VOL-1867 move simulated olt from voltha-go to voltha-simolt-adapter
Sourced from voltha-go commit 251a11c0ffe60512318a644cd6ce0dc4e12f4018
Change-Id: I8e7ee4da1fed739b3c461917301d2729a79307f5
diff --git a/vendor/github.com/opencord/voltha-go/kafka/kafka_inter_container_library.go b/vendor/github.com/opencord/voltha-go/kafka/kafka_inter_container_library.go
new file mode 100644
index 0000000..56b5fa1
--- /dev/null
+++ b/vendor/github.com/opencord/voltha-go/kafka/kafka_inter_container_library.go
@@ -0,0 +1,825 @@
+/*
+ * Copyright 2018-present Open Networking Foundation
+
+ * 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
+
+ * http://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 kafka
+
+import (
+ "context"
+ "errors"
+ "fmt"
+ "github.com/golang/protobuf/proto"
+ "github.com/golang/protobuf/ptypes"
+ "github.com/golang/protobuf/ptypes/any"
+ "github.com/google/uuid"
+ "github.com/opencord/voltha-go/common/log"
+ ic "github.com/opencord/voltha-protos/go/inter_container"
+ "reflect"
+ "strings"
+ "sync"
+ "time"
+)
+
+// Initialize the logger - gets the default until the main function setup the logger
+func init() {
+ log.AddPackage(log.JSON, log.DebugLevel, nil)
+}
+
+const (
+ DefaultMaxRetries = 3
+ DefaultRequestTimeout = 10000 // 10000 milliseconds - to handle a wider latency range
+)
+
+const (
+ TransactionKey = "transactionID"
+ FromTopic = "fromTopic"
+)
+
+// requestHandlerChannel represents an interface associated with a channel. Whenever, an event is
+// obtained from that channel, this interface is invoked. This is used to handle
+// async requests into the Core via the kafka messaging bus
+type requestHandlerChannel struct {
+ requesthandlerInterface interface{}
+ ch <-chan *ic.InterContainerMessage
+}
+
+// transactionChannel represents a combination of a topic and a channel onto which a response received
+// on the kafka bus will be sent to
+type transactionChannel struct {
+ topic *Topic
+ ch chan *ic.InterContainerMessage
+}
+
+// InterContainerProxy represents the messaging proxy
+type InterContainerProxy struct {
+ kafkaHost string
+ kafkaPort int
+ DefaultTopic *Topic
+ defaultRequestHandlerInterface interface{}
+ deviceDiscoveryTopic *Topic
+ kafkaClient Client
+ doneCh chan int
+
+ // This map is used to map a topic to an interface and channel. When a request is received
+ // on that channel (registered to the topic) then that interface is invoked.
+ topicToRequestHandlerChannelMap map[string]*requestHandlerChannel
+ lockTopicRequestHandlerChannelMap sync.RWMutex
+
+ // This map is used to map a channel to a response topic. This channel handles all responses on that
+ // channel for that topic and forward them to the appropriate consumers channel, using the
+ // transactionIdToChannelMap.
+ topicToResponseChannelMap map[string]<-chan *ic.InterContainerMessage
+ lockTopicResponseChannelMap sync.RWMutex
+
+ // This map is used to map a transaction to a consumers channel. This is used whenever a request has been
+ // sent out and we are waiting for a response.
