also used for the timeout to receive a response to the heartbeat
+	WSConfigHeartbeatInterval = "ws.heartbeatInterval"
 )
 
 // InitPrefix ensures the prefix is initialized for HTTP too, as WS and HTTP
@@ -48,6 +51,7 @@ func InitPrefix(prefix config.KeySet) {
 	prefix.AddKnownKey(WSConfigKeyReadBufferSize, defaultBufferSize)
 	prefix.AddKnownKey(WSConfigKeyInitialConnectAttempts, defaultIntialConnectAttempts)
 	prefix.AddKnownKey(WSConfigKeyPath)
+	prefix.AddKnownKey(WSConfigHeartbeatInterval, defaultHeartbeatInterval)
 }
 
 func GenerateConfigFromPrefix(prefix config.Prefix) *wsclient.WSConfig {
@@ -62,5 +66,6 @@ func GenerateConfigFromPrefix(prefix config.Prefix) *wsclient.WSConfig {
 		HTTPHeaders:            prefix.GetObject(restclient.HTTPConfigHeaders),
 		AuthUsername:           prefix.GetString(restclient.HTTPConfigAuthUsername),
 		AuthPassword:           prefix.GetString(restclient.HTTPConfigAuthPassword),
+		HeartbeatInterval:      prefix.GetDuration(WSConfigHeartbeatInterval),
 	}
 }
diff --git a/internal/events/websockets/websocket_connection.go b/internal/events/websockets/websocket_connection.go
index 79dc29687b..e33dc74775 100644
--- a/internal/events/websockets/websocket_connection.go
+++ b/internal/events/websockets/websocket_connection.go
@@ -1,4 +1,4 @@
-// Copyright © 2021 Kaleido, Inc.
+// Copyright © 2022 Kaleido, Inc.
 //
 // SPDX-License-Identifier: Apache-2.0
 //
@@ -44,6 +44,7 @@ type websocketConnection struct {
 	connID             string
 	sendMessages       chan interface{}
 	senderDone         chan struct{}
+	receiverDone       chan struct{}
 	autoAck            bool
 	started            []*websocketStartedSub
 	inflight           []*fftypes.EventDeliveryResponse
@@ -64,6 +65,7 @@ func newConnection(pCtx context.Context, ws *WebSockets, wsConn *websocket.Conn)
 		connID:       connID,
 		sendMessages: make(chan interface{}),
 		senderDone:   make(chan struct{}),
+		receiverDone: make(chan struct{}),
 	}
 	go wc.sendLoop()
 	go wc.receiveLoop()
@@ -104,11 +106,7 @@ func (wc *websocketConnection) sendLoop() {
 	defer wc.close()
 	for {
 		select {
-		case msg, ok := <-wc.sendMessages:
-			if !ok {
-				l.Debugf("Sender closing")
-				return
-			}
+		case msg := <-wc.sendMessages:
 			l.Tracef("Sending: %+v", msg)
 			writer, err := wc.wsConn.NextWriter(websocket.TextMessage)
 			if err == nil {
@@ -119,6 +117,9 @@ func (wc *websocketConnection) sendLoop() {
 				l.Errorf("Write failed on socket: %s", err)
 				return
 			}
+		case <-wc.receiverDone:
+			l.Debugf("Sender closing - receiver completed")
+			return
 		case <-wc.ctx.Done():
 			l.Debugf("Sender closing - context cancelled")
 			return
@@ -128,7 +129,7 @@ func (wc *websocketConnection) sendLoop() {
 
 func (wc *websocketConnection) receiveLoop() {
 	l := log.L(wc.ctx)
-	defer close(wc.sendMessages)
+	defer close(wc.receiverDone)
 	for {
 		var msgData []byte
 		var msgHeader fftypes.WSClientActionBase
@@ -361,5 +362,5 @@ func (wc *websocketConnection) close() {
 
 func (wc *websocketConnection) waitClose() {
 	<-wc.senderDone
-	<-wc.sendMessages
+	<-wc.receiverDone
 }
diff --git a/internal/i18n/en_translations.go b/internal/i18n/en_translations.go
index f8b9c0b2d3..9d2950f532 100644
--- a/internal/i18n/en_translations.go
+++ b/internal/i18n/en_translations.go
@@ -1,4 +1,4 @@
-// Copyright © 2021 Kaleido, Inc.
+// Copyright © 2022 Kaleido, Inc.
 //
 // SPDX-License-Identifier: Apache-2.0
 //
@@ -18,205 +18,234 @@ package i18n
 
