NOISSUE - Store successfull OPC-UA subscriptions (#999)

Signed-off-by: Manuel Imperiale <manuel.imperiale@gmail.com>

cmd/opcua/main.go

@@ -5,9 +5,7 @@ package main
 
 import (
 	"context"
-	"encoding/csv"
 	"fmt"
-	"io"
 	"log"
 	"net/http"
 	"os"
@@ -20,6 +18,7 @@ import (
 	"github.com/mainflux/mainflux/logger"
 	"github.com/mainflux/mainflux/opcua"
 	"github.com/mainflux/mainflux/opcua/api"
+	"github.com/mainflux/mainflux/opcua/db"
 	"github.com/mainflux/mainflux/opcua/gopcua"
 	pub "github.com/mainflux/mainflux/opcua/nats"
 	"github.com/mainflux/mainflux/opcua/redis"
@@ -44,7 +43,6 @@ const (
 	defRouteMapURL    = "localhost:6379"
 	defRouteMapPass   = ""
 	defRouteMapDB     = "0"
-	defNodesConfig    = "/config/nodes.csv"
 
 	envHTTPPort       = "MF_OPCUA_ADAPTER_HTTP_PORT"
 	envLogLevel       = "MF_OPCUA_ADAPTER_LOG_LEVEL"
@@ -60,13 +58,10 @@ const (
 	envRouteMapURL    = "MF_OPCUA_ADAPTER_ROUTE_MAP_URL"
 	envRouteMapPass   = "MF_OPCUA_ADAPTER_ROUTE_MAP_PASS"
 	envRouteMapDB     = "MF_OPCUA_ADAPTER_ROUTE_MAP_DB"
-	envNodesConfig    = "MF_OPCUA_ADAPTER_CONFIG_FILE"
 
 	thingsRMPrefix     = "thing"
 	channelsRMPrefix   = "channel"
 	connectionRMPrefix = "connection"
-
-	columns = 2
 )
 
 type config struct {
@@ -81,7 +76,6 @@ type config struct {
 	routeMapURL    string
 	routeMapPass   string
 	routeMapDB     string
-	nodesConfig    string
 }
 
 func main() {
@@ -129,7 +123,7 @@ func main() {
 		}, []string{"method"}),
 	)
 
-	go subscribeToNodesFromFile(sub, cfg.nodesConfig, cfg.opcuaConfig, logger)
+	go subscribeToStoredSubs(sub, cfg.opcuaConfig, logger)
 	go subscribeToThingsES(svc, esConn, cfg.esConsumerName, logger)
 
 	errs := make(chan error, 2)
@@ -165,7 +159,6 @@ func loadConfig() config {
 		routeMapURL:    mainflux.Env(envRouteMapURL, defRouteMapURL),
 		routeMapPass:   mainflux.Env(envRouteMapPass, defRouteMapPass),
 		routeMapDB:     mainflux.Env(envRouteMapDB, defRouteMapDB),
-		nodesConfig:    mainflux.Env(envNodesConfig, defNodesConfig),
 	}
 }
 
@@ -194,45 +187,22 @@ func connectToRedis(redisURL, redisPass, redisDB string, logger logger.Logger) *
 	})
 }
 
-func subscribeToNodesFromFile(sub opcua.Subscriber, nodes string, cfg opcua.Config, logger logger.Logger) {
+func subscribeToStoredSubs(sub opcua.Subscriber, cfg opcua.Config, logger logger.Logger) {
-	if _, err := os.Stat(nodes); os.IsNotExist(err) {
+	// Get all stored subscriptions
-		logger.Warn(fmt.Sprintf("Config file not found: %s", err))
+	nodes, err := db.ReadAll()
-		return
-	}
-
-	file, err := os.OpenFile(nodes, os.O_RDONLY, os.ModePerm)
 	if err != nil {
-		logger.Warn(fmt.Sprintf("Failed to open config file: %s", err))
+		logger.Warn(fmt.Sprintf("Read stored subscriptions failed: %s", err))
-		return
-	}
-	defer file.Close()
-
-	reader := csv.NewReader(file)
-	for {
-		l, err := reader.Read()
-		if err == io.EOF {
-			break
-		}
-		if err != nil {
-			logger.Warn(fmt.Sprintf("Failed to read config file: %s", err))
-			return
 	}
 