+ transactionIdToChannelMap map[string]*transactionChannel
+ lockTransactionIdToChannelMap sync.RWMutex
+}
+
+type InterContainerProxyOption func(*InterContainerProxy)
+
+func InterContainerHost(host string) InterContainerProxyOption {
+ return func(args *InterContainerProxy) {
+ args.kafkaHost = host
+ }
+}
+
+func InterContainerPort(port int) InterContainerProxyOption {
+ return func(args *InterContainerProxy) {
+ args.kafkaPort = port
+ }
+}
+
+func DefaultTopic(topic *Topic) InterContainerProxyOption {
+ return func(args *InterContainerProxy) {
+ args.DefaultTopic = topic
+ }
+}
+
+func DeviceDiscoveryTopic(topic *Topic) InterContainerProxyOption {
+ return func(args *InterContainerProxy) {
+ args.deviceDiscoveryTopic = topic
+ }
+}
+
+func RequestHandlerInterface(handler interface{}) InterContainerProxyOption {
+ return func(args *InterContainerProxy) {
+ args.defaultRequestHandlerInterface = handler
+ }
+}
+
+func MsgClient(client Client) InterContainerProxyOption {
+ return func(args *InterContainerProxy) {
+ args.kafkaClient = client
+ }
+}
+
+func NewInterContainerProxy(opts ...InterContainerProxyOption) (*InterContainerProxy, error) {
+ proxy := &InterContainerProxy{
+ kafkaHost: DefaultKafkaHost,
+ kafkaPort: DefaultKafkaPort,
+ }
+
+ for _, option := range opts {
+ option(proxy)
+ }
+
+ // Create the locks for all the maps
+ proxy.lockTopicRequestHandlerChannelMap = sync.RWMutex{}
+ proxy.lockTransactionIdToChannelMap = sync.RWMutex{}
+ proxy.lockTopicResponseChannelMap = sync.RWMutex{}
+
+ return proxy, nil
+}
+
+func (kp *InterContainerProxy) Start() error {
+ log.Info("Starting-Proxy")
+
+ // Kafka MsgClient should already have been created. If not, output fatal error
+ if kp.kafkaClient == nil {
+ log.Fatal("kafka-client-not-set")
+ }
+
+ // Create the Done channel
+ kp.doneCh = make(chan int, 1)
+
+ // Start the kafka client
+ if err := kp.kafkaClient.Start(); err != nil {
+ log.Errorw("Cannot-create-kafka-proxy", log.Fields{"error": err})
+ return err
+ }
+
+ // Create the topic to response channel map
+ kp.topicToResponseChannelMap = make(map[string]<-chan *ic.InterContainerMessage)
+ //
+ // Create the transactionId to Channel Map
+ kp.transactionIdToChannelMap = make(map[string]*transactionChannel)
+
+ // Create the topic to request channel map
+ kp.topicToRequestHandlerChannelMap = make(map[string]*requestHandlerChannel)
+
+ return nil
+}
+
+func (kp *InterContainerProxy) Stop() {
+ log.Info("stopping-intercontainer-proxy")
+ kp.doneCh <- 1
+ // TODO : Perform cleanup
+ kp.kafkaClient.Stop()
+ //kp.deleteAllTopicRequestHandlerChannelMap()
+ //kp.deleteAllTopicResponseChannelMap()
+ //kp.deleteAllTransactionIdToChannelMap()
+}
+
+// DeviceDiscovered publish the discovered device onto the kafka messaging bus
+func (kp *InterContainerProxy) DeviceDiscovered(deviceId string, deviceType string, parentId string, publisher string) error {
+ log.Debugw("sending-device-discovery-msg", log.Fields{"deviceId": deviceId})
+ // Simple validation
+ if deviceId == "" || deviceType == "" {
+ log.Errorw("invalid-parameters", log.Fields{"id": deviceId, "type": deviceType})
+ return errors.New("invalid-parameters")
+ }
+ // Create the device discovery message
+ header := &ic.Header{
+ Id: uuid.New().String(),
+ Type: ic.MessageType_DEVICE_DISCOVERED,
+ FromTopic: kp.DefaultTopic.Name,
+ ToTopic: kp.deviceDiscoveryTopic.Name,
+ Timestamp: time.Now().UnixNano(),
+ }
+ body := &ic.DeviceDiscovered{
+ Id: deviceId,
+ DeviceType: deviceType,
+ ParentId: parentId,
+ Publisher: publisher,
+ }
+
+ var marshalledData *any.Any
+ var err error
+ if marshalledData, err = ptypes.MarshalAny(body); err != nil {
+ log.Errorw("cannot-marshal-request", log.Fields{"error": err})
+ return err
+ }
+ msg := &ic.InterContainerMessage{
+ Header: header,
+ Body: marshalledData,
+ }
+
+ // Send the message
+ if err := kp.kafkaClient.Send(msg, kp.deviceDiscoveryTopic); err != nil {
+ log.Errorw("cannot-send-device-discovery-message", log.Fields{"error": err})
+ return err
+ }
+ return nil
+}
+
+// InvokeRPC is used to send a request to a given topic
+func (kp *InterContainerProxy) InvokeRPC(ctx context.Context, rpc string, toTopic *Topic, replyToTopic *Topic,
+ waitForResponse bool, key string, kvArgs ...*KVArg) (bool, *any.Any) {
+
+ // If a replyToTopic is provided then we use it, otherwise just use the default toTopic. The replyToTopic is
+ // typically the device ID.
+ responseTopic := replyToTopic
+ if responseTopic == nil {
+ responseTopic = kp.DefaultTopic
+ }
+
+ // Encode the request
+ protoRequest, err := encodeRequest(rpc, toTopic, responseTopic, key, kvArgs...)