 //revive:disable
 var (
-	MsgConfigFailed                = ffm("FF10101", "Failed to read config")
-	MsgTBD                         = ffm("FF10102", "TODO: Description")
-	MsgJSONDecodeFailed            = ffm("FF10103", "Failed to decode input JSON")
-	MsgAPIServerStartFailed        = ffm("FF10104", "Unable to start listener on %s: %s")
-	MsgTLSConfigFailed             = ffm("FF10105", "Failed to initialize TLS configuration")
-	MsgInvalidCAFile               = ffm("FF10106", "Invalid CA certificates file")
-	MsgResponseMarshalError        = ffm("FF10107", "Failed to serialize response data", 400)
-	MsgWebsocketClientError        = ffm("FF10108", "Error received from WebSocket client: %s")
-	Msg404NotFound                 = ffm("FF10109", "Not found", 404)
-	MsgUnknownBlockchainPlugin     = ffm("FF10110", "Unknown blockchain plugin: %s")
-	MsgEthconnectRESTErr           = ffm("FF10111", "Error from ethconnect: %s")
-	MsgDBInitFailed                = ffm("FF10112", "Database initialization failed")
-	MsgDBQueryBuildFailed          = ffm("FF10113", "Database query builder failed")
-	MsgDBBeginFailed               = ffm("FF10114", "Database begin transaction failed")
-	MsgDBQueryFailed               = ffm("FF10115", "Database query failed")
-	MsgDBInsertFailed              = ffm("FF10116", "Database insert failed")
-	MsgDBUpdateFailed              = ffm("FF10117", "Database update failed")
-	MsgDBDeleteFailed              = ffm("FF10118", "Database delete failed")
-	MsgDBCommitFailed              = ffm("FF10119", "Database commit failed")
-	MsgDBMissingJoin               = ffm("FF10120", "Database missing expected join entry in table '%s' for id '%s'")
-	MsgDBReadErr                   = ffm("FF10121", "Database resultset read error from table '%s'")
-	MsgUnknownDatabasePlugin       = ffm("FF10122", "Unknown database plugin '%s'")
-	MsgNullDataReferenceID         = ffm("FF10123", "Data id is null in message data reference %d")
-	MsgDupDataReferenceID          = ffm("FF10124", "Duplicate data ID in message '%s'")
-	MsgScanFailed                  = ffm("FF10125", "Failed to restore type '%T' into '%T'")
-	MsgUnregisteredBatchType       = ffm("FF10126", "Unregistered batch type '%s'")
-	MsgBatchDispatchTimeout        = ffm("FF10127", "Timed out dispatching work to batch")
-	MsgInitializationNilDepError   = ffm("FF10128", "Initialization error due to unmet dependency")
-	MsgNilResponseNon204           = ffm("FF10129", "No output from API call")
-	MsgInvalidContentType          = ffm("FF10130", "Invalid content type", 415)
-	MsgInvalidName                 = ffm("FF10131", "Field '%s' must be 1-64 characters, including alphanumerics (a-zA-Z0-9), dot (.), dash (-) and underscore (_), and must start/end in an alphanumeric", 400)
-	MsgUnknownFieldValue           = ffm("FF10132", "Unknown %s '%v'", 400)
-	MsgDataNotFound                = ffm("FF10133", "Data not found for message %s", 400)
-	MsgUnknownPublicStoragePlugin  = ffm("FF10134", "Unknown Public Storage plugin '%s'")
-	MsgIPFSHashDecodeFailed        = ffm("FF10135", "Failed to decode IPFS hash into 32byte value '%s'")
-	MsgIPFSRESTErr                 = ffm("FF10136", "Error from IPFS: %s")
-	MsgSerializationFailed         = ffm("FF10137", "Serialization failed")
-	MsgMissingPluginConfig         = ffm("FF10138", "Missing configuration '%s' for %s")
-	MsgMissingDataHashIndex        = ffm("FF10139", "Missing data hash for index '%d' in message", 400)
-	MsgMissingRequiredField        = ffm("FF10140", "Field '%s' is required", 400)
-	MsgInvalidEthAddress           = ffm("FF10141", "Supplied ethereum address is invalid", 400)
-	MsgInvalidUUID                 = ffm("FF10142", "Invalid UUID supplied", 400)
-	Msg404NoResult                 = ffm("FF10143", "No result found", 404)
-	MsgNilDataReferenceSealFail    = ffm("FF10144", "Invalid message: nil data reference at index %d", 400)
-	MsgDupDataReferenceSealFail    = ffm("FF10145", "Invalid message: duplicate data reference at index %d", 400)
-	MsgVerifyFailedInvalidHashes   = ffm("FF10146", "Invalid message: hashes do not match Hash=%s Expected=%s DataHash=%s DataHashExpected=%s", 400)
-	MsgVerifyFailedNilHashes       = ffm("FF10147", "Invalid message: nil hashes", 400)
-	MsgInvalidFilterField          = ffm("FF10148", "Unknown filter '%s'", 400)
-	MsgInvalidValueForFilterField  = ffm("FF10149", "Unable to parse value for filter '%s'", 400)
-	MsgUnsupportedSQLOpInFilter    = ffm("FF10150", "No SQL mapping implemented for filter operator '%s'", 400)
-	MsgJSONObjectParseFailed       = ffm("FF10151", "Failed to parse '%s' as JSON")
-	MsgFilterParamDesc             = ffm("FF10152", "Data filter field. Prefixes supported: > >= < <= @ ^ ! !@ !^")
-	MsgSuccessResponse             = ffm("FF10153", "Success")
-	MsgFilterSortDesc              = ffm("FF10154", "Sort field. For multi-field sort use comma separated values (or multiple query values) with '-' prefix for descending")
-	MsgFilterDescendingDesc        = ffm("FF10155", "Descending sort order (overrides all fields in a multi-field sort)")
-	MsgFilterSkipDesc              = ffm("FF10156", "The number of records to skip (max: %d). Unsuitable for bulk operations")
-	MsgFilterLimitDesc             = ffm("FF10157", "The maximum number of records to return (max: %d)")
-	MsgContextCanceled             = ffm("FF10158", "Context cancelled")
-	MsgWSSendTimedOut              = ffm("FF10159", "Websocket send timed out")
-	MsgWSClosing                   = ffm("FF10160", "Websocket closing")
-	MsgWSConnectFailed             = ffm("FF10161", "Websocket connect failed")
-	MsgInvalidURL                  = ffm("FF10162", "Invalid URL: '%s'")
-	MsgDBMigrationFailed           = ffm("FF10163", "Database migration failed")
-	MsgHashMismatch                = ffm("FF10164", "Hash mismatch")
-	MsgTimeParseFail               = ffm("FF10165", "Cannot parse time as RFC3339, Unix, or UnixNano: '%s'", 400)
-	MsgDefaultNamespaceNotFound    = ffm("FF10166", "namespaces.default '%s' must be included in the namespaces.predefined configuration")
-	MsgDurationParseFail           = ffm("FF10167", "Unable to parse '%s' as duration string, or millisecond number", 400)
-	MsgEventTypesParseFail         = ffm("FF10168", "Unable to parse list of event types", 400)
-	MsgUnknownEventType            = ffm("FF10169", "Unknown event type '%s'", 400)
-	MsgIDMismatch                  = ffm("FF10170", "ID mismatch")
-	MsgRegexpCompileFailed         = ffm("FF10171", "Unable to compile '%s' regexp '%s'")
-	MsgUnknownEventTransportPlugin = ffm("FF10172", "Unknown event transport plugin: %s")
-	MsgWSConnectionNotActive       = ffm("FF10173", "Websocket connection '%s' no longer active")
-	MsgWSSubAlreadyInFlight        = ffm("FF10174", "Websocket subscription '%s' already has a message in flight")
-	MsgWSMsgSubNotMatched          = ffm("FF10175", "Acknowledgment does not match an inflight event + subscription")
-	MsgWSClientSentInvalidData     = ffm("FF10176", "Invalid data")
-	MsgWSClientUnknownAction       = ffm("FF10177", "Unknown action '%s'")
-	MsgWSInvalidStartAction        = ffm("FF10178", "A start action must set namespace and either a name or ephemeral=true")
-	MsgWSAutoAckChanged            = ffm("FF10179", "The autoack option must be set consistently on all start requests")
-	MsgWSAutoAckEnabled            = ffm("FF10180", "The autoack option is enabled on this connection")
-	MsgConnSubscriptionNotStarted  = ffm("FF10181", "Subscription %v is not started on connection")
-	MsgDispatcherClosing           = ffm("FF10182", "Event dispatcher closing")
-	MsgMaxFilterSkip               = ffm("FF10183", "You have reached the maximum pagination limit for this query (%d)")
-	MsgMaxFilterLimit              = ffm("FF10184", "Your query exceeds the maximum filter limit (%d)")
-	MsgAPIServerStaticFail         = ffm("FF10185", "An error occurred loading static content", 500)
-	MsgEventListenerClosing        = ffm("FF10186", "Event listener closing")
-	MsgNamespaceNotExist           = ffm("FF10187", "Namespace does not exist")
-	MsgFieldTooLong                = ffm("FF10188", "Field '%s' maximum length is %d", 400)
-	MsgInvalidSubscription         = ffm("FF10189", "Invalid subscription", 400)
-	MsgMismatchedTransport         = ffm("FF10190", "Connection ID '%s' appears not to be unique between transport '%s' and '%s'", 400)
-	MsgInvalidFirstEvent           = ffm("FF10191", "Invalid firstEvent definition - must be 'newest','oldest' or a sequence number", 400)
-	MsgNumberMustBeGreaterEqual    = ffm("FF10192", "Number must be greater than or equal to %d", 400)
-	MsgAlreadyExists               = ffm("FF10193", "A %s with name '%s:%s' already exists", 409)
-	MsgJSONValidatorBadRef         = ffm("FF10194", "Cannot use JSON validator for data with type '%s' and validator reference '%v'", 400)
-	MsgDatatypeNotFound            = ffm("FF10195", "Datatype '%v' not found", 400)
-	MsgSchemaLoadFailed            = ffm("FF10196", "Datatype '%s' schema invalid", 400)
-	MsgDataCannotBeValidated       = ffm("FF10197", "Data cannot be validated", 400)
-	MsgJSONDataInvalidPerSchema    = ffm("FF10198", "Data does not conform to the JSON schema of datatype '%s': %s", 400)
-	MsgDataValueIsNull             = ffm("FF10199", "Data value is null", 400)
-	MsgUnknownValidatorType        = ffm("FF10200", "Unknown validator type: '%s'", 400)
-	MsgDataInvalidHash             = ffm("FF10201", "Invalid data: hashes do not match Hash=%s Expected=%s", 400)
-	MsgSystemNSDescription         = ffm("FF10202", "FireFly system namespace")
-	MsgNilID                       = ffm("FF10203", "ID is nil")
-	MsgDataReferenceUnresolvable   = ffm("FF10204", "Data reference %d cannot be resolved", 400)
-	MsgDataMissing                 = ffm("FF10205", "Data entry %d has neither 'id' to refer to existing data, or 'value' to include in-line JSON data", 400)
-	MsgAuthorInvalid               = ffm("FF10206", "Invalid author specified", 400)
-	MsgNoTransaction               = ffm("FF10207", "Message does not have a transaction", 404)
-	MsgBatchNotSet                 = ffm("FF10208", "Message does not have an assigned batch", 404)
-	MsgBatchNotFound               = ffm("FF10209", "Batch '%s' not found for message", 500)
-	MsgBatchTXNotSet               = ffm("FF10210", "Batch '%s' does not have an assigned transaction", 404)
-	MsgOwnerMissing                = ffm("FF10211", "Owner missing", 400)
-	MsgUnknownIdentityPlugin       = ffm("FF10212", "Unknown Identity plugin '%s'")
-	MsgUnknownDataExchangePlugin   = ffm("FF10213", "Unknown Data Exchange plugin '%s'")
-	MsgParentIdentityNotFound      = ffm("FF10214", "Organization with identity '%s' not found in identity chain for %s '%s'")
-	MsgInvalidSigningIdentity      = ffm("FF10215", "Invalid signing identity")
-	MsgNodeAndOrgIDMustBeSet       = ffm("FF10216", "node.name, org.name and org.key must be configured first", 409)
-	MsgBlobStreamingFailed         = ffm("FF10217", "Blob streaming terminated with error", 500)
-	MsgMultiPartFormReadError      = ffm("FF10218", "Error reading multi-part form input", 400)
-	MsgGroupMustHaveMembers        = ffm("FF10219", "Group must have at least one member", 400)
-	MsgEmptyMemberIdentity         = ffm("FF10220", "Identity is blank in member %d")
-	MsgEmptyMemberNode             = ffm("FF10221", "Node is blank in member %d")
-	MsgDuplicateMember             = ffm("FF10222", "Member %d is a duplicate org+node combination")
-	MsgOrgNotFound                 = ffm("FF10223", "Org with name or identity '%s' not found", 400)
-	MsgNodeNotFound                = ffm("FF10224", "Node with name or identity '%s' not found", 400)
-	MsgLocalNodeResolveFailed      = ffm("FF10225", "Unable to find local node to add to group. Check the status API to confirm the node is registered", 500)
-	MsgGroupNotFound               = ffm("FF10226", "Group '%s' not found", 404)
-	MsgTooManyItems                = ffm("FF10227", "Maximum number of %s items is %d (supplied=%d)", 400)
-	MsgDuplicateArrayEntry         = ffm("FF10228", "Duplicate %s at index %d: '%s'", 400)
-	MsgDXRESTErr                   = ffm("FF10229", "Error from data exchange: %s")
-	MsgGroupInvalidHash            = ffm("FF10230", "Invalid group: hashes do not match Hash=%s Expected=%s", 400)
-	MsgInvalidHex                  = ffm("FF10231", "Invalid hex supplied", 400)
-	MsgInvalidWrongLenB32          = ffm("FF10232", "Byte length must be 32 (64 hex characters)", 400)
-	MsgNodeNotFoundInOrg           = ffm("FF10233", "Unable to find any nodes owned by org '%s', or parent orgs", 400)
-	MsgFilterAscendingDesc         = ffm("FF10234", "Ascending sort order (overrides all fields in a multi-field sort)")
-	MsgPreInitCheckFailed          = ffm("FF10235", "Pre-initialization has not yet been completed. Add config records with the admin API complete initialization and reset the node")
-	MsgFieldsAfterFile             = ffm("FF10236", "Additional form field sent after file in multi-part form (ignored): '%s'", 400)
-	MsgDXBadResponse               = ffm("FF10237", "Unexpected '%s' in data exchange response: %s")
-	MsgDXBadHash                   = ffm("FF10238", "Unexpected hash returned from data exchange upload. Hash=%s Expected=%s")
-	MsgBlobNotFound                = ffm("FF10239", "No blob has been uploaded or confirmed received, with hash=%s", 404)
-	MsgDownloadBlobFailed          = ffm("FF10240", "Error download blob with reference '%s' from local data exchange")
-	MsgDataDoesNotHaveBlob         = ffm("FF10241", "Data does not have a blob attachment", 404)
-	MsgWebhookURLEmpty             = ffm("FF10242", "Webhook subscription option 'url' cannot be empty", 400)
-	MsgWebhookInvalidStringMap     = ffm("FF10243", "Webhook subscription option '%s' must be map of string values. %s=%T", 400)
-	MsgWebsocketsNoData            = ffm("FF10244", "Websockets subscriptions do not support streaming the full data payload, just the references (withData must be false)", 400)
-	MsgWebhooksWithData            = ffm("FF10245", "Webhook subscriptions require the full data payload (withData must be true)", 400)
-	MsgWebhooksOptURL              = ffm("FF10246", "Webhook url to invoke. Can be relative if a base URL is set in the webhook plugin config")
-	MsgWebhooksOptMethod           = ffm("FF10247", "Webhook method to invoke. Default=POST")
-	MsgWebhooksOptJSON             = ffm("FF10248", "Whether to assume the response body is JSON, regardless of the returned Content-Type")
-	MsgWebhooksOptReply            = ffm("FF10249", "Whether to automatically send a reply event, using the body returned by the webhook")
-	MsgWebhooksOptHeaders          = ffm("FF10250", "Static headers to set on the webhook request")
-	MsgWebhooksOptQuery            = ffm("FF10251", "Static query params to set on the webhook request")
-	MsgWebhooksOptInput            = ffm("FF10252", "A set of options to extract data from the first JSON input data in the incoming message. Only applies if withData=true")