-		if len(l) < columns {
+	for _, n := range nodes {
-			logger.Warn("Empty or incomplete line found in file")
+		cfg.ServerURI = n.ServerURI
-			return
+		cfg.NodeID = n.NodeID
-		}
+		go func() {
-
-		cfg.ServerURI = l[0]
-		cfg.NodeID = l[1]
-		go subscribe(sub, cfg, logger)
-	}
-}
-
-func subscribe(sub opcua.Subscriber, cfg opcua.Config, logger logger.Logger) {
 			if err := sub.Subscribe(cfg); err != nil {
 				logger.Warn(fmt.Sprintf("Subscription failed: %s", err))
 			}
+		}()
+	}
 }
 
 func subscribeToOpcuaServer(gc opcua.Subscriber, cfg opcua.Config, logger logger.Logger) {

docker/addons/opcua-adapter/docker-compose.yml

@@ -12,6 +12,9 @@ networks:
   docker_mainflux-base-net:
     external: true
 
+volumes:
+  mainflux-opcua-adapter-volume:
+
 services:
   opcua-redis:
     image: redis:5.0-alpine
@@ -47,4 +50,4 @@ services:
     networks:
       - docker_mainflux-base-net
     volumes:
-      - ./nodes.csv:/config/nodes.csv
+      - mainflux-opcua-adapter-volume:/store

docker/addons/opcua-adapter/nodes.csv

@@ -1 +0,0 @@
-opc.tcp://opcua.rocks:4840,ns=0;i=2256

opcua/db/subs.go

@@ -0,0 +1,75 @@
+// Copyright (c) Mainflux
+// SPDX-License-Identifier: Apache-2.0
+
+package db
+
+import (
+	"encoding/csv"
+	"io"
+	"os"
+
+	"github.com/mainflux/mainflux/errors"
+)
+
+const columns = 2
+const path = "/store/nodes.csv"
+
+var (
+	errNotFound  = errors.New("file not found")
+	errWriteFile = errors.New("failed de write file")
+	errOpenFile  = errors.New("failed to open file")
+	errReadFile  = errors.New("failed to read file")
+	errEmptyLine = errors.New("empty or incomplete line found in file")
+)
+
+// Node represents an OPC-UA node
+type Node struct {
+	ServerURI string
+	NodeID    string
+}
+
+// Save stores a successfull subscription
+func Save(serverURI, nodeID string) error {
+	file, err := os.OpenFile(path, os.O_CREATE|os.O_WRONLY, os.ModePerm)
+	if err != nil {
+		errors.Wrap(errWriteFile, err)
+	}
+	csvWriter := csv.NewWriter(file)
+	csvWriter.Write([]string{serverURI, nodeID})
+	csvWriter.Flush()
+
+	return nil
+}
+
+// ReadAll returns all stored subscriptions
+func ReadAll() ([]Node, error) {
+	if _, err := os.Stat(path); os.IsNotExist(err) {
+		return nil, errors.Wrap(errNotFound, err)
+	}
+
+	file, err := os.OpenFile(path, os.O_RDONLY, os.ModePerm)
+	if err != nil {
+		return nil, errors.Wrap(errOpenFile, err)
+	}
+	defer file.Close()
+
+	reader := csv.NewReader(file)
+	nodes := []Node{}
+	for {
+		l, err := reader.Read()
+		if err == io.EOF {
+			break
+		}
+		if err != nil {
+			return nil, errors.Wrap(errReadFile, err)
+		}
+
+		if len(l) < columns {
+			return nil, errEmptyLine
+		}
+
+		nodes = append(nodes, Node{l[0], l[1]})
+	}
+
+	return nodes, nil
+}

opcua/gopcua/subscribe.go

@@ -14,6 +14,7 @@ import (
 	"github.com/mainflux/mainflux/errors"
 	"github.com/mainflux/mainflux/logger"
 	"github.com/mainflux/mainflux/opcua"
+	"github.com/mainflux/mainflux/opcua/db"
 )
 
 const protocol = "opcua"
@@ -124,7 +125,13 @@ func (c client) runHandler(sub *opcuaGopcua.Subscription, cfg opcua.Config) erro
 
 	go sub.Run(c.ctx)
 
-	c.logger.Info(fmt.Sprintf("subscribe to server %s and node_id %s", cfg.ServerURI, cfg.NodeID))
+	// Store subscription details
+	if err := db.Save(cfg.ServerURI, cfg.NodeID); err != nil {
+		return err
+	}
+
+	c.logger.Info(fmt.Sprintf("subscribed to server %s and node_id %s", cfg.ServerURI, cfg.NodeID))
+
 	for {
 		select {
 		case <-c.ctx.Done():

opcua/service.go

@@ -120,7 +120,12 @@ func (as *adapterService) ConnectThing(mfxChanID, mfxThingID string) error {
 
 	as.cfg.NodeID = nodeID
 	as.cfg.ServerURI = serverURI
-	go as.subscribe(as.cfg)
+
+	go func() {
+		if err := as.subscriber.Subscribe(as.cfg); err != nil {
+			as.logger.Warn(fmt.Sprintf("subscription failed: %s", err))
+		}
+	}()
 
 	c := fmt.Sprintf("%s:%s", mfxChanID, mfxThingID)
 	return as.connectRM.Save(c, c)
@@ -138,9 +143,3 @@ func (as *adapterService) DisconnectThing(mfxChanID, mfxThingID string) error {
 	c := fmt.Sprintf("%s:%s", mfxChanID, mfxThingID)
 	return as.connectRM.Remove(c)
 }
-
-func (as *adapterService) subscribe(cfg Config) {
-	if err := as.subscriber.Subscribe(cfg); err != nil {
-		as.logger.Warn(fmt.Sprintf("subscription failed: %s", err))
-	}
-}