+ if err != nil {
+ log.Warnw("cannot-format-request", log.Fields{"rpc": rpc, "error": err})
+ return false, nil
+ }
+
+ // Subscribe for response, if needed, before sending request
+ var ch <-chan *ic.InterContainerMessage
+ if waitForResponse {
+ var err error
+ if ch, err = kp.subscribeForResponse(*responseTopic, protoRequest.Header.Id); err != nil {
+ log.Errorw("failed-to-subscribe-for-response", log.Fields{"error": err, "toTopic": toTopic.Name})
+ }
+ }
+
+ // Send request - if the topic is formatted with a device Id then we will send the request using a
+ // specific key, hence ensuring a single partition is used to publish the request. This ensures that the
+ // subscriber on that topic will receive the request in the order it was sent. The key used is the deviceId.
+ //key := GetDeviceIdFromTopic(*toTopic)
+ log.Debugw("sending-msg", log.Fields{"rpc": rpc, "toTopic": toTopic, "replyTopic": responseTopic, "key": key, "xId": protoRequest.Header.Id})
+ go kp.kafkaClient.Send(protoRequest, toTopic, key)
+
+ if waitForResponse {
+ // Create a child context based on the parent context, if any
+ var cancel context.CancelFunc
+ childCtx := context.Background()
+ if ctx == nil {
+ ctx, cancel = context.WithTimeout(context.Background(), DefaultRequestTimeout*time.Millisecond)
+ } else {
+ childCtx, cancel = context.WithTimeout(ctx, DefaultRequestTimeout*time.Millisecond)
+ }
+ defer cancel()
+
+ // Wait for response as well as timeout or cancellation
+ // Remove the subscription for a response on return
+ defer kp.unSubscribeForResponse(protoRequest.Header.Id)
+ select {
+ case msg, ok := <-ch:
+ if !ok {
+ log.Warnw("channel-closed", log.Fields{"rpc": rpc, "replyTopic": replyToTopic.Name})
+ protoError := &ic.Error{Reason: "channel-closed"}
+ var marshalledArg *any.Any
+ if marshalledArg, err = ptypes.MarshalAny(protoError); err != nil {
+ return false, nil // Should never happen
+ }
+ return false, marshalledArg
+ }
+ log.Debugw("received-response", log.Fields{"rpc": rpc, "msgHeader": msg.Header})
+ var responseBody *ic.InterContainerResponseBody
+ var err error
+ if responseBody, err = decodeResponse(msg); err != nil {
+ log.Errorw("decode-response-error", log.Fields{"error": err})
+ }
+ return responseBody.Success, responseBody.Result
+ case <-ctx.Done():
+ log.Debugw("context-cancelled", log.Fields{"rpc": rpc, "ctx": ctx.Err()})
+ // pack the error as proto any type
+ protoError := &ic.Error{Reason: ctx.Err().Error()}
+ var marshalledArg *any.Any
+ if marshalledArg, err = ptypes.MarshalAny(protoError); err != nil {
+ return false, nil // Should never happen
+ }
+ return false, marshalledArg
+ case <-childCtx.Done():
+ log.Debugw("context-cancelled", log.Fields{"rpc": rpc, "ctx": childCtx.Err()})
+ // pack the error as proto any type
+ protoError := &ic.Error{Reason: childCtx.Err().Error()}
+ var marshalledArg *any.Any
+ if marshalledArg, err = ptypes.MarshalAny(protoError); err != nil {
+ return false, nil // Should never happen
+ }
+ return false, marshalledArg
+ case <-kp.doneCh:
+ log.Infow("received-exit-signal", log.Fields{"toTopic": toTopic.Name, "rpc": rpc})
+ return true, nil
+ }
+ }
+ return true, nil
+}
+
+// SubscribeWithRequestHandlerInterface allows a caller to assign a target object to be invoked automatically
+// when a message is received on a given topic
+func (kp *InterContainerProxy) SubscribeWithRequestHandlerInterface(topic Topic, handler interface{}) error {
+
+ // Subscribe to receive messages for that topic
+ var ch <-chan *ic.InterContainerMessage
+ var err error
+ if ch, err = kp.kafkaClient.Subscribe(&topic); err != nil {
+ //if ch, err = kp.Subscribe(topic); err != nil {
