From d9d64cb067e044c9ae1d8320b93489c0224fedda Mon Sep 17 00:00:00 2001
From: Eduardo Silva <eduardosilva@disroot.org>
Date: Sun, 21 Sep 2025 14:30:33 +0100
Subject: [PATCH] Added configuration

---
 api/api.go            |  4 +++-
 api/authMiddleware.go |  7 +++---
 config.yaml           |  5 ++++
 config/config.go      | 56 +++++++++++++++++++++++++++++++++++++++++++
 main.go               |  2 ++
 5 files changed, 70 insertions(+), 4 deletions(-)
 create mode 100644 config.yaml
 create mode 100644 config/config.go

diff --git a/api/api.go b/api/api.go
index 88b7375..e2fa361 100644
--- a/api/api.go
+++ b/api/api.go
@@ -5,6 +5,7 @@ import (
 	"net/http"
 	"strconv"
 
+	"github.com/ESilva15/PTInvCertSWDB/config"
 	sw "github.com/ESilva15/PTInvCertSWDB/sw"
 
 	"github.com/gin-gonic/gin"
@@ -48,6 +49,7 @@ func count(c *gin.Context) {
 }
 
 func RunServer() error {
+	cfg := config.GetInstance()
 	gin.SetMode(ginMode)
 	router := gin.Default()
 
@@ -64,7 +66,7 @@ func RunServer() error {
 		return err
 	}
 
-	err = router.Run(":8086")
+	err = router.Run(":" + cfg.Port)
 	if err != nil {
 		return err
 	}
diff --git a/api/authMiddleware.go b/api/authMiddleware.go
index 9602010..c783f14 100644
--- a/api/authMiddleware.go
+++ b/api/authMiddleware.go
@@ -4,6 +4,7 @@ import (
 	"net/http"
 	"strings"
 
+	"github.com/ESilva15/PTInvCertSWDB/config"
 	"github.com/gin-gonic/gin"
 	"github.com/golang-jwt/jwt/v4"
 )
@@ -12,11 +13,11 @@ type TokenData struct {
 	Token string `json:"JWTToken"`
 }
 
-const key = "stronk"
-
 func validateToken(tStr string) (bool, error) {
+	cfg := config.GetInstance()
+
 	token, err := jwt.Parse(tStr, func(token *jwt.Token) (any, error) {
-		return []byte(key), nil
+		return []byte(cfg.AuthKey), nil
 	}, jwt.WithValidMethods([]string{jwt.SigningMethodHS256.Alg()}))
 	if err != nil {
 		return false, err
diff --git a/config.yaml b/config.yaml
new file mode 100644
index 0000000..109a74b
--- /dev/null
+++ b/config.yaml
@@ -0,0 +1,5 @@
+port: 8086
+authKey: "stronk"
+dataBackend: "YAML"
+yamlBackend:
+  path: "./swdb.yaml"
diff --git a/config/config.go b/config/config.go
new file mode 100644
index 0000000..62daf62
--- /dev/null
+++ b/config/config.go
@@ -0,0 +1,56 @@
+// Package config defines the configuration of our app
+package config
+
+import (
+	"log"
+	"os"
+	"sync"
+
+	"gopkg.in/yaml.v2"
+)
+
+type YamlBackend struct {
+	Path string `yaml:"path"`
+}
+
+// Configuration defines the base configuration of the expenses app
+type Configuration struct {
+	Port        string      `yaml:"port"`
+	AuthKey     string      `yaml:"authKey"`
+	DataBackend string      `yaml:"dataBackend"`
+	YamlBackend YamlBackend `yaml:"yamlBackend"`
+}
+
+var (
+	instance *Configuration
+	once     sync.Once
+	confPath string
+)
+
+// GetInstance returns the instance of the configuration of the app.
+func GetInstance() *Configuration {
+	once.Do(func() {
+		instance = &Configuration{}
+		instance.loadConfiguration()
+	})
+
+	return instance
+}
+
+// SetConfig sets the path for the configuration file.
+func SetConfig(path string) {
+	confPath = path
+}
+
+func (c *Configuration) loadConfiguration() {
+	file, err := os.ReadFile(confPath)
+	if err != nil {
+		log.Fatalf("Unable to open configuration file [%s]: %s", confPath,
+			err.Error())
+	}
+
+	err = yaml.Unmarshal(file, &instance)
+	if err != nil {
+		log.Fatalf("Error parsing JSON: %s", err.Error())
+	}
+}
diff --git a/main.go b/main.go
index aa17f5f..faa6cea 100644
--- a/main.go
+++ b/main.go
@@ -2,8 +2,10 @@ package main
 
 import (
 	cmd "github.com/ESilva15/PTInvCertSWDB/cmd"
+	"github.com/ESilva15/PTInvCertSWDB/config"
 )
 
 func main() {
+	config.SetConfig("./config.yaml")
 	cmd.Execute()
 }