VOL-2087 reorganize and unit test arouterd

Change-Id: Iadacd1829095e8ffde306e5ebf164f4d67196a68
diff --git a/cmd/arouterd/arouterd.go b/cmd/arouterd/arouterd.go
index de469b5..78c8af8 100644
--- a/cmd/arouterd/arouterd.go
+++ b/cmd/arouterd/arouterd.go
@@ -17,398 +17,41 @@
 package main
 
 import (
-	"errors"
 	"flag"
 	"fmt"
-	"google.golang.org/grpc/connectivity"
-	"google.golang.org/grpc/keepalive"
-	"k8s.io/api/core/v1"
-	"math"
+	"github.com/opencord/voltha-api-server/internal/pkg/afrouterd"
+	"github.com/opencord/voltha-go/common/version"
 	"os"
 	"path"
-	"regexp"
-	"strconv"
-	"time"
 
-	"github.com/golang/protobuf/ptypes"
-	"github.com/golang/protobuf/ptypes/empty"
 	"github.com/opencord/voltha-go/common/log"
-	"github.com/opencord/voltha-go/common/version"
-	"github.com/opencord/voltha-go/kafka"
 	pb "github.com/opencord/voltha-protos/go/afrouter"
-	cmn "github.com/opencord/voltha-protos/go/common"
-	ic "github.com/opencord/voltha-protos/go/inter_container"
-	vpb "github.com/opencord/voltha-protos/go/voltha"
 	"golang.org/x/net/context"
-	"google.golang.org/grpc"
-	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
-	"k8s.io/client-go/kubernetes"
-	"k8s.io/client-go/rest"
-	"k8s.io/client-go/tools/clientcmd"
 )
 
-type volthaPod struct {
-	name    string
-	ipAddr  string
-	node    string
-	devIds  map[string]struct{}
-	backend string
-}
+var (
+	instanceID         = afrouterd.GetStrEnv("HOSTNAME", "arouterd001")
+	afrouterApiAddress = afrouterd.GetStrEnv("AFROUTER_API_ADDRESS", "localhost:55554")
+)
 