+ log.Errorw("failed-to-subscribe", log.Fields{"error": err, "topic": topic.Name})
+ return err
+ }
+
+ kp.defaultRequestHandlerInterface = handler
+ kp.addToTopicRequestHandlerChannelMap(topic.Name, &requestHandlerChannel{requesthandlerInterface: handler, ch: ch})
+ // Launch a go routine to receive and process kafka messages
+ go kp.waitForMessages(ch, topic, handler)
+
+ return nil
+}
+
+// SubscribeWithDefaultRequestHandler allows a caller to add a topic to an existing target object to be invoked automatically
+// when a message is received on a given topic. So far there is only 1 target registered per microservice
+func (kp *InterContainerProxy) SubscribeWithDefaultRequestHandler(topic Topic, initialOffset int64) error {
+ // Subscribe to receive messages for that topic
+ var ch <-chan *ic.InterContainerMessage
+ var err error
+ if ch, err = kp.kafkaClient.Subscribe(&topic, &KVArg{Key: Offset, Value: initialOffset}); err != nil {
+ log.Errorw("failed-to-subscribe", log.Fields{"error": err, "topic": topic.Name})
+ return err
+ }
+ kp.addToTopicRequestHandlerChannelMap(topic.Name, &requestHandlerChannel{requesthandlerInterface: kp.defaultRequestHandlerInterface, ch: ch})
+
+ // Launch a go routine to receive and process kafka messages
+ go kp.waitForMessages(ch, topic, kp.defaultRequestHandlerInterface)
+
+ return nil
+}
+
+func (kp *InterContainerProxy) UnSubscribeFromRequestHandler(topic Topic) error {
+ return kp.deleteFromTopicRequestHandlerChannelMap(topic.Name)
+}
+
+// setupTopicResponseChannelMap sets up single consumers channel that will act as a broadcast channel for all
+// responses from that topic.
+func (kp *InterContainerProxy) setupTopicResponseChannelMap(topic string, arg <-chan *ic.InterContainerMessage) {
+ kp.lockTopicResponseChannelMap.Lock()
+ defer kp.lockTopicResponseChannelMap.Unlock()
+ if _, exist := kp.topicToResponseChannelMap[topic]; !exist {
+ kp.topicToResponseChannelMap[topic] = arg
+ }
+}
+
+func (kp *InterContainerProxy) isTopicSubscribedForResponse(topic string) bool {
+ kp.lockTopicResponseChannelMap.RLock()
+ defer kp.lockTopicResponseChannelMap.RUnlock()
+ _, exist := kp.topicToResponseChannelMap[topic]
+ return exist
+}
+
+func (kp *InterContainerProxy) deleteFromTopicResponseChannelMap(topic string) error {
+ kp.lockTopicResponseChannelMap.Lock()
+ defer kp.lockTopicResponseChannelMap.Unlock()
+ if _, exist := kp.topicToResponseChannelMap[topic]; exist {
+ // Unsubscribe to this topic first - this will close the subscribed channel
+ var err error
+ if err = kp.kafkaClient.UnSubscribe(&Topic{Name: topic}, kp.topicToResponseChannelMap[topic]); err != nil {
+ log.Errorw("unsubscribing-error", log.Fields{"topic": topic})
+ }
+ delete(kp.topicToResponseChannelMap, topic)
+ return err
+ } else {
+ return errors.New(fmt.Sprintf("%s-Topic-not-found", topic))
+ }
+}
+
+func (kp *InterContainerProxy) deleteAllTopicResponseChannelMap() error {
+ kp.lockTopicResponseChannelMap.Lock()
+ defer kp.lockTopicResponseChannelMap.Unlock()
+ var err error
+ for topic, _ := range kp.topicToResponseChannelMap {
+ // Unsubscribe to this topic first - this will close the subscribed channel
+ if err = kp.kafkaClient.UnSubscribe(&Topic{Name: topic}, kp.topicToResponseChannelMap[topic]); err != nil {
+ log.Errorw("unsubscribing-error", log.Fields{"topic": topic, "error": err})
+ }
+ delete(kp.topicToResponseChannelMap, topic)
+ }
+ return err
+}
+
+func (kp *InterContainerProxy) addToTopicRequestHandlerChannelMap(topic string, arg *requestHandlerChannel) {
+ kp.lockTopicRequestHandlerChannelMap.Lock()
+ defer kp.lockTopicRequestHandlerChannelMap.Unlock()
+ if _, exist := kp.topicToRequestHandlerChannelMap[topic]; !exist {