-	MsgWebhooksOptInputQuery       = ffm("FF10253", "A top-level property of the first data input, to use for query parameters")
-	MsgWebhooksOptInputHeaders     = ffm("FF10254", "A top-level property of the first data input, to use for headers")
-	MsgWebhooksOptInputBody        = ffm("FF10255", "A top-level property of the first data input, to use for the request body. Default is the whole first body")
-	MsgWebhooksOptFastAck          = ffm("FF10256", "When true the event will be acknowledged before the webhook is invoked, allowing parallel invocations")
-	MsgWebhooksReplyBadJSON        = ffm("FF10257", "Failed to process reply from webhook as JSON")
-	MsgWebhooksOptReplyTag         = ffm("FF10258", "The tag to set on the reply message")
-	MsgWebhooksOptReplyTx          = ffm("FF10259", "The transaction type to set on the reply message")
-	MsgRequestTimeout              = ffm("FF10260", "The request with id '%s' timed out after %.2fms", 408)
-	MsgRequestReplyTagRequired     = ffm("FF10261", "For request messages 'header.tag' must be set on the request message to route it to a suitable responder", 400)
-	MsgRequestCannotHaveCID        = ffm("FF10262", "For request messages 'header.cid' must be unset", 400)
-	MsgRequestTimeoutDesc          = ffm("FF10263", "Server-side request timeout (millseconds, or set a custom suffix like 10s)")
-	MsgWebhooksOptInputPath        = ffm("FF10264", "A top-level property of the first data input, to use for a path to append with escaping to the webhook path")
-	MsgWebhooksOptInputReplyTx     = ffm("FF10265", "A top-level property of the first data input, to use to dynamically set whether to pin the response (so the requester can choose)")
-	MsgSystemTransportInternal     = ffm("FF10266", "You cannot create subscriptions on the system events transport")
-	MsgFilterCountNotSupported     = ffm("FF10267", "This query does not support generating a count of all results")
-	MsgFilterCountDesc             = ffm("FF10268", "Return a total count as well as items (adds extra database processing)")
-	MsgRejected                    = ffm("FF10269", "Message with ID '%s' was rejected. Please check the FireFly logs for more information")
-	MsgConfirmQueryParam           = ffm("FF10270", "When true the HTTP request blocks until the message is confirmed")
-	MsgRequestMustBePrivate        = ffm("FF10271", "For request messages you must specify a group of private recipients", 400)
-	MsgUnknownTokensPlugin         = ffm("FF10272", "Unknown tokens plugin '%s'", 400)
-	MsgMissingTokensPluginConfig   = ffm("FF10273", "Invalid tokens configuration - name and connector are required", 400)
-	MsgTokensRESTErr               = ffm("FF10274", "Error from tokens service: %s")
-	MsgTokenPoolDuplicate          = ffm("FF10275", "Duplicate token pool")
-	MsgTokenPoolRejected           = ffm("FF10276", "Token pool with ID '%s' was rejected. Please check the FireFly logs for more information")
-	MsgAuthorNotFoundByDID         = ffm("FF10277", "Author could not be resolved via DID '%s'")
-	MsgAuthorOrgNotFoundByName     = ffm("FF10278", "Author organization could not be resolved via name '%s'")
-	MsgAuthorOrgSigningKeyMismatch = ffm("FF10279", "Author organization '%s' is not associated with signing key '%s'")
-	MsgCannotTransferToSelf        = ffm("FF10280", "From and to addresses must be different", 400)
-	MsgLocalOrgLookupFailed        = ffm("FF10281", "Unable resolve the local org by the configured signing key on the node. Please confirm the org is registered with key '%s'", 500)
-	MsgBigIntTooLarge              = ffm("FF10282", "Byte length of serialized integer is too large %d (max=%d)")
-	MsgBigIntParseFailed           = ffm("FF10283", "Failed to parse JSON value '%s' into BigInt")
-	MsgFabconnectRESTErr           = ffm("FF10284", "Error from fabconnect: %s")
-	MsgInvalidIdentity             = ffm("FF10285", "Supplied Fabric signer identity is invalid", 400)
-	MsgFailedToDecodeCertificate   = ffm("FF10286", "Failed to decode certificate: %s", 500)
-	MsgInvalidMessageType          = ffm("FF10287", "Invalid message type - allowed types are %s", 400)
-	MsgNoUUID                      = ffm("FF10288", "Field '%s' must not be a UUID", 400)
-	MsgFetchDataDesc               = ffm("FF10289", "Fetch the data and include it in the messages returned", 400)
-	MsgWSClosed                    = ffm("FF10290", "Websocket closed")
-	MsgTokenTransferFailed         = ffm("FF10291", "Token transfer with ID '%s' failed. Please check the FireFly logs for more information")
-	MsgFieldNotSpecified           = ffm("FF10292", "Field '%s' must be specified", 400)
-	MsgTokenPoolNotConfirmed       = ffm("FF10293", "Token pool is not yet confirmed")
-	MsgHistogramStartTimeParam     = ffm("FF10294", "Start time of the data to be fetched")
-	MsgHistogramEndTimeParam       = ffm("FF10295", "End time of the data to be fetched")
-	MsgHistogramBucketsParam       = ffm("FF10296", "Number of buckets between start time and end time")
-	MsgHistogramCollectionParam    = ffm("FF10297", "Collection to fetch")
-	MsgInvalidNumberOfIntervals    = ffm("FF10298", "Number of time intervals must be between %d and %d", 400)
-	MsgInvalidChartNumberParam     = ffm("FF10299", "Invalid %s. Must be a number.", 400)
-	MsgHistogramInvalidTimes       = ffm("FF10300", "Start time must be before end time", 400)
-	MsgUnsupportedCollection       = ffm("FF10301", "%s collection is not supported", 400)
+	MsgConfigFailed                 = ffm("FF10101", "Failed to read config")
+	MsgTBD                          = ffm("FF10102", "TODO: Description")
+	MsgJSONDecodeFailed             = ffm("FF10103", "Failed to decode input JSON")
+	MsgAPIServerStartFailed         = ffm("FF10104", "Unable to start listener on %s: %s")
+	MsgTLSConfigFailed              = ffm("FF10105", "Failed to initialize TLS configuration")
+	MsgInvalidCAFile                = ffm("FF10106", "Invalid CA certificates file")
+	MsgResponseMarshalError         = ffm("FF10107", "Failed to serialize response data", 400)
+	MsgWebsocketClientError         = ffm("FF10108", "Error received from WebSocket client: %s")
+	Msg404NotFound                  = ffm("FF10109", "Not found", 404)
+	MsgUnknownBlockchainPlugin      = ffm("FF10110", "Unknown blockchain plugin: %s")
+	MsgEthconnectRESTErr            = ffm("FF10111", "Error from ethconnect: %s")
+	MsgDBInitFailed                 = ffm("FF10112", "Database initialization failed")
+	MsgDBQueryBuildFailed           = ffm("FF10113", "Database query builder failed")
+	MsgDBBeginFailed                = ffm("FF10114", "Database begin transaction failed")
+	MsgDBQueryFailed                = ffm("FF10115", "Database query failed")
+	MsgDBInsertFailed               = ffm("FF10116", "Database insert failed")
+	MsgDBUpdateFailed               = ffm("FF10117", "Database update failed")
+	MsgDBDeleteFailed               = ffm("FF10118", "Database delete failed")
+	MsgDBCommitFailed               = ffm("FF10119", "Database commit failed")
+	MsgDBMissingJoin                = ffm("FF10120", "Database missing expected join entry in table '%s' for id '%s'")
+	MsgDBReadErr                    = ffm("FF10121", "Database resultset read error from table '%s'")
+	MsgUnknownDatabasePlugin        = ffm("FF10122", "Unknown database plugin '%s'")
+	MsgNullDataReferenceID          = ffm("FF10123", "Data id is null in message data reference %d")
+	MsgDupDataReferenceID           = ffm("FF10124", "Duplicate data ID in message '%s'")
+	MsgScanFailed                   = ffm("FF10125", "Failed to restore type '%T' into '%T'")
+	MsgUnregisteredBatchType        = ffm("FF10126", "Unregistered batch type '%s'")
+	MsgBatchDispatchTimeout         = ffm("FF10127", "Timed out dispatching work to batch")
+	MsgInitializationNilDepError    = ffm("FF10128", "Initialization error due to unmet dependency")
+	MsgNilResponseNon204            = ffm("FF10129", "No output from API call")
+	MsgInvalidContentType           = ffm("FF10130", "Invalid content type", 415)
+	MsgInvalidName                  = ffm("FF10131", "Field '%s' must be 1-64 characters, including alphanumerics (a-zA-Z0-9), dot (.), dash (-) and underscore (_), and must start/end in an alphanumeric", 400)
+	MsgUnknownFieldValue            = ffm("FF10132", "Unknown %s '%v'", 400)
+	MsgDataNotFound                 = ffm("FF10133", "Data not found for message %s", 400)
+	MsgUnknownPublicStoragePlugin   = ffm("FF10134", "Unknown Public Storage plugin '%s'")
+	MsgIPFSHashDecodeFailed         = ffm("FF10135", "Failed to decode IPFS hash into 32byte value '%s'")
+	MsgIPFSRESTErr                  = ffm("FF10136", "Error from IPFS: %s")
+	MsgSerializationFailed          = ffm("FF10137", "Serialization failed")
+	MsgMissingPluginConfig          = ffm("FF10138", "Missing configuration '%s' for %s")
+	MsgMissingDataHashIndex         = ffm("FF10139", "Missing data hash for index '%d' in message", 400)
+	MsgMissingRequiredField         = ffm("FF10140", "Field '%s' is required", 400)
+	MsgInvalidEthAddress            = ffm("FF10141", "Supplied ethereum address is invalid", 400)
+	MsgInvalidUUID                  = ffm("FF10142", "Invalid UUID supplied", 400)
+	Msg404NoResult                  = ffm("FF10143", "No result found", 404)
+	MsgNilDataReferenceSealFail     = ffm("FF10144", "Invalid message: nil data reference at index %d", 400)
+	MsgDupDataReferenceSealFail     = ffm("FF10145", "Invalid message: duplicate data reference at index %d", 400)
+	MsgVerifyFailedInvalidHashes    = ffm("FF10146", "Invalid message: hashes do not match Hash=%s Expected=%s DataHash=%s DataHashExpected=%s", 400)
+	MsgVerifyFailedNilHashes        = ffm("FF10147", "Invalid message: nil hashes", 400)
+	MsgInvalidFilterField           = ffm("FF10148", "Unknown filter '%s'", 400)
+	MsgInvalidValueForFilterField   = ffm("FF10149", "Unable to parse value for filter '%s'", 400)
+	MsgUnsupportedSQLOpInFilter     = ffm("FF10150", "No SQL mapping implemented for filter operator '%s'", 400)
+	MsgJSONObjectParseFailed        = ffm("FF10151", "Failed to parse '%s' as JSON")
+	MsgFilterParamDesc              = ffm("FF10152", "Data filter field. Prefixes supported: > >= < <= @ ^ ! !@ !^")
+	MsgSuccessResponse              = ffm("FF10153", "Success")
+	MsgFilterSortDesc               = ffm("FF10154", "Sort field. For multi-field sort use comma separated values (or multiple query values) with '-' prefix for descending")
+	MsgFilterDescendingDesc         = ffm("FF10155", "Descending sort order (overrides all fields in a multi-field sort)")
+	MsgFilterSkipDesc               = ffm("FF10156", "The number of records to skip (max: %d). Unsuitable for bulk operations")
+	MsgFilterLimitDesc              = ffm("FF10157", "The maximum number of records to return (max: %d)")
+	MsgContextCanceled              = ffm("FF10158", "Context cancelled")
+	MsgWSSendTimedOut               = ffm("FF10159", "Websocket send timed out")
+	MsgWSClosing                    = ffm("FF10160", "Websocket closing")
+	MsgWSConnectFailed              = ffm("FF10161", "Websocket connect failed")
+	MsgInvalidURL                   = ffm("FF10162", "Invalid URL: '%s'")
+	MsgDBMigrationFailed            = ffm("FF10163", "Database migration failed")
+	MsgHashMismatch                 = ffm("FF10164", "Hash mismatch")
+	MsgTimeParseFail                = ffm("FF10165", "Cannot parse time as RFC3339, Unix, or UnixNano: '%s'", 400)
+	MsgDefaultNamespaceNotFound     = ffm("FF10166", "namespaces.default '%s' must be included in the namespaces.predefined configuration")
+	MsgDurationParseFail            = ffm("FF10167", "Unable to parse '%s' as duration string, or millisecond number", 400)
+	MsgEventTypesParseFail          = ffm("FF10168", "Unable to parse list of event types", 400)
+	MsgUnknownEventType             = ffm("FF10169", "Unknown event type '%s'", 400)
+	MsgIDMismatch                   = ffm("FF10170", "ID mismatch")
+	MsgRegexpCompileFailed          = ffm("FF10171", "Unable to compile '%s' regexp '%s'")
+	MsgUnknownEventTransportPlugin  = ffm("FF10172", "Unknown event transport plugin: %s")
+	MsgWSConnectionNotActive        = ffm("FF10173", "Websocket connection '%s' no longer active")
+	MsgWSSubAlreadyInFlight         = ffm("FF10174", "Websocket subscription '%s' already has a message in flight")
+	MsgWSMsgSubNotMatched           = ffm("FF10175", "Acknowledgment does not match an inflight event + subscription")
+	MsgWSClientSentInvalidData      = ffm("FF10176", "Invalid data")
+	MsgWSClientUnknownAction        = ffm("FF10177", "Unknown action '%s'")
+	MsgWSInvalidStartAction         = ffm("FF10178", "A start action must set namespace and either a name or ephemeral=true")
+	MsgWSAutoAckChanged             = ffm("FF10179", "The autoack option must be set consistently on all start requests")
+	MsgWSAutoAckEnabled             = ffm("FF10180", "The autoack option is enabled on this connection")
+	MsgConnSubscriptionNotStarted   = ffm("FF10181", "Subscription %v is not started on connection")
+	MsgDispatcherClosing            = ffm("FF10182", "Event dispatcher closing")
+	MsgMaxFilterSkip                = ffm("FF10183", "You have reached the maximum pagination limit for this query (%d)")
+	MsgMaxFilterLimit               = ffm("FF10184", "Your query exceeds the maximum filter limit (%d)")
+	MsgAPIServerStaticFail          = ffm("FF10185", "An error occurred loading static content", 500)
+	MsgEventListenerClosing         = ffm("FF10186", "Event listener closing")
+	MsgNamespaceNotExist            = ffm("FF10187", "Namespace does not exist")
+	MsgFieldTooLong                 = ffm("FF10188", "Field '%s' maximum length is %d", 400)
+	MsgInvalidSubscription          = ffm("FF10189", "Invalid subscription", 400)
+	MsgMismatchedTransport          = ffm("FF10190", "Connection ID '%s' appears not to be unique between transport '%s' and '%s'", 400)
+	MsgInvalidFirstEvent            = ffm("FF10191", "Invalid firstEvent definition - must be 'newest','oldest' or a sequence number", 400)
+	MsgNumberMustBeGreaterEqual     = ffm("FF10192", "Number must be greater than or equal to %d", 400)
+	MsgAlreadyExists                = ffm("FF10193", "A %s with name '%s:%s' already exists", 409)
+	MsgJSONValidatorBadRef          = ffm("FF10194", "Cannot use JSON validator for data with type '%s' and validator reference '%v'", 400)
+	MsgDatatypeNotFound             = ffm("FF10195", "Datatype '%v' not found", 400)
+	MsgSchemaLoadFailed             = ffm("FF10196", "Datatype '%s' schema invalid", 400)
+	MsgDataCannotBeValidated        = ffm("FF10197", "Data cannot be validated", 400)
+	MsgJSONDataInvalidPerSchema     = ffm("FF10198", "Data does not conform to the JSON schema of datatype '%s': %s", 400)
+	MsgDataValueIsNull              = ffm("FF10199", "Data value is null", 400)
