Implement NewBudget in BudgetService

budget.go

@@ -21,4 +21,5 @@ type UserBudget struct {
 type BudgetService interface {
 	Budget(id string) (*Budget, error)
 	BudgetsForUser(id string) ([]*Budget, error)
+	NewBudget(name string, userID string) (*Budget, error)
 }

postgres/budgetservice.go

@@ -25,3 +25,19 @@ func (s *Repository) BudgetsForUser(id string) ([]*budgeteer.Budget, error) {
 	return user.Budgets, nil
 
 }
+
+func (s *Repository) NewBudget(name string, userID string) (*budgeteer.Budget, error) {
+	b := &budgeteer.Budget{ID: s.IDGenerator.New(), Name: name}
+	err := s.DB.Insert(b)
+	if err != nil {
+		return nil, err
+	}
+
+	ub := &budgeteer.UserBudget{UserID: userID, BudgetID: b.ID}
+	err = s.DB.Insert(ub)
+	if err != nil {
+		return nil, err
+	}
+
+	return b, nil
+}