+ kp.topicToRequestHandlerChannelMap[topic] = arg
+ }
+}
+
+func (kp *InterContainerProxy) deleteFromTopicRequestHandlerChannelMap(topic string) error {
+ kp.lockTopicRequestHandlerChannelMap.Lock()
+ defer kp.lockTopicRequestHandlerChannelMap.Unlock()
+ if _, exist := kp.topicToRequestHandlerChannelMap[topic]; exist {
+ // Close the kafka client client first by unsubscribing to this topic
+ kp.kafkaClient.UnSubscribe(&Topic{Name: topic}, kp.topicToRequestHandlerChannelMap[topic].ch)
+ delete(kp.topicToRequestHandlerChannelMap, topic)
+ return nil
+ } else {
+ return errors.New(fmt.Sprintf("%s-Topic-not-found", topic))
+ }
+}
+
+func (kp *InterContainerProxy) deleteAllTopicRequestHandlerChannelMap() error {
+ kp.lockTopicRequestHandlerChannelMap.Lock()
+ defer kp.lockTopicRequestHandlerChannelMap.Unlock()
+ var err error
+ for topic, _ := range kp.topicToRequestHandlerChannelMap {
+ // Close the kafka client client first by unsubscribing to this topic
+ if err = kp.kafkaClient.UnSubscribe(&Topic{Name: topic}, kp.topicToRequestHandlerChannelMap[topic].ch); err != nil {
+ log.Errorw("unsubscribing-error", log.Fields{"topic": topic, "error": err})
+ }
+ delete(kp.topicToRequestHandlerChannelMap, topic)
+ }
+ return err
+}
+
+func (kp *InterContainerProxy) addToTransactionIdToChannelMap(id string, topic *Topic, arg chan *ic.InterContainerMessage) {
+ kp.lockTransactionIdToChannelMap.Lock()
+ defer kp.lockTransactionIdToChannelMap.Unlock()
+ if _, exist := kp.transactionIdToChannelMap[id]; !exist {
+ kp.transactionIdToChannelMap[id] = &transactionChannel{topic: topic, ch: arg}
+ }
+}
+
+func (kp *InterContainerProxy) deleteFromTransactionIdToChannelMap(id string) {
+ kp.lockTransactionIdToChannelMap.Lock()
+ defer kp.lockTransactionIdToChannelMap.Unlock()
+ if transChannel, exist := kp.transactionIdToChannelMap[id]; exist {
+ // Close the channel first
+ close(transChannel.ch)
+ delete(kp.transactionIdToChannelMap, id)
+ }
+}
+
+func (kp *InterContainerProxy) deleteTopicTransactionIdToChannelMap(id string) {
+ kp.lockTransactionIdToChannelMap.Lock()
+ defer kp.lockTransactionIdToChannelMap.Unlock()
+ for key, value := range kp.transactionIdToChannelMap {
+ if value.topic.Name == id {
+ close(value.ch)
+ delete(kp.transactionIdToChannelMap, key)
+ }
+ }
+}
+
+func (kp *InterContainerProxy) deleteAllTransactionIdToChannelMap() {
+ kp.lockTransactionIdToChannelMap.Lock()
+ defer kp.lockTransactionIdToChannelMap.Unlock()
+ for key, value := range kp.transactionIdToChannelMap {
+ close(value.ch)
+ delete(kp.transactionIdToChannelMap, key)
+ }
+}
+
+func (kp *InterContainerProxy) DeleteTopic(topic Topic) error {
+ // If we have any consumers on that topic we need to close them
+ if err := kp.deleteFromTopicResponseChannelMap(topic.Name); err != nil {
+ log.Errorw("delete-from-topic-responsechannelmap-failed", log.Fields{"error": err})
+ }
+ if err := kp.deleteFromTopicRequestHandlerChannelMap(topic.Name); err != nil {
+ log.Errorw("delete-from-topic-requesthandlerchannelmap-failed", log.Fields{"error": err})
+ }
+ kp.deleteTopicTransactionIdToChannelMap(topic.Name)
+
+ return kp.kafkaClient.DeleteTopic(&topic)
+}
+
+func encodeReturnedValue(returnedVal interface{}) (*any.Any, error) {
+ // Encode the response argument - needs to be a proto message
+ if returnedVal == nil {
+ return nil, nil
+ }
+ protoValue, ok := returnedVal.(proto.Message)
+ if !ok {
+ log.Warnw("response-value-not-proto-message", log.Fields{"error": ok, "returnVal": returnedVal})
+ err := errors.New("response-value-not-proto-message")
+ return nil, err
+ }
+
+ // Marshal the returned value, if any
+ var marshalledReturnedVal *any.Any
+ var err error