+	MsgUnknownValidatorType         = ffm("FF10200", "Unknown validator type: '%s'", 400)
+	MsgDataInvalidHash              = ffm("FF10201", "Invalid data: hashes do not match Hash=%s Expected=%s", 400)
+	MsgSystemNSDescription          = ffm("FF10202", "FireFly system namespace")
+	MsgNilID                        = ffm("FF10203", "ID is nil")
+	MsgDataReferenceUnresolvable    = ffm("FF10204", "Data reference %d cannot be resolved", 400)
+	MsgDataMissing                  = ffm("FF10205", "Data entry %d has neither 'id' to refer to existing data, or 'value' to include in-line JSON data", 400)
+	MsgAuthorInvalid                = ffm("FF10206", "Invalid author specified", 400)
+	MsgNoTransaction                = ffm("FF10207", "Message does not have a transaction", 404)
+	MsgBatchNotSet                  = ffm("FF10208", "Message does not have an assigned batch", 404)
+	MsgBatchNotFound                = ffm("FF10209", "Batch '%s' not found for message", 500)
+	MsgBatchTXNotSet                = ffm("FF10210", "Batch '%s' does not have an assigned transaction", 404)
+	MsgOwnerMissing                 = ffm("FF10211", "Owner missing", 400)
+	MsgUnknownIdentityPlugin        = ffm("FF10212", "Unknown Identity plugin '%s'")
+	MsgUnknownDataExchangePlugin    = ffm("FF10213", "Unknown Data Exchange plugin '%s'")
+	MsgParentIdentityNotFound       = ffm("FF10214", "Organization with identity '%s' not found in identity chain for %s '%s'")
+	MsgInvalidSigningIdentity       = ffm("FF10215", "Invalid signing identity")
+	MsgNodeAndOrgIDMustBeSet        = ffm("FF10216", "node.name, org.name and org.identity must be configured first", 409)
+	MsgBlobStreamingFailed          = ffm("FF10217", "Blob streaming terminated with error", 500)
+	MsgMultiPartFormReadError       = ffm("FF10218", "Error reading multi-part form input", 400)
+	MsgGroupMustHaveMembers         = ffm("FF10219", "Group must have at least one member", 400)
+	MsgEmptyMemberIdentity          = ffm("FF10220", "Identity is blank in member %d")
+	MsgEmptyMemberNode              = ffm("FF10221", "Node is blank in member %d")
+	MsgDuplicateMember              = ffm("FF10222", "Member %d is a duplicate org+node combination")
+	MsgOrgNotFound                  = ffm("FF10223", "Org with name or identity '%s' not found", 400)
+	MsgNodeNotFound                 = ffm("FF10224", "Node with name or identity '%s' not found", 400)
+	MsgLocalNodeResolveFailed       = ffm("FF10225", "Unable to find local node to add to group. Check the status API to confirm the node is registered", 500)
+	MsgGroupNotFound                = ffm("FF10226", "Group '%s' not found", 404)
+	MsgTooManyItems                 = ffm("FF10227", "Maximum number of %s items is %d (supplied=%d)", 400)
+	MsgDuplicateArrayEntry          = ffm("FF10228", "Duplicate %s at index %d: '%s'", 400)
+	MsgDXRESTErr                    = ffm("FF10229", "Error from data exchange: %s")
+	MsgGroupInvalidHash             = ffm("FF10230", "Invalid group: hashes do not match Hash=%s Expected=%s", 400)
+	MsgInvalidHex                   = ffm("FF10231", "Invalid hex supplied", 400)
+	MsgInvalidWrongLenB32           = ffm("FF10232", "Byte length must be 32 (64 hex characters)", 400)
+	MsgNodeNotFoundInOrg            = ffm("FF10233", "Unable to find any nodes owned by org '%s', or parent orgs", 400)
+	MsgFilterAscendingDesc          = ffm("FF10234", "Ascending sort order (overrides all fields in a multi-field sort)")
+	MsgPreInitCheckFailed           = ffm("FF10235", "Pre-initialization has not yet been completed. Add config records with the admin API complete initialization and reset the node")
+	MsgFieldsAfterFile              = ffm("FF10236", "Additional form field sent after file in multi-part form (ignored): '%s'", 400)
+	MsgDXBadResponse                = ffm("FF10237", "Unexpected '%s' in data exchange response: %s")
+	MsgDXBadHash                    = ffm("FF10238", "Unexpected hash returned from data exchange upload. Hash=%s Expected=%s")
+	MsgBlobNotFound                 = ffm("FF10239", "No blob has been uploaded or confirmed received, with hash=%s", 404)
+	MsgDownloadBlobFailed           = ffm("FF10240", "Error download blob with reference '%s' from local data exchange")
+	MsgDataDoesNotHaveBlob          = ffm("FF10241", "Data does not have a blob attachment", 404)
+	MsgWebhookURLEmpty              = ffm("FF10242", "Webhook subscription option 'url' cannot be empty", 400)
+	MsgWebhookInvalidStringMap      = ffm("FF10243", "Webhook subscription option '%s' must be map of string values. %s=%T", 400)
+	MsgWebsocketsNoData             = ffm("FF10244", "Websockets subscriptions do not support streaming the full data payload, just the references (withData must be false)", 400)
+	MsgWebhooksWithData             = ffm("FF10245", "Webhook subscriptions require the full data payload (withData must be true)", 400)
+	MsgWebhooksOptURL               = ffm("FF10246", "Webhook url to invoke. Can be relative if a base URL is set in the webhook plugin config")
+	MsgWebhooksOptMethod            = ffm("FF10247", "Webhook method to invoke. Default=POST")
+	MsgWebhooksOptJSON              = ffm("FF10248", "Whether to assume the response body is JSON, regardless of the returned Content-Type")
+	MsgWebhooksOptReply             = ffm("FF10249", "Whether to automatically send a reply event, using the body returned by the webhook")
+	MsgWebhooksOptHeaders           = ffm("FF10250", "Static headers to set on the webhook request")
+	MsgWebhooksOptQuery             = ffm("FF10251", "Static query params to set on the webhook request")
+	MsgWebhooksOptInput             = ffm("FF10252", "A set of options to extract data from the first JSON input data in the incoming message. Only applies if withData=true")
+	MsgWebhooksOptInputQuery        = ffm("FF10253", "A top-level property of the first data input, to use for query parameters")
+	MsgWebhooksOptInputHeaders      = ffm("FF10254", "A top-level property of the first data input, to use for headers")
+	MsgWebhooksOptInputBody         = ffm("FF10255", "A top-level property of the first data input, to use for the request body. Default is the whole first body")
+	MsgWebhooksOptFastAck           = ffm("FF10256", "When true the event will be acknowledged before the webhook is invoked, allowing parallel invocations")
+	MsgWebhooksReplyBadJSON         = ffm("FF10257", "Failed to process reply from webhook as JSON")
+	MsgWebhooksOptReplyTag          = ffm("FF10258", "The tag to set on the reply message")
+	MsgWebhooksOptReplyTx           = ffm("FF10259", "The transaction type to set on the reply message")
+	MsgRequestTimeout               = ffm("FF10260", "The request with id '%s' timed out after %.2fms", 408)
+	MsgRequestReplyTagRequired      = ffm("FF10261", "For request messages 'header.tag' must be set on the request message to route it to a suitable responder", 400)
+	MsgRequestCannotHaveCID         = ffm("FF10262", "For request messages 'header.cid' must be unset", 400)
+	MsgRequestTimeoutDesc           = ffm("FF10263", "Server-side request timeout (millseconds, or set a custom suffix like 10s)")
+	MsgWebhooksOptInputPath         = ffm("FF10264", "A top-level property of the first data input, to use for a path to append with escaping to the webhook path")
+	MsgWebhooksOptInputReplyTx      = ffm("FF10265", "A top-level property of the first data input, to use to dynamically set whether to pin the response (so the requester can choose)")
+	MsgSystemTransportInternal      = ffm("FF10266", "You cannot create subscriptions on the system events transport")
+	MsgFilterCountNotSupported      = ffm("FF10267", "This query does not support generating a count of all results")
+	MsgFilterCountDesc              = ffm("FF10268", "Return a total count as well as items (adds extra database processing)")
+	MsgRejected                     = ffm("FF10269", "Message with ID '%s' was rejected. Please check the FireFly logs for more information")
+	MsgConfirmQueryParam            = ffm("FF10270", "When true the HTTP request blocks until the message is confirmed")
+	MsgRequestMustBePrivate         = ffm("FF10271", "For request messages you must specify a group of private recipients", 400)
+	MsgUnknownTokensPlugin          = ffm("FF10272", "Unknown tokens plugin '%s'", 400)
+	MsgMissingTokensPluginConfig    = ffm("FF10273", "Invalid tokens configuration - name and connector are required", 400)
+	MsgTokensRESTErr                = ffm("FF10274", "Error from tokens service: %s")
+	MsgTokenPoolDuplicate           = ffm("FF10275", "Duplicate token pool")
+	MsgTokenPoolRejected            = ffm("FF10276", "Token pool with ID '%s' was rejected. Please check the FireFly logs for more information")
+	MsgAuthorNotFoundByDID          = ffm("FF10277", "Author could not be resolved via DID '%s'")
+	MsgAuthorOrgNotFoundByName      = ffm("FF10278", "Author organization could not be resolved via name '%s'")
+	MsgAuthorOrgSigningKeyMismatch  = ffm("FF10279", "Author organization '%s' is not associated with signing key '%s'")
+	MsgCannotTransferToSelf         = ffm("FF10280", "From and to addresses must be different", 400)
+	MsgLocalOrgLookupFailed         = ffm("FF10281", "Unable resolve the local org by the configured signing key on the node. Please confirm the org is registered with key '%s'", 500)
+	MsgBigIntTooLarge               = ffm("FF10282", "Byte length of serialized integer is too large %d (max=%d)")
+	MsgBigIntParseFailed            = ffm("FF10283", "Failed to parse JSON value '%s' into BigInt")
+	MsgFabconnectRESTErr            = ffm("FF10284", "Error from fabconnect: %s")
+	MsgInvalidIdentity              = ffm("FF10285", "Supplied Fabric signer identity is invalid", 400)
+	MsgFailedToDecodeCertificate    = ffm("FF10286", "Failed to decode certificate: %s", 500)
+	MsgInvalidMessageType           = ffm("FF10287", "Invalid message type - allowed types are %s", 400)
+	MsgNoUUID                       = ffm("FF10288", "Field '%s' must not be a UUID", 400)
+	MsgFetchDataDesc                = ffm("FF10289", "Fetch the data and include it in the messages returned", 400)
+	MsgWSClosed                     = ffm("FF10290", "Websocket closed")
+	MsgTokenTransferFailed          = ffm("FF10291", "Token transfer with ID '%s' failed. Please check the FireFly logs for more information")
+	MsgFieldNotSpecified            = ffm("FF10292", "Field '%s' must be specified", 400)
+	MsgTokenPoolNotConfirmed        = ffm("FF10293", "Token pool is not yet confirmed")
+	MsgHistogramStartTimeParam      = ffm("FF10294", "Start time of the data to be fetched")
+	MsgHistogramEndTimeParam        = ffm("FF10295", "End time of the data to be fetched")
+	MsgHistogramBucketsParam        = ffm("FF10296", "Number of buckets between start time and end time")
+	MsgHistogramCollectionParam     = ffm("FF10297", "Collection to fetch")
+	MsgInvalidNumberOfIntervals     = ffm("FF10298", "Number of time intervals must be between %d and %d", 400)
+	MsgInvalidChartNumberParam      = ffm("FF10299", "Invalid %s. Must be a number.", 400)
+	MsgHistogramInvalidTimes        = ffm("FF10300", "Start time must be before end time", 400)
+	MsgUnsupportedCollection        = ffm("FF10301", "%s collection is not supported", 400)
+	MsgContractInterfaceExists      = ffm("FF10302", "A contract interface already exists in the namespace: '%s' with name: '%s' and version: '%s'", 409)
+	MsgContractInterfaceNotFound    = ffm("FF10303", "Contract interface %s not found", 404)
+	MsgContractMissingInputArgument = ffm("FF10304", "Missing required input argument '%s'", 400)
+	MsgContractWrongInputType       = ffm("FF10305", "Input '%v' is of type '%v' not expected type of '%v'", 400)
+	MsgContractMissingInputField    = ffm("FF10306", "Expected object of type '%v' to contain field named '%v' but it was missing", 400)
+	MsgContractMapInputType         = ffm("FF10307", "Unable to map input type '%v' to known FireFly type - was expecting '%v'", 400)
+	MsgContractByteDecode           = ffm("FF10308", "Unable to decode field '%v' as bytes", 400)
+	MsgContractInternalType         = ffm("FF10309", "Input '%v' of type '%v' is not compatible blockchain internalType of '%v'", 400)
+	MsgContractLocationInvalid      = ffm("FF10310", "Failed to validate contract location: %v", 400)
+	MsgContractParamInvalid         = ffm("FF10311", "Failed to validate contract param: %v", 400)
+	MsgContractSubscriptionExists   = ffm("FF10312", "A contract subscription already exists in the namespace: '%s' with name: '%s'", 409)
+	MsgContractMethodNotSet         = ffm("FF10313", "Method not specified on invoke contract request", 400)
+	MsgContractNoMethodSignature    = ffm("FF10314", "Method signature is required if interfaceID is absent", 400)
+	MsgContractMethodResolveError   = ffm("FF10315", "Unable to resolve contract method: %s", 400)
+	MsgContractLocationExists       = ffm("FF10316", "The contract location cannot be changed after it is created", 400)
+	MsgSubscriptionNoEvent          = ffm("FF10317", "An eventId or in-line event definition must be supplied when subscribing", 400)
+	MsgSubscriptionEventNotFound    = ffm("FF10318", "No event was found in namespace '%s' with id '%s'", 400)
+	MsgEventNameMustBeSet           = ffm("FF10319", "Event name must be set", 400)
+	MsgMethodNameMustBeSet          = ffm("FF10320", "Method name must be set", 400)
+	MsgContractEventResolveError    = ffm("FF10321", "Unable to resolve contract event", 400)
+	MsgQueryOpUnsupportedMod        = ffm("FF10322", "Operation '%s' on '%s' does not support modifiers", 400)
+	MsgDXBadSize                    = ffm("FF10323", "Unexpected size returned from data exchange upload. Size=%d Expected=%d")
+	MsgBlobMismatchSealingData      = ffm("FF10324", "Blob mismatch when sealing data")
+	MsgFieldTypeNoStringMatching    = ffm("FF10325", "Field '%s' of type '%s' does not support partial or case-insensitive string matching", 400)
+	MsgFieldMatchNoNull             = ffm("FF10326", "Comparison operator for field '%s' cannot accept a null value", 400)
+	MsgTooLargeBroadcast            = ffm("FF10327", "Message size %.2fkb is too large for the max broadcast batch size of %.2fkb", 400)
+	MsgTooLargePrivate              = ffm("FF10328", "Message size %.2fkb is too large for the max private message size of %.2fkb", 400)
+	MsgManifestMismatch             = ffm("FF10329", "Manifest mismatch overriding '%s' status as failure: '%s'", 400)
+	MsgWSHeartbeatTimeout           = ffm("FF10330", "Websocket heartbeat timed out after %.2fms", 500)
 )
diff --git a/pkg/wsclient/wsclient.go b/pkg/wsclient/wsclient.go
index 7d30c68be6..677f649997 100644
--- a/pkg/wsclient/wsclient.go
+++ b/pkg/wsclient/wsclient.go
@@ -1,4 +1,4 @@
-// Copyright © 2021 Kaleido, Inc.
+// Copyright © 2022 Kaleido, Inc.
 //
 // SPDX-License-Identifier: Apache-2.0
 //
@@ -23,6 +23,7 @@ import (
 	"io/ioutil"
 	"net/http"
 	"net/url"
+	"sync"
 	"time"
 
