regroup backend and frontend in app folder

app/backend/handlers/login_handler.go

@@ -0,0 +1,67 @@
+package handlers
+
+import (
+	"backend/models"
+	"crypto/rand"
+	"encoding/hex"
+	"log"
+	"net/http"
+
+	"github.com/gin-gonic/gin"
+)
+
+func (r *NodeHandler) LoginHandler(c *gin.Context) {
+	log.Println("trying to login")
+	r.Repo.LoginHandler(c)
+}
+
+func GenerateSecureKey() (string, error) {
+	bytes := make([]byte, 32) // 256 bits
+	if _, err := rand.Read(bytes); err != nil {
+		return "", err
+	}
+	return hex.EncodeToString(bytes), nil
+}
+
+func (r *NodeHandler) CreateApiKeyHandler(c *gin.Context) {
+
+	log.Println("trying to create key")
+	newApiKey, err := GenerateSecureKey()
+
+	if err != nil {
+		log.Printf("Generate API key error: %v", err)
+		c.JSON(http.StatusInternalServerError, gin.H{"error": "key creation error"})
+		return
+	}
+
+	var key models.CreateApiKeyResponse
+
+	key, err = r.Repo.CreateApiKeyHandler(c, newApiKey)
+
+	if err != nil {
+		log.Printf("CreateApiKeyHandler error: %v", err)
+		c.JSON(http.StatusInternalServerError, gin.H{"error": "insert new api key error"})
+		return
+	}
+
+	c.JSON(http.StatusOK, key)
+}
+
+func (h *NodeHandler) HandleRetrieveApiKeys(c *gin.Context) {
+
+	log.Println("All api keys retrieve request")
+
+	apiKeys := make([]models.ApiKey, 0)
+
+	apiKeys, err := h.Repo.RetriveApiKeyList()
+
+	if err != nil {
+		log.Printf("Request error on retrieving api keys: %v", err)
+		c.JSON(http.StatusInternalServerError, gin.H{"error": "error retrieving api keys"})
+		return
+	}
+
+	log.Printf("nb api keys: %v", len(apiKeys))
+
+	c.JSON(http.StatusOK, apiKeys)
+}