+ if marshalledReturnedVal, err = ptypes.MarshalAny(protoValue); err != nil {
+ log.Warnw("cannot-marshal-returned-val", log.Fields{"error": err})
+ return nil, err
+ }
+ return marshalledReturnedVal, nil
+}
+
+func encodeDefaultFailedResponse(request *ic.InterContainerMessage) *ic.InterContainerMessage {
+ responseHeader := &ic.Header{
+ Id: request.Header.Id,
+ Type: ic.MessageType_RESPONSE,
+ FromTopic: request.Header.ToTopic,
+ ToTopic: request.Header.FromTopic,
+ Timestamp: time.Now().Unix(),
+ }
+ responseBody := &ic.InterContainerResponseBody{
+ Success: false,
+ Result: nil,
+ }
+ var marshalledResponseBody *any.Any
+ var err error
+ // Error should never happen here
+ if marshalledResponseBody, err = ptypes.MarshalAny(responseBody); err != nil {
+ log.Warnw("cannot-marshal-failed-response-body", log.Fields{"error": err})
+ }
+
+ return &ic.InterContainerMessage{
+ Header: responseHeader,
+ Body: marshalledResponseBody,
+ }
+
+}
+
+//formatRequest formats a request to send over kafka and returns an InterContainerMessage message on success
+//or an error on failure
+func encodeResponse(request *ic.InterContainerMessage, success bool, returnedValues ...interface{}) (*ic.InterContainerMessage, error) {
+ //log.Debugw("encodeResponse", log.Fields{"success": success, "returnedValues": returnedValues})
+ responseHeader := &ic.Header{
+ Id: request.Header.Id,
+ Type: ic.MessageType_RESPONSE,
+ FromTopic: request.Header.ToTopic,
+ ToTopic: request.Header.FromTopic,
+ KeyTopic: request.Header.KeyTopic,
+ Timestamp: time.Now().UnixNano(),
+ }
+
+ // Go over all returned values
+ var marshalledReturnedVal *any.Any
+ var err error
+ for _, returnVal := range returnedValues {
+ if marshalledReturnedVal, err = encodeReturnedValue(returnVal); err != nil {
+ log.Warnw("cannot-marshal-response-body", log.Fields{"error": err})
+ }
+ break // for now we support only 1 returned value - (excluding the error)
+ }
+
+ responseBody := &ic.InterContainerResponseBody{
+ Success: success,
+ Result: marshalledReturnedVal,
+ }
+
+ // Marshal the response body
+ var marshalledResponseBody *any.Any
+ if marshalledResponseBody, err = ptypes.MarshalAny(responseBody); err != nil {
+ log.Warnw("cannot-marshal-response-body", log.Fields{"error": err})
+ return nil, err
+ }
+
+ return &ic.InterContainerMessage{
+ Header: responseHeader,
+ Body: marshalledResponseBody,
+ }, nil
+}
+
+func CallFuncByName(myClass interface{}, funcName string, params ...interface{}) (out []reflect.Value, err error) {
+ myClassValue := reflect.ValueOf(myClass)
+ // Capitalize the first letter in the funcName to workaround the first capital letters required to
+ // invoke a function from a different package
+ funcName = strings.Title(funcName)
+ m := myClassValue.MethodByName(funcName)
+ if !m.IsValid() {
+ return make([]reflect.Value, 0), fmt.Errorf("method-not-found \"%s\"", funcName)
+ }
+ in := make([]reflect.Value, len(params))
+ for i, param := range params {
+ in[i] = reflect.ValueOf(param)
+ }
+ out = m.Call(in)
+ return
+}
+
+func (kp *InterContainerProxy) addTransactionId(transactionId string, currentArgs []*ic.Argument) []*ic.Argument {
+ arg := &KVArg{
+ Key: TransactionKey,
+ Value: &ic.StrType{Val: transactionId},
+ }
+
+ var marshalledArg *any.Any
+ var err error
+ if marshalledArg, err = ptypes.MarshalAny(&ic.StrType{Val: transactionId}); err != nil {
+ log.Warnw("cannot-add-transactionId", log.Fields{"error": err})
+ return currentArgs
+ }
+ protoArg := &ic.Argument{
+ Key: arg.Key,
+ Value: marshalledArg,
+ }
+ return append(currentArgs, protoArg)
+}
+
+func (kp *InterContainerProxy) addFromTopic(fromTopic string, currentArgs []*ic.Argument) []*ic.Argument {
+ var marshalledArg *any.Any