 type Configuration struct {
 	DisplayVersionOnly *bool
 }
 
-var (
-	// if k8s variables are undefined, will attempt to use in-cluster config
-	k8sApiServer      = getStrEnv("K8S_API_SERVER", "")
-	k8sKubeConfigPath = getStrEnv("K8S_KUBE_CONFIG_PATH", "")
-
-	podNamespace          = getStrEnv("POD_NAMESPACE", "voltha")
-	podLabelSelector      = getStrEnv("POD_LABEL_SELECTOR", "app=rw-core")
-	podAffinityGroupLabel = getStrEnv("POD_AFFINITY_GROUP_LABEL", "affinity-group")
-
-	podGrpcPort = uint64(getIntEnv("POD_GRPC_PORT", 0, math.MaxUint16, 50057))
-
-	afrouterApiAddress = getStrEnv("AFROUTER_API_ADDRESS", "localhost:55554")
-
-	afrouterRouterName    = getStrEnv("AFROUTER_ROUTER_NAME", "vcore")
-	afrouterRouteName     = getStrEnv("AFROUTER_ROUTE_NAME", "dev_manager")
-	afrouterRWClusterName = getStrEnv("AFROUTER_RW_CLUSTER_NAME", "vcore")
-
-	kafkaTopic      = getStrEnv("KAFKA_TOPIC", "AffinityRouter")
-	kafkaClientType = getStrEnv("KAFKA_CLIENT_TYPE", "sarama")
-	kafkaHost       = getStrEnv("KAFKA_HOST", "kafka")
-	kafkaPort       = getIntEnv("KAFKA_PORT", 0, math.MaxUint16, 9092)
-	kafkaInstanceID = getStrEnv("KAFKA_INSTANCE_ID", "arouterd")
-
-	instanceID = getStrEnv("HOSTNAME", "arouterd001")
-)
-
-func getIntEnv(key string, min, max, defaultValue int) int {
-	if val, have := os.LookupEnv(key); have {
-		num, err := strconv.Atoi(val)
-		if err != nil || !(min <= num && num <= max) {
-			panic(fmt.Errorf("%s must be a number in the range [%d, %d]; default: %d", key, min, max, defaultValue))
-		}
-		return num
-	}
-	return defaultValue
-}
-
-func getStrEnv(key, defaultValue string) string {
-	if val, have := os.LookupEnv(key); have {
-		return val
-	}
-	return defaultValue
-}
-
-func newKafkaClient(clientType string, host string, port int, instanceID string) (kafka.Client, error) {
-	log.Infow("kafka-client-type", log.Fields{"client": clientType})
-	switch clientType {
-	case "sarama":
-		return kafka.NewSaramaClient(
-			kafka.Host(host),
-			kafka.Port(port),
-			kafka.ConsumerType(kafka.GroupCustomer),
-			kafka.ProducerReturnOnErrors(true),
-			kafka.ProducerReturnOnSuccess(true),
-			kafka.ProducerMaxRetries(6),
-			kafka.NumPartitions(3),
-			kafka.ConsumerGroupName(instanceID),
-			kafka.ConsumerGroupPrefix(instanceID),
-			kafka.AutoCreateTopic(false),
-			kafka.ProducerFlushFrequency(5),
-			kafka.ProducerRetryBackoff(time.Millisecond*30)), nil
-	}
-	return nil, errors.New("unsupported-client-type")
-}
-
-func k8sClientSet() *kubernetes.Clientset {
-	var config *rest.Config
-	if k8sApiServer != "" || k8sKubeConfigPath != "" {
-		// use combination of URL & local kube-config file
-		c, err := clientcmd.BuildConfigFromFlags(k8sApiServer, k8sKubeConfigPath)
-		if err != nil {
-			panic(err)
-		}
-		config = c
-	} else {
-		// use in-cluster config
-		c, err := rest.InClusterConfig()
-		if err != nil {
-			log.Errorf("Unable to load in-cluster config.  Try setting K8S_API_SERVER and K8S_KUBE_CONFIG_PATH?")
-			panic(err)
-		}
-		config = c
-	}
-	// creates the clientset
-	clientset, err := kubernetes.NewForConfig(config)
-	if err != nil {
-		panic(err)
-	}
-
-	return clientset
-}
-
-func connect(ctx context.Context, addr string) (*grpc.ClientConn, error) {
-	log.Debugf("Trying to connect to %s", addr)
-	conn, err := grpc.DialContext(ctx, addr,
-		grpc.WithInsecure(),
-		grpc.WithBlock(),
-		grpc.WithBackoffMaxDelay(time.Second*5),
-		grpc.WithKeepaliveParams(keepalive.ClientParameters{Time: time.Second * 10, Timeout: time.Second * 5}))
-	if err == nil {
-		log.Debugf("Connection succeeded")
-	}
-	return conn, err
-}
-
-func getVolthaPods(cs *kubernetes.Clientset) ([]*volthaPod, error) {
-	pods, err := cs.CoreV1().Pods(podNamespace).List(metav1.ListOptions{LabelSelector: podLabelSelector})
-	if err != nil {
-		return nil, err
-	}
-
-	var rwPods []*volthaPod
-items:
-	for _, v := range pods.Items {
-		// only pods that are actually running should be considered
-		if v.Status.Phase == v1.PodRunning {
-			for _, condition := range v.Status.Conditions {
-				if condition.Status != v1.ConditionTrue {
-					continue items
-				}
-			}
-
-			if group, have := v.Labels[podAffinityGroupLabel]; have {
-				log.Debugf("Namespace: %s, PodName: %s, PodIP: %s, Host: %s\n", v.Namespace, v.Name, v.Status.PodIP, v.Spec.NodeName)
-				rwPods = append(rwPods, &volthaPod{
-					name:    v.Name,
-					ipAddr:  v.Status.PodIP,
-					node:    v.Spec.NodeName,
-					devIds:  make(map[string]struct{}),
-					backend: afrouterRWClusterName + group,
-				})
-			} else {
-				log.Warnf("Pod %s found matching % without label %", v.Name, podLabelSelector, podAffinityGroupLabel)
-			}
-		}
-	}
-	return rwPods, nil
-}
-
-func reconcilePodDeviceIds(ctx context.Context, pod *volthaPod, ids map[string]struct{}) {
-	ctxTimeout, _ := context.WithTimeout(ctx, time.Second*5)
-	conn, err := connect(ctxTimeout, fmt.Sprintf("%s:%d", pod.ipAddr, podGrpcPort))
-	if err != nil {
-		log.Debugf("Could not reconcile devices from %s, could not connect: %s", pod.name, err)
-		return
-	}
-	defer conn.Close()
-
-	var idList cmn.IDs
-	for k := range ids {
-		idList.Items = append(idList.Items, &cmn.ID{Id: k})
-	}
-
-	client := vpb.NewVolthaServiceClient(conn)
-	_, err = client.ReconcileDevices(ctx, &idList)
-	if err != nil {
-		log.Errorf("Attempt to reconcile ids on pod %s failed: %s", pod.name, err)
-		return
-	}
-}
-
-func queryPodDeviceIds(ctx context.Context, pod *volthaPod) map[string]struct{} {
