Single connection to external services

src/app/plugins.go

@@ -3,6 +3,7 @@ package app
 import (
 	"context"
 	"log"
+	"sync/atomic"
 	"time"
 
 	redis "github.com/go-redis/redis/v8"
@@ -41,70 +42,84 @@ func (pm *PluginManager) GetDatabase() *pgxpool.Pool {
 }
 
 func CachePlugin(cnf *Config, w WorkerInterface) Plugin {
+	var redisConn atomic.Value
+
 	connectFn := func(w WorkerInterface) *redis.Client {
 		log.Println("establishing api-cache connection...")
 
-		return redis.NewClient(&redis.Options{
+		conn := redis.NewClient(&redis.Options{
 			Addr:        cnf.CacheAddr,
 			Username:    cnf.CacheUsername,
 			Password:    cnf.CachePassword,
 			DB:          0,                      // TODO
 			DialTimeout: 100 * time.Millisecond, // TODO
 		})
+		redisConn.Store(conn)
+
+		return conn
 	}
 
+	connectFn(w)
+
 	// checking if the connection is still alive and try to reconnect when it is not
-	go func(conn *redis.Client) {
+	go func() {
 		tick := time.NewTicker(5 * time.Second) // is 5 seconds is not too much?
 		defer tick.Stop()
 
 		for range tick.C {
+			conn := redisConn.Load().(*redis.Client)
 			if err := conn.Ping(context.Background()).Err(); err != nil {
 				log.Println("lost connection with api-cache. Reconnecting...")
-				conn = connectFn(w)
+				connectFn(w)
 			}
 		}
-	}(connectFn(w))
+	}()
 
 	return Plugin{
 		name: "cache",
 		connect: func(w *WorkerInterface) any {
-			return connectFn(*w)
+			return redisConn.Load().(*redis.Client)
 		},
 	}
 }
 
 func DatabasePlugin(cnf *Config, w WorkerInterface) Plugin {
+	var dbConn atomic.Value
+
 	connectFn := func(w WorkerInterface) *pgxpool.Pool {
 		log.Println("establishing db-postgres connection...")
 
 		conn, err := pgxpool.New(context.Background(), cnf.DbURL)
 		if err != nil {
 			log.Printf("failed to connect to the database: %s. Err: %s\n", cnf.DbURL, err.Error())
+
 			return nil
-			// os.Exit(1)
 		}
+		dbConn.Store(conn)
 
 		return conn
 	}
 
+	connectFn(w)
+
 	// checking if the connection is still alive and try to reconnect when it is not
-	go func(conn *pgxpool.Pool) {
+	go func() {
 		tick := time.NewTicker(5 * time.Second) // is 5 seconds is not too much?
 		defer tick.Stop()
 
 		for range tick.C {
+			conn := dbConn.Load().(*pgxpool.Pool)
 			if err := conn.Ping(context.Background()); err != nil {
 				log.Println("lost connection with db-postgres. Reconnecting...")
-				conn = connectFn(w)
+				connectFn(w)
 			}
 		}
-	}(connectFn(w))
+	}()
 
 	return Plugin{
 		name: "database",
 		connect: func(w *WorkerInterface) any {
-			return connectFn(*w)
+			return dbConn.Load().(*pgxpool.Pool)
 		},
 	}
 }