 	"github.com/gorilla/websocket"
@@ -43,6 +44,7 @@ type WSConfig struct {
 	AuthUsername           string             `json:"authUsername,omitempty"`
 	AuthPassword           string             `json:"authPassword,omitempty"`
 	HTTPHeaders            fftypes.JSONObject `json:"headers,omitempty"`
+	HeartbeatInterval      time.Duration      `json:"heartbeatInterval,omitempty"`
 }
 
 type WSClient interface {
@@ -68,6 +70,10 @@ type wsClient struct {
 	sendDone             chan []byte
 	closing              chan struct{}
 	afterConnect         WSPostConnectHandler
+	heartbeatInterval    time.Duration
+	heartbeatMux         sync.Mutex
+	activePingSent       *time.Time
+	lastPingCompleted    time.Time
 }
 
 // WSPostConnectHandler will be called after every connect/reconnect. Can send data over ws, but must not block listening for data on the ws.
@@ -97,6 +103,7 @@ func New(ctx context.Context, config *WSConfig, afterConnect WSPostConnectHandle
 		send:                 make(chan []byte),
 		closing:              make(chan struct{}),
 		afterConnect:         afterConnect,
+		heartbeatInterval:    config.HeartbeatInterval,
 	}
 	for k, v := range config.HTTPHeaders {
 		if vs, ok := v.(string); ok {
@@ -159,6 +166,21 @@ func (w *wsClient) Send(ctx context.Context, message []byte) error {
 	}
 }
 