-	ctxTimeout, _ := context.WithTimeout(ctx, time.Second*5)
-	conn, err := connect(ctxTimeout, fmt.Sprintf("%s:%d", pod.ipAddr, podGrpcPort))
-	if err != nil {
-		log.Debugf("Could not query devices from %s, could not connect: %s", pod.name, err)
-		return nil
-	}
-	defer conn.Close()
-
-	client := vpb.NewVolthaServiceClient(conn)
-	devs, err := client.ListDeviceIds(ctx, &empty.Empty{})
-	if err != nil {
-		log.Error(err)
-		return nil
-	}
-
-	var ret = make(map[string]struct{})
-	for _, dv := range devs.Items {
-		ret[dv.Id] = struct{}{}
-	}
-	return ret
-}
-
-func setAffinity(ctx context.Context, client pb.ConfigurationClient, deviceId string, backend string) {
-	log.Debugf("Configuring backend %s with device id %s \n", backend, deviceId)
-	if res, err := client.SetAffinity(ctx, &pb.Affinity{
-		Router:  afrouterRouterName,
-		Route:   afrouterRouteName,
-		Cluster: afrouterRWClusterName,
-		Backend: backend,
-		Id:      deviceId,
-	}); err != nil {
-		log.Debugf("failed affinity RPC call: %s\n", err)
-	} else {
-		log.Debugf("Result: %v\n", res)
-	}
-}
-
-func monitorDiscovery(kc kafka.Client, ctx context.Context, client pb.ConfigurationClient, ch <-chan *ic.InterContainerMessage, doneCh chan<- struct{}) {
-	defer close(doneCh)
-	defer kc.Stop()
-
-monitorLoop:
-	for {
-		select {
-		case <-ctx.Done():
-			break monitorLoop
-		case msg := <-ch:
-			log.Debug("Received a device discovery notification")
-			device := &ic.DeviceDiscovered{}
-			if err := ptypes.UnmarshalAny(msg.Body, device); err != nil {
-				log.Errorf("Could not unmarshal received notification %v", msg)
-			} else {
-				// somewhat hackish solution, backend is known from the first digit found in the publisher name
-				group := regexp.MustCompile(`\d`).FindString(device.Publisher)
-				if group != "" {
-					// set the affinity of the discovered device
-					setAffinity(ctx, client, device.Id, afrouterRWClusterName+group)
-				} else {
-					log.Error("backend is unknown")
-				}
-			}
-		}
-	}
-}
-
-func startDiscoveryMonitor(ctx context.Context, client pb.ConfigurationClient) (<-chan struct{}, error) {
-	doneCh := make(chan struct{})
-	// Connect to kafka for discovery events
-	kc, err := newKafkaClient(kafkaClientType, kafkaHost, kafkaPort, kafkaInstanceID)
-	if err != nil {
-		panic(err)
-	}
-
-	for {
-		if err := kc.Start(); err != nil {
-			log.Error("Could not connect to kafka")
-		} else {
-			break
-		}
-		select {
-		case <-ctx.Done():
-			close(doneCh)
-			return doneCh, errors.New("GRPC context done")
-
-		case <-time.After(5 * time.Second):
-		}
-	}
-	ch, err := kc.Subscribe(&kafka.Topic{Name: kafkaTopic})
-	if err != nil {
-		log.Errorf("Could not subscribe to the '%s' channel, discovery disabled", kafkaTopic)
-		close(doneCh)
-		kc.Stop()
-		return doneCh, err
-	}
-
-	go monitorDiscovery(kc, ctx, client, ch, doneCh)
-	return doneCh, nil
-}
-
-// coreMonitor polls the list of devices from all RW cores, pushes these devices
-// into the affinity router, and ensures that all cores in a backend have their devices synced
-func coreMonitor(ctx context.Context, client pb.ConfigurationClient, clientset *kubernetes.Clientset) {
-	// map[backend]map[deviceId]struct{}
-	deviceOwnership := make(map[string]map[string]struct{})
-loop:
-	for {
-		// get the rw core list from k8s
-		rwPods, err := getVolthaPods(clientset)
-		if err != nil {
-			log.Error(err)
-			continue
-		}
-
-		// for every pod
-		for _, pod := range rwPods {
-			// get the devices for this pod's backend
-			devices, have := deviceOwnership[pod.backend]
-			if !have {
-				devices = make(map[string]struct{})
-				deviceOwnership[pod.backend] = devices
-			}
-
-			coreDevices := queryPodDeviceIds(ctx, pod)
-
-			// handle devices that exist in the core, but we have just learned about
-			for deviceId := range coreDevices {
-				// if there's a new device
-				if _, have := devices[deviceId]; !have {
-					// add the device to our local list
-					devices[deviceId] = struct{}{}
-					// push the device into the affinity router
-					setAffinity(ctx, client, deviceId, pod.backend)
-				}
-			}
-
-			// ensure that the core knows about all devices in its backend
-			toSync := make(map[string]struct{})
-			for deviceId := range devices {
-				// if the pod is missing any devices
-				if _, have := coreDevices[deviceId]; !have {
-					// we will reconcile them
-					toSync[deviceId] = struct{}{}
-				}
-			}
-
-			if len(toSync) != 0 {
-				reconcilePodDeviceIds(ctx, pod, toSync)
-			}
-		}
-
-		select {
-		case <-ctx.Done():
-			// if we're done, exit
-			break loop
-		case <-time.After(10 * time.Second): // wait a while
-		}
-	}
-}
-
-// endOnClose cancels the context when the connection closes
-func connectionActiveContext(conn *grpc.ClientConn) context.Context {
-	ctx, disconnected := context.WithCancel(context.Background())
-	go func() {
-		for state := conn.GetState(); state != connectivity.TransientFailure && state != connectivity.Shutdown; state = conn.GetState() {
-			if !conn.WaitForStateChange(context.Background(), state) {
-				break
-			}
-		}
-		log.Infof("Connection to afrouter lost")
-		disconnected()
-	}()
-	return ctx
-}
-
-func main() {
+func startup() int {
 	config := &Configuration{}
 	cmdParse := flag.NewFlagSet(path.Base(os.Args[0]), flag.ContinueOnError)
 	config.DisplayVersionOnly = cmdParse.Bool("version", false, "Print version information and exit")
 
