DMAC/internal/pkg/server/reactormanager.go

package server

import (
    "fmt"
    "time"
    _ "log"
    "context"
    "sync"
    "FRMS/internal/pkg/logging"
    "google.golang.org/grpc"
    "google.golang.org/grpc/status"
    "google.golang.org/grpc/credentials/insecure"
    pb "FRMS/internal/pkg/grpc"
)

// this package will implement a reactor coordinator and associated go routines

type ReactorManager struct {
    *Manager
    StatusMon *StatusMonitor
    *devstatus
}

type devstatus struct {
    sync.Mutex
    Devs map[uint32]*DeviceInfo
}

func NewReactorManager(c *Client,sys *SystemViewer,err chan error) GeneralManager {
    r := &ReactorManager{}
    di := make(map[uint32]*DeviceInfo)
    r.devstatus = &devstatus{Devs:di}
    r.Manager = NewManager(err)
    r.StatusMon = NewStatusMonitor("Reactor",c.Id,sys)
    return r
}

func (r *ReactorManager) Start(cl *Client) {
    r.Manager.Start(cl)
    logging.Debug(logging.DStart,"RMA %v starting", r.Id)
    go r.StatusMon.Send(&DeviceInfo{Id:r.Id,Type:"Reactor",Status:"[green]ONLINE[white]"},"Reactor")
    conn := r.Connect()
    empty := &grpc.ClientConn{}
    if conn != empty {
        go r.Monitor(conn)
    }
}

func (r *ReactorManager) Exit() {
    r.Manager.Exit()
    logging.Debug(logging.DExit, "RMA %v exiting", r.Id)
    go r.StatusMon.Send(&DeviceInfo{Id:r.Id,Type:"Reactor",Status:"[red]OFFLINE[white]",Data:fmt.Sprintf("Last Seen %v",time.Now().Format("Mon at 03:04:05pm MST"))},"Reactor")
}

func (r *ReactorManager) GetPort() int {
    return 0
}

func (r *ReactorManager) Connect() *grpc.ClientConn {
    // establish gRPC conection with reactor
    var opts []grpc.DialOption
    var conn *grpc.ClientConn
    opts = append(opts,grpc.WithTransportCredentials(insecure.NewCredentials()))

    for {
        if !r.IsActive() {
            logging.Debug(logging.DClient,"RMA %v No longer active, aborting connection attempt",r.Id)
            return &grpc.ClientConn{}
        }
        var err error
        conn, err = grpc.Dial(fmt.Sprintf("%v:%v",r.Ip,r.Port),opts...)
        // error handling
        code := status.Code(err)
        if code != 0 { // != OK
            if code == (5 | 14) { // unavailable or not found
                to := r.Timeout()
                if to == 0 {
                    logging.Debug(logging.DClient,"RMA %v Client not responding",r.Id)
                    return &grpc.ClientConn{}
                }
                logging.Debug(logging.DClient,"RMA %v Client currently down, retrying in %v ms",r.Id, to)
                time.Sleep(time.Duration(to) * time.Millisecond)

            } else {
                logging.Debug(logging.DError,"RMA %v GRPC ERROR: %v",r.Id, code)
                r.Err <- err
            }
        }
        break;
    }
    return conn
}

func (r *ReactorManager) Monitor(conn *grpc.ClientConn) {
    defer conn.Close()
    client := pb.NewMonitoringClient(conn)
    for r.IsActive() {
        req := &pb.ReactorStatusRequest{Id:r.Id}
        resp, err := client.GetReactorStatus(context.Background(),req)
        code := status.Code(err)
        if code != 0 { // if != OK
            logging.Debug(logging.DClient,"RMA %v Reactor not responding! Code: %v\n", r.Id,code)
            r.devstatus.Lock()
            for _, d := range r.Devs {
                newd := d
                newd.Status = "[yellow]UNKOWN[white]"
                r.Devs[newd.Id] = newd
                go r.StatusMon.Send(newd,"Device")
            }
            r.devstatus.Unlock()
            r.Exit()
            break;
        }
        for _,v := range resp.GetDevices() {
            d := &DeviceInfo{Id:uint32(v.GetAddr()),Type:v.GetType(),Status:v.GetStatus(),Data:v.GetData()}
            go r.UpdateDevice(d)
        }
        time.Sleep(r.Hb) // time between sensor pings
    }
}

func (r *ReactorManager) UpdateDevice(d *DeviceInfo) {
    r.devstatus.Lock()
    defer r.devstatus.Unlock()
    if olddev, ok := r.Devs[d.Id]; !ok {
        // new device
        r.Devs[d.Id] = d
        go r.StatusMon.Send(d,"Device")
    } else if olddev.Status != d.Status || olddev.Data != d.Data {
            // dev status or data has changed
        r.Devs[d.Id] = d
        go r.StatusMon.Send(d,"Device")
    }
}