Use uuid.UUID everywhere and have postgres generate ids

postgres/models.go

@@ -4,22 +4,33 @@ package postgres
 
 import (
 	"database/sql"
+	"time"
+
+	"github.com/google/uuid"
 )
 
 type Budget struct {
-	ID               string
 	Name             string
 	LastModification sql.NullTime
+	ID               uuid.UUID
+}
+
+type Transaction struct {
+	ID       uuid.UUID
+	BudgetID uuid.UUID
+	Date     time.Time
+	Memo     sql.NullString
+	Amount   string
 }
 
 type User struct {
-	ID       string
 	Email    string
 	Name     string
 	Password string
+	ID       uuid.UUID
 }
 
 type UserBudget struct {
-	UserID   string
-	BudgetID string
+	UserID   uuid.UUID
+	BudgetID uuid.UUID
 }