Handle config as struct with values from ENV file

config/config.go

@@ -0,0 +1,59 @@
+package config
+
+import (
+	"github.com/joho/godotenv"
+	"gitlab.com/saburly/kiviscraplib/structures"
+	"log"
+	"os"
+	"strconv"
+)
+
+var ClientConfig structures.ClientConfig
+var defaultValues = make(map[string]string)
+
+func InitConfig() {
+	err := godotenv.Load()
+	if err != nil {
+		log.Fatal("Unable to load ENV variables")
+	}
+
+	initDefaultValues()
+	generateClientConfigObject()
+}
+
+func generateClientConfigObject() {
+	ClientConfig.ConnectionsCount = getInt("CLIENT_CONNECTIONS_COUNT")
+	ClientConfig.ConnectionTimeout = getInt("CLIENT_CONNECTION_TIMEOUT")
+	ClientConfig.WorkerServerAddress = getString("WORKER_SERVER_ADDRESS")
+	ClientConfig.RequestMessagePrefix = getString("REQUEST_MESSAGE_PREFIX")
+	ClientConfig.ProxyListBaseURL = getString("PROXY_LIST_BASE_URL")
+}
+
+func initDefaultValues() {
+	defaultValues["CLIENT_CONNECTIONS_COUNT"] = "5"
+	defaultValues["CLIENT_CONNECTION_TIMEOUT"] = "2"
+	defaultValues["WORKER_SERVER_ADDRESS"] = "127.0.0.1:1338"
+	defaultValues["REQUEST_MESSAGE_PREFIX"] = "URL "
+	defaultValues["PROXY_LIST_BASE_URL"] = "https://www.proxy-list.download/api/v1/get?type="
+}
+
+func getInt(key string) int {
+	value := os.Getenv(key)
+	if len(value) == 0 {
+		value = defaultValues[key]
+	}
+
+	numericalValue, err := strconv.Atoi(value)
+	if err != nil {
+		log.Fatalf("Cannot convert ENV value for %s to the integer", key)
+	}
+	return numericalValue
+}
+
+func getString(key string) string {
+	value := os.Getenv(key)
+	if len(value) == 0 {
+		return defaultValues[key]
+	}
+	return value
+}

structures/structures.go

@@ -20,3 +20,11 @@ type ProxyServer struct {
 	Type    string
 	Address string
 }
+
+type ClientConfig struct {
+	ConnectionsCount     int
+	ConnectionTimeout    int // In seconds
+	WorkerServerAddress  string
+	RequestMessagePrefix string
+	ProxyListBaseURL     string
+}