From 254f4ca70f0cd6b95b4005f6e4378c1466635496 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ovidiu=20=C8=98tefan=20Popescu?=
 <stefanpopescu923@gmail.com>
Date: Thu, 15 Feb 2024 21:33:05 +0200
Subject: [PATCH] Created a more generic way to read configuration files

---
 backend/src/config/config.go      | 51 ++++++-----------------------
 backend/src/config/file_reader.go | 53 +++++++++++++++++++++++++++++++
 2 files changed, 62 insertions(+), 42 deletions(-)
 create mode 100644 backend/src/config/file_reader.go

diff --git a/backend/src/config/config.go b/backend/src/config/config.go
index 9b9cd64..0c21254 100644
--- a/backend/src/config/config.go
+++ b/backend/src/config/config.go
@@ -1,8 +1,6 @@
 package config
 
 import (
-	"errors"
-	"github.com/spf13/viper"
 	"log"
 	"os"
 	"time"
@@ -65,57 +63,26 @@ type CorsConfig struct {
 }
 
 func GetConfig() *Config {
-	cfgPath := getConfigPath(os.Getenv("APP_ENV"))
-	configReader, err := LoadConfig(cfgPath, "yml")
-	if err != nil {
-		log.Fatalf("Error while loading config: %v", err)
+	fileReader := FileReader[Config]{}
+	configFilePath := getConfigPath(os.Getenv("APP_ENV"))
+
+	config := fileReader.GetContent(configFilePath)
+	if config == nil {
+		return nil
 	}
 
-	config, err := ParseConfig(configReader)
-	envPort := os.Getenv("PORT")
-	if envPort != "" {
-		config.Server.ExternalPort = envPort
+	environmentPort := os.Getenv("PORT")
+	if environmentPort != "" {
+		config.Server.ExternalPort = environmentPort
 		log.Printf("Set external port from environment -> %s", config.Server.ExternalPort)
 	} else {
 		config.Server.ExternalPort = config.Server.InternalPort
 		log.Printf("Set external port from environment -> %s", config.Server.ExternalPort)
 	}
-	if err != nil {
-		log.Fatalf("Error while parsing config: %v", err)
-	}
 
 	return config
 }
 
-func ParseConfig(configReader *viper.Viper) (*Config, error) {
-	var config Config
-	err := configReader.Unmarshal(&config)
-	if err != nil {
-		log.Printf("Unable to parse config: %v", err)
-		return nil, err
-	}
-	return &config, nil
-}
-
-func LoadConfig(filename string, fileType string) (*viper.Viper, error) {
-	configReader := viper.New()
-	configReader.SetConfigType(fileType)
-	configReader.SetConfigName(filename)
-	configReader.AddConfigPath(".")
-	configReader.AutomaticEnv()
-
-	err := configReader.ReadInConfig()
-	if err != nil {
-		log.Printf("Unable to read config: %v", err)
-		var configFileNotFoundError viper.ConfigFileNotFoundError
-		if errors.As(err, &configFileNotFoundError) {
-			return nil, errors.New("could not find configuration file")
-		}
-		return nil, err
-	}
-	return configReader, nil
-}
-
 func getConfigPath(env string) string {
 	if env == "docker" {
 		return "/app/config/docker-config"
diff --git a/backend/src/config/file_reader.go b/backend/src/config/file_reader.go
new file mode 100644
index 0000000..4fc500a
--- /dev/null
+++ b/backend/src/config/file_reader.go
@@ -0,0 +1,53 @@
+package config
+
+import (
+	"errors"
+	"github.com/spf13/viper"
+	"log"
+)
+
+type FileReader[T any] struct {
+}
+
+func (reader *FileReader[T]) GetContent(filePath string) *T {
+	fileReader, err := reader.LoadFileContent(filePath, "yml")
+	if err != nil {
+		log.Fatalf("Error while loading file content: %v", err)
+	}
+
+	fileContent, err := reader.ParseFileContent(fileReader)
+	if err != nil {
+		log.Fatalf("Error while parsing file content: %v", err)
+	}
+
+	return fileContent
+}
+
+func (reader *FileReader[T]) ParseFileContent(fileReader *viper.Viper) (*T, error) {
+	var fileContent T
+	err := fileReader.Unmarshal(&fileContent)
+	if err != nil {
+		log.Printf("Unable to parse file: %v", err)
+		return nil, err
+	}
+	return &fileContent, nil
+}
+
+func (reader *FileReader[T]) LoadFileContent(fileName string, fileType string) (*viper.Viper, error) {
+	fileReader := viper.New()
+	fileReader.SetConfigType(fileType)
+	fileReader.SetConfigName(fileName)
+	fileReader.AddConfigPath(".")
+	fileReader.AutomaticEnv()
+
+	err := fileReader.ReadInConfig()
+	if err != nil {
+		log.Printf("Unable to read file content: %v", err)
+		var fileNotFoundError viper.ConfigFileNotFoundError
+		if errors.As(err, &fileNotFoundError) {
+			return nil, errors.New("could not find file")
+		}
+		return nil, err
+	}
+	return fileReader, nil
+}