+func (w *wsClient) heartbeatTimeout(ctx context.Context) (context.Context, context.CancelFunc) {
+	if w.heartbeatInterval > 0 {
+		w.heartbeatMux.Lock()
+		baseTime := w.lastPingCompleted
+		if w.activePingSent != nil {
+			// We're waiting for a pong
+			baseTime = *w.activePingSent
+		}
+		waitTime := w.heartbeatInterval - time.Since(baseTime) // if negative, will pop immediately
+		w.heartbeatMux.Unlock()
+		return context.WithTimeout(ctx, waitTime)
+	}
+	return context.WithCancel(ctx)
+}
+
 func buildWSUrl(ctx context.Context, config *WSConfig) (string, error) {
 	u, err := url.Parse(config.HTTPURL)
 	if err != nil {
@@ -195,6 +217,8 @@ func (w *wsClient) connect(initial bool) error {
 			l.Warnf("WS %s connect attempt %d failed [%d]: %s", w.url, attempt, status, string(b))
 			return !initial || attempt > w.initialRetryAttempts, i18n.WrapError(w.ctx, err, i18n.MsgWSConnectFailed)
 		}
+		w.pongReceivedOrReset(false)
+		w.wsconn.SetPongHandler(w.pongHandler)
 		l.Infof("WS %s connected", w.url)
 		return false, nil
 	})
@@ -226,22 +250,64 @@ func (w *wsClient) readLoop() {
 	}
 }
 