 	if err := cmdParse.Parse(os.Args[1:]); err != nil {
 		fmt.Printf("Error: %v\n", err)
-		os.Exit(1)
+		return 1
 	}
 
 	if *config.DisplayVersionOnly {
 		fmt.Println("VOLTHA API Server (afrouterd)")
 		fmt.Println(version.VersionInfo.String("  "))
-		return
+		return 0
 	}
 
 	// Set up logging
@@ -417,17 +60,17 @@
 	}
 
 	// Set up kubernetes api
-	clientset := k8sClientSet()
+	clientset := afrouterd.K8sClientSet()
 
 	for {
 		// Connect to the affinity router
-		conn, err := connect(context.Background(), afrouterApiAddress) // This is a sidecar container so communicating over localhost
+		conn, err := afrouterd.Connect(context.Background(), afrouterApiAddress) // This is a sidecar container so communicating over localhost
 		if err != nil {
 			panic(err)
 		}
 
 		// monitor the connection status, end context if connection is lost
-		ctx := connectionActiveContext(conn)
+		ctx := afrouterd.ConnectionActiveContext(conn)
 
 		// set up the client
 		client := pb.NewConfigurationClient(conn)
@@ -436,10 +79,10 @@
 		// these two processes do the majority of the work
 
 		log.Info("Starting discovery monitoring")
-		doneCh, _ := startDiscoveryMonitor(ctx, client)
+		doneCh, _ := afrouterd.StartDiscoveryMonitor(ctx, client)
 
 		log.Info("Starting core monitoring")
-		coreMonitor(ctx, client, clientset)
+		afrouterd.CoreMonitor(ctx, client, clientset)
 
 		//ensure the discovery monitor to quit
 		<-doneCh
@@ -447,3 +90,10 @@
 		conn.Close()
 	}
 }
+
+func main() {
+	status := startup()
+	if status != 0 {
+		os.Exit(status)
+	}
+}