+ var err error
+ if marshalledArg, err = ptypes.MarshalAny(&ic.StrType{Val: fromTopic}); err != nil {
+ log.Warnw("cannot-add-transactionId", log.Fields{"error": err})
+ return currentArgs
+ }
+ protoArg := &ic.Argument{
+ Key: FromTopic,
+ Value: marshalledArg,
+ }
+ return append(currentArgs, protoArg)
+}
+
+func (kp *InterContainerProxy) handleMessage(msg *ic.InterContainerMessage, targetInterface interface{}) {
+
+ // First extract the header to know whether this is a request - responses are handled by a different handler
+ if msg.Header.Type == ic.MessageType_REQUEST {
+ var out []reflect.Value
+ var err error
+
+ // Get the request body
+ requestBody := &ic.InterContainerRequestBody{}
+ if err = ptypes.UnmarshalAny(msg.Body, requestBody); err != nil {
+ log.Warnw("cannot-unmarshal-request", log.Fields{"error": err})
+ } else {
+ log.Debugw("received-request", log.Fields{"rpc": requestBody.Rpc, "header": msg.Header})
+ // let the callee unpack the arguments as its the only one that knows the real proto type
+ // Augment the requestBody with the message Id as it will be used in scenarios where cores
+ // are set in pairs and competing
+ requestBody.Args = kp.addTransactionId(msg.Header.Id, requestBody.Args)
+
+ // Augment the requestBody with the From topic name as it will be used in scenarios where a container
+ // needs to send an unsollicited message to the currently requested container
+ requestBody.Args = kp.addFromTopic(msg.Header.FromTopic, requestBody.Args)
+
+ out, err = CallFuncByName(targetInterface, requestBody.Rpc, requestBody.Args)
+ if err != nil {
+ log.Warn(err)
+ }
+ }
+ // Response required?
+ if requestBody.ResponseRequired {
+ // If we already have an error before then just return that
+ var returnError *ic.Error
+ var returnedValues []interface{}
+ var success bool
+ if err != nil {
+ returnError = &ic.Error{Reason: err.Error()}
+ returnedValues = make([]interface{}, 1)
+ returnedValues[0] = returnError
+ } else {
+ returnedValues = make([]interface{}, 0)
+ // Check for errors first
+ lastIndex := len(out) - 1
+ if out[lastIndex].Interface() != nil { // Error
+ if goError, ok := out[lastIndex].Interface().(error); ok {
+ returnError = &ic.Error{Reason: goError.Error()}
+ returnedValues = append(returnedValues, returnError)
+ } else { // Should never happen
+ returnError = &ic.Error{Reason: "incorrect-error-returns"}
+ returnedValues = append(returnedValues, returnError)
+ }
+ } else if len(out) == 2 && reflect.ValueOf(out[0].Interface()).IsValid() && reflect.ValueOf(out[0].Interface()).IsNil() {
+ return // Ignore case - when core is in competing mode
+ } else { // Non-error case
+ success = true
+ for idx, val := range out {
+ //log.Debugw("returned-api-response-loop", log.Fields{"idx": idx, "val": val.Interface()})
+ if idx != lastIndex {
+ returnedValues = append(returnedValues, val.Interface())
+ }
+ }
+ }
+ }
+
+ var icm *ic.InterContainerMessage
+ if icm, err = encodeResponse(msg, success, returnedValues...); err != nil {
+ log.Warnw("error-encoding-response-returning-failure-result", log.Fields{"error": err})
+ icm = encodeDefaultFailedResponse(msg)
+ }
+ // To preserve ordering of messages, all messages to a given topic are sent to the same partition
+ // by providing a message key. The key is encoded in the topic name. If the deviceId is not
+ // present then the key will be empty, hence all messages for a given topic will be sent to all
+ // partitions.
+ replyTopic := &Topic{Name: msg.Header.FromTopic}
+ key := msg.Header.KeyTopic
+ log.Debugw("sending-response-to-kafka", log.Fields{"rpc": requestBody.Rpc, "header": icm.Header, "key": key})
+ // TODO: handle error response.