+func (w *wsClient) pongHandler(appData string) error {
+	w.pongReceivedOrReset(true)
+	return nil
+}
+
+func (w *wsClient) pongReceivedOrReset(isPong bool) {
+	w.heartbeatMux.Lock()
+	defer w.heartbeatMux.Unlock()
+
+	if isPong && w.activePingSent != nil {
+		log.L(w.ctx).Debugf("WS %s heartbeat completed (pong) after %.2fms", w.url, float64(time.Since(*w.activePingSent))/float64(time.Millisecond))
+	}
+	w.lastPingCompleted = time.Now() // in new connection case we still want to consider now the time we completed the ping
+	w.activePingSent = nil
+}
+
+func (w *wsClient) heartbeatCheck() error {
+	w.heartbeatMux.Lock()
+	defer w.heartbeatMux.Unlock()
+
+	if w.activePingSent != nil {
+		return i18n.NewError(w.ctx, i18n.MsgWSHeartbeatTimeout, float64(time.Since(*w.activePingSent))/float64(time.Millisecond))
+	}
+	log.L(w.ctx).Debugf("WS %s heartbeat timer popped (ping) after %.2fms", w.url, float64(time.Since(w.lastPingCompleted))/float64(time.Millisecond))
+	now := time.Now()
+	w.activePingSent = &now
+	return nil
+}
+
 func (w *wsClient) sendLoop(receiverDone chan struct{}) {
 	l := log.L(w.ctx)
 	defer close(w.sendDone)
 
