loc-serv.go

/*
 * Copyright (c) 2019  InterDigital Communications, Inc
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     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 server

import (
	"context"
	"encoding/json"
	"errors"
	"fmt"
	"net/http"
	"net/url"
	"os"
	"strconv"
	"strings"
	"time"

	sbi "github.com/InterDigitalInc/AdvantEDGE/go-apps/meep-loc-serv/sbi"
	dkm "github.com/InterDigitalInc/AdvantEDGE/go-packages/meep-data-key-mgr"
	httpLog "github.com/InterDigitalInc/AdvantEDGE/go-packages/meep-http-logger"
	clientNotifOMA "github.com/InterDigitalInc/AdvantEDGE/go-packages/meep-loc-serv-notification-client"
	log "github.com/InterDigitalInc/AdvantEDGE/go-packages/meep-logger"
	redis "github.com/InterDigitalInc/AdvantEDGE/go-packages/meep-redis"

	"github.com/gorilla/mux"
)

const LocServBasePath = "/location/v1/"
const locServKey string = "loc-serv:"

const typeZone = "zone"
const typeAccessPoint = "accessPoint"
const typeUser = "user"
const typeZonalSubscription = "zonalsubs"
const typeUserSubscription = "usersubs"
const typeZoneStatusSubscription = "zonestatus"

const USER_TRACKING_AND_ZONAL_TRAFFIC = 1
const ZONE_STATUS = 2

var nextZonalSubscriptionIdAvailable int
var nextUserSubscriptionIdAvailable int
var nextZoneStatusSubscriptionIdAvailable int

var zonalSubscriptionEnteringMap = map[int]string{}
var zonalSubscriptionLeavingMap = map[int]string{}
var zonalSubscriptionTransferringMap = map[int]string{}
var zonalSubscriptionMap = map[int]string{}

var userSubscriptionEnteringMap = map[int]string{}
var userSubscriptionLeavingMap = map[int]string{}
var userSubscriptionTransferringMap = map[int]string{}
var userSubscriptionMap = map[int]string{}

var zoneStatusSubscriptionMap = map[int]*ZoneStatusCheck{}

type ZoneStatusCheck struct {
	ZoneId                 string
	Serviceable            bool
	Unserviceable          bool
	Unknown                bool
	NbUsersInZoneThreshold int
	NbUsersInAPThreshold   int
}

var LOC_SERV_DB = 5

const redisAddr string = "meep-redis-master.default.svc.cluster.local:6379"

var rc *redis.Connector
var hostUrl *url.URL
var sandboxName string
var basePath string
var baseKey string

// Init - Location Service initialization
func Init() (err error) {

	// Retrieve Sandbox name from environment variable
	sandboxName = strings.TrimSpace(os.Getenv("MEEP_SANDBOX_NAME"))
	if sandboxName == "" {
		err = errors.New("MEEP_SANDBOX_NAME env variable not set")
		log.Error(err.Error())
		return err
	}
	log.Info("MEEP_SANDBOX_NAME: ", sandboxName)

	// Retrieve Host URL from environment variable
	hostUrl, err = url.Parse(strings.TrimSpace(os.Getenv("MEEP_HOST_URL")))
	if err != nil {
		hostUrl = new(url.URL)
	}
	log.Info("MEEP_HOST_URL: ", hostUrl)

	// Set base path
	basePath = "/" + sandboxName + LocServBasePath

	// Get base storage key
	baseKey = dkm.GetKeyRoot(sandboxName) + locServKey

	// Connect to Redis DB
	rc, err = redis.NewConnector(redisAddr, LOC_SERV_DB)
	if err != nil {
		log.Error("Failed connection to Redis DB. Error: ", err)
		return err
	}
	log.Info("Connected to Redis DB, location service table")

	userTrackingReInit()
	zonalTrafficReInit()
	zoneStatusReInit()

	//sbi is the sole responsible of updating the userInfo, zoneInfo and apInfo structures
	return sbi.Init(sandboxName, updateUserInfo, updateZoneInfo, updateAccessPointInfo, cleanUp)
}

// Run - Start Location Service
func Run() (err error) {
	return sbi.Run()
}

func createClient(notifyPath string) (*clientNotifOMA.APIClient, error) {
	// Create & store client for App REST API
	subsAppClientCfg := clientNotifOMA.NewConfiguration()
	subsAppClientCfg.BasePath = notifyPath
	subsAppClient := clientNotifOMA.NewAPIClient(subsAppClientCfg)
	if subsAppClient == nil {
		log.Error("Failed to create Subscription App REST API client: ", subsAppClientCfg.BasePath)
		err := errors.New("Failed to create Subscription App REST API client")
		return nil, err
	}
	return subsAppClient, nil
}

func deregisterZoneStatus(subsIdStr string) {
	subsId, _ := strconv.Atoi(subsIdStr)
	zonalSubscriptionMap[subsId] = ""
}

func registerZoneStatus(zoneId string, nbOfUsersZoneThreshold int32, nbOfUsersAPThreshold int32, opStatus []OperationStatus, subsIdStr string) {

	subsId, _ := strconv.Atoi(subsIdStr)

	var zoneStatus ZoneStatusCheck
	if opStatus != nil {
		for i := 0; i < len(opStatus); i++ {
			switch opStatus[i] {
			case SERVICEABLE:
				zoneStatus.Serviceable = true
			case UNSERVICEABLE:
				zoneStatus.Unserviceable = true
			case OPSTATUS_UNKNOWN:
				zoneStatus.Unknown = true
			default:
			}
		}
	}
	zoneStatus.NbUsersInZoneThreshold = (int)(nbOfUsersZoneThreshold)
	zoneStatus.NbUsersInAPThreshold = (int)(nbOfUsersAPThreshold)
	zoneStatus.ZoneId = zoneId

	zoneStatusSubscriptionMap[subsId] = &zoneStatus
}

func deregisterZonal(subsIdStr string) {
	subsId, _ := strconv.Atoi(subsIdStr)
	zonalSubscriptionMap[subsId] = ""
	zonalSubscriptionEnteringMap[subsId] = ""
	zonalSubscriptionLeavingMap[subsId] = ""
	zonalSubscriptionTransferringMap[subsId] = ""
}

func registerZonal(zoneId string, event []UserEventType, subsIdStr string) {

	subsId, _ := strconv.Atoi(subsIdStr)

	if event != nil {
		for i := 0; i < len(event); i++ {
			switch event[i] {
			case ENTERING:
				zonalSubscriptionEnteringMap[subsId] = zoneId
			case LEAVING:
				zonalSubscriptionLeavingMap[subsId] = zoneId
			case TRANSFERRING:
				zonalSubscriptionTransferringMap[subsId] = zoneId
			default:
			}