+ go kp.kafkaClient.Send(icm, replyTopic, key)
+ }
+ } else if msg.Header.Type == ic.MessageType_RESPONSE {
+ log.Debugw("response-received", log.Fields{"msg-header": msg.Header})
+ go kp.dispatchResponse(msg)
+ } else {
+ log.Warnw("unsupported-message-received", log.Fields{"msg-header": msg.Header})
+ }
+}
+
+func (kp *InterContainerProxy) waitForMessages(ch <-chan *ic.InterContainerMessage, topic Topic, targetInterface interface{}) {
+ // Wait for messages
+ for msg := range ch {
+ //log.Debugw("request-received", log.Fields{"msg": msg, "topic": topic.Name, "target": targetInterface})
+ go kp.handleMessage(msg, targetInterface)
+ }
+}
+
+func (kp *InterContainerProxy) dispatchResponse(msg *ic.InterContainerMessage) {
+ kp.lockTransactionIdToChannelMap.RLock()
+ defer kp.lockTransactionIdToChannelMap.RUnlock()
+ if _, exist := kp.transactionIdToChannelMap[msg.Header.Id]; !exist {
+ log.Debugw("no-waiting-channel", log.Fields{"transaction": msg.Header.Id})
+ return
+ }
+ kp.transactionIdToChannelMap[msg.Header.Id].ch <- msg
+}
+
+// subscribeForResponse allows a caller to subscribe to a given topic when waiting for a response.
+// This method is built to prevent all subscribers to receive all messages as is the case of the Subscribe
+// API. There is one response channel waiting for kafka messages before dispatching the message to the
+// corresponding waiting channel
+func (kp *InterContainerProxy) subscribeForResponse(topic Topic, trnsId string) (chan *ic.InterContainerMessage, error) {
+ log.Debugw("subscribeForResponse", log.Fields{"topic": topic.Name, "trnsid": trnsId})
+
+ // Create a specific channel for this consumers. We cannot use the channel from the kafkaclient as it will
+ // broadcast any message for this topic to all channels waiting on it.
+ ch := make(chan *ic.InterContainerMessage)
+ kp.addToTransactionIdToChannelMap(trnsId, &topic, ch)
+
+ return ch, nil
+}
+
+func (kp *InterContainerProxy) unSubscribeForResponse(trnsId string) error {
+ log.Debugw("unsubscribe-for-response", log.Fields{"trnsId": trnsId})
+ kp.deleteFromTransactionIdToChannelMap(trnsId)
+ return nil
+}
+
+//formatRequest formats a request to send over kafka and returns an InterContainerMessage message on success
+//or an error on failure
+func encodeRequest(rpc string, toTopic *Topic, replyTopic *Topic, key string, kvArgs ...*KVArg) (*ic.InterContainerMessage, error) {
+ requestHeader := &ic.Header{
+ Id: uuid.New().String(),
+ Type: ic.MessageType_REQUEST,
+ FromTopic: replyTopic.Name,
+ ToTopic: toTopic.Name,
+ KeyTopic: key,
+ Timestamp: time.Now().UnixNano(),
+ }
+ requestBody := &ic.InterContainerRequestBody{
+ Rpc: rpc,
+ ResponseRequired: true,
+ ReplyToTopic: replyTopic.Name,
+ }
+
+ for _, arg := range kvArgs {
+ if arg == nil {
+ // In case the caller sends an array with empty args
+ continue
+ }
+ var marshalledArg *any.Any
+ var err error
+ // ascertain the value interface type is a proto.Message
+ protoValue, ok := arg.Value.(proto.Message)
+ if !ok {
+ log.Warnw("argument-value-not-proto-message", log.Fields{"error": ok, "Value": arg.Value})
+ err := errors.New("argument-value-not-proto-message")
+ return nil, err
+ }
+ if marshalledArg, err = ptypes.MarshalAny(protoValue); err != nil {
+ log.Warnw("cannot-marshal-request", log.Fields{"error": err})
+ return nil, err
+ }
+ protoArg := &ic.Argument{
+ Key: arg.Key,
+ Value: marshalledArg,
+ }
+ requestBody.Args = append(requestBody.Args, protoArg)
+ }
+
+ var marshalledData *any.Any
+ var err error
+ if marshalledData, err = ptypes.MarshalAny(requestBody); err != nil {
+ log.Warnw("cannot-marshal-request", log.Fields{"error": err})
+ return nil, err
+ }
+ request := &ic.InterContainerMessage{
+ Header: requestHeader,
+ Body: marshalledData,
+ }
+ return request, nil
+}
+
+func decodeResponse(response *ic.InterContainerMessage) (*ic.InterContainerResponseBody, error) {
+ // Extract the message body
+ responseBody := ic.InterContainerResponseBody{}
+ if err := ptypes.UnmarshalAny(response.Body, &responseBody); err != nil {
+ log.Warnw("cannot-unmarshal-response", log.Fields{"error": err})
+ return nil, err
+ }
+ //log.Debugw("response-decoded-successfully", log.Fields{"response-status": &responseBody.Success})
+
+ return &responseBody, nil
+
+}