-	for {
+	disconnecting := false
+	for !disconnecting {
+		timeoutContext, timeoutCancel := w.heartbeatTimeout(w.ctx)
+
 		select {
 		case message := <-w.send:
 			l.Tracef("WS sending: %s", message)
 			if err := w.wsconn.WriteMessage(websocket.TextMessage, message); err != nil {
 				l.Errorf("WS %s send failed: %s", w.url, err)
-				return
+				disconnecting = true
+			}
+		case <-timeoutContext.Done():
+			if err := w.heartbeatCheck(); err != nil {
+				l.Errorf("WS %s closing: %s", w.url, err)
+				disconnecting = true
+			} else if err := w.wsconn.WriteMessage(websocket.PingMessage, []byte{}); err != nil {
+				l.Errorf("WS %s heartbeat send failed: %s", w.url, err)
+				disconnecting = true
 			}
 		case <-receiverDone:
 			l.Debugf("WS %s send loop exiting", w.url)
-			return
+			disconnecting = true
 		}
+
+		timeoutCancel()
 	}
 }
 
diff --git a/pkg/wsclient/wsclient_test.go b/pkg/wsclient/wsclient_test.go
index 1fe45688a9..84eff63684 100644
--- a/pkg/wsclient/wsclient_test.go
+++ b/pkg/wsclient/wsclient_test.go
@@ -22,6 +22,7 @@ import (
 	"net/http"
 	"net/http/httptest"
 	"testing"
+	"time"
 
 	"github.com/gorilla/websocket"
 	"github.com/stretchr/testify/assert"
@@ -47,13 +48,14 @@ func TestWSClientE2E(t *testing.T) {
 
 	wsConfig.HTTPURL = url
 	wsConfig.WSKeyPath = "/test"
+	wsConfig.HeartbeatInterval = 50 * time.Millisecond
 
-	wsClient, err := New(context.Background(), wsConfig, afterConnect)
+	wsc, err := New(context.Background(), wsConfig, afterConnect)
 	assert.NoError(t, err)
 
 	//  Change the settings and connect
-	wsClient.SetURL(wsClient.URL() + "/updated")
-	err = wsClient.Connect()
+	wsc.SetURL(wsc.URL() + "/updated")
+	err = wsc.Connect()
 	assert.NoError(t, err)
 
 	// Receive the message automatically sent in afterConnect
@@ -62,19 +64,25 @@ func TestWSClientE2E(t *testing.T) {
 
 	// Tell the unit test server to send us a reply, and confirm it
 	fromServer <- `some data from server`
-	reply := <-wsClient.Receive()
+	reply := <-wsc.Receive()
 	assert.Equal(t, `some data from server`, string(reply))
 
 	// Send some data back
-	err = wsClient.Send(context.Background(), []byte(`some data to server`))
+	err = wsc.Send(context.Background(), []byte(`some data to server`))
 	assert.NoError(t, err)
 
 	// Check the sevrer got it
 	message2 := <-toServer
 	assert.Equal(t, `some data to server`, message2)
 
+	// Check heartbeating works
+	beforePing := time.Now()
+	for wsc.(*wsClient).lastPingCompleted.Before(beforePing) {
+		time.Sleep(10 * time.Millisecond)
+	}
+
 	// Close the client
-	wsClient.Close()
+	wsc.Close()
 
 }
 
@@ -276,3 +284,42 @@ func TestWSSendInstructClose(t *testing.T) {
 	w.sendLoop(receiverClosed)
 	<-w.sendDone
 }
+
+func TestHeartbeatTimedout(t *testing.T) {
+
+	now := time.Now()
+	w := &wsClient{
+		ctx:               context.Background(),
+		sendDone:          make(chan []byte),
+		heartbeatInterval: 1 * time.Microsecond,
+		activePingSent:    &now,
+	}
+
+	w.sendLoop(make(chan struct{}))
+
+}
+
+func TestHeartbeatSendFailed(t *testing.T) {
+
+	_, _, url, close := NewTestWSServer(func(req *http.Request) {})
+	defer close()
+
+	wsc, err := New(context.Background(), &WSConfig{HTTPURL: url}, func(ctx context.Context, w WSClient) error { return nil })
+	assert.NoError(t, err)
+	defer wsc.Close()
+
+	err = wsc.Connect()
+	assert.NoError(t, err)
+
+	// Close and use the underlying wsconn to drive a failure to send a heartbeat
+	wsc.(*wsClient).wsconn.Close()
+	w := &wsClient{
+		ctx:               context.Background(),
+		sendDone:          make(chan []byte),
+		heartbeatInterval: 1 * time.Microsecond,
+		wsconn:            wsc.(*wsClient).wsconn,
+	}
+
+	w.sendLoop(make(chan struct{}))
+
+}
diff --git a/pkg/wsclient/wstestserver.go b/pkg/wsclient/wstestserver.go
index dc0fef7676..a487c03d9f 100644
--- a/pkg/wsclient/wstestserver.go
+++ b/pkg/wsclient/wstestserver.go
@@ -1,4 +1,4 @@
-// Copyright © 2021 Kaleido, Inc.
+// Copyright © 2022 Kaleido, Inc.
 //
 // SPDX-License-Identifier: Apache-2.0
 //