interface conversion: interface {} is nil, not map[string]interface {} [recovered] - unit-testing

Question

I try to make unit test for success create user. But, I got a problem to do it, I always fail to make it and always get error 500 or Internal Server Error. Actually, the handler function to create user is work when I run main.go, but the function unit test is doesn't wotk. Here is the code.
package test
func setupDB() *sql.DB {
var (
username = "root"
password = "root"
host = "localhost"
port = "3306"
db_name = "go-fiber-test"
)
dns := fmt.Sprintf("%s:%s#tcp(%s:%s)/%s?parseTime=True", username, password, host, port, db_name)
db, err := sql.Open("mysql", dns)
if err != nil {
panic(err)
}
db.SetMaxIdleConns(10)
db.SetMaxOpenConns(100)
db.SetConnMaxIdleTime(5 * time.Minute)
db.SetConnMaxLifetime(60 * time.Minute)
return db
}
func setupRouter(db *sql.DB) *fiber.App{
validator := validator.New()
userRepository := repository.NewUserRepository()
userService := service.NewUserService(userRepository, db, validator)
userController := controller.NewUserController(userService)
router := route.RouteInit(userController)
return router
}
func truncateUsers(db *sql.DB) {
db.Exec("TRUNCATE users")
}
func TestCreateUsersSuccess(t *testing.T) {
db := setupDB()
router := setupRouter(db)
requestBody := strings.NewReader(`
{
"name": "myname",
"email": "mynamecool329#gmail.com",
"password": "myname!##",
"address": "Jl. nanananaaana",
"phone": "0812388773342"
}
`)
request := httptest.NewRequest("POST", "http://localhost:3000/users/create", requestBody)
response, err := router.Test(request)
helper.PanicIfError(err)
assert.Equal(t, 200, response.StatusCode)
body, err := io.ReadAll(response.Body)
helper.PanicIfError(err)
var responseBody map[string]interface{}
err = json.Unmarshal(body, &responseBody)
helper.PanicIfError(err)
log.Printf("request : %v", request)
log.Printf("response : %v", response)
log.Printf("response body : %v", response.Body)
log.Printf("response body Map: %v", responseBody)
assert.Equal(t, 200, int(responseBody["code"].(float64)))
assert.Equal(t, "SUCCESS", responseBody["status"])
assert.Equal(t, "myname", responseBody["data"].(map[string]interface{})["name"])
}
package route
func RouteInit(userController controller.UserController) *fiber.App {
app := fiber.New()
app.Use(func(c *fiber.Ctx) error {
defer func() {
if err := recover(); err != nil {
exception.ErrorHandler(c, err)
}
}()
return c.Next()
})
app.Get("/users", middleware.AuthMiddleware, userController.FindAll)
app.Get("/users/:userId", userController.FindById)
app.Put("/users/:userId", middleware.AuthMiddleware, userController.Update)
app.Delete("/users/:userId", middleware.AuthMiddleware, userController.Delete)
app.Post("/users/create", userController.Create)
app.Post("/login", userController.Login)
app.Get("/logout", middleware.AuthMiddleware, userController.Logout)
app.Post("/verify", userController.Verify)
return app
}
The output
=== RUN TestCreateUsersSuccess
2023/02/16 11:22:00 request : &{POST http://localhost:3000/users/create HTTP/1.1 1 1 map[Content-Length:[163]] {
{
"name": "myname",
"email": "mynamecool329#gmail.com",
"password": "myname!##",
"address": "Jl. nanananaaana",
"phone": "0812388773342"
}
} <nil> 163 [] false localhost:3000 map[] map[] <nil> map[] 192.0.2.1:1234 http://localhost:3000/users/create <nil> <nil> <nil> <nil>}
2023/02/16 11:22:00 response : &{200 OK 200 HTTP/1.1 1 1 map[Content-Length:[57] Content-Type:[application/json] Date:[Thu, 16 Feb 2023 04:22:00 GMT]] 0xc00037b940 57 [] false false map[] 0xc000113d00 <nil>}
2023/02/16 11:22:00 response body : &{0xc00000edb0 <nil> <nil> false false {0 0} true false false <nil>}
2023/02/16 11:22:00 response body Map: map[code:500 data:<nil> status:INTERNAL SERVER ERROR]
/home/myname/Documents/Go/go-fiber/unit-test/user/create_test.go:99:
Error Trace: /home/myname/Documents/Go/go-fiber/unit-test/user/create_test.go:99
Error: Not equal:
expected: 200
actual : 500
Test: TestCreateUsersSuccess
/home/myname/Documents/Go/go-fiber/unit-test/user/create_test.go:100:
Error Trace: /home/myname/Documents/Go/go-fiber/unit-test/user/create_test.go:100
Error: Not equal:
expected: "SUCCESS"
actual : "INTERNAL SERVER ERROR"
Diff:
--- Expected
+++ Actual
## -1 +1 ##
-SUCCESS
+INTERNAL SERVER ERROR
Test: TestCreateUsersSuccess
--- FAIL: TestCreateUsersSuccess (0.00s)
panic: interface conversion: interface {} is nil, not map[string]interface {} [recovered]
panic: interface conversion: interface {} is nil, not map[string]interface {}
goroutine 6 [running]:
testing.tRunner.func1.2({0x7e5700, 0xc0003c13b0})
/usr/lib/go-1.18/src/testing/testing.go:1389 +0x24e
testing.tRunner.func1()
/usr/lib/go-1.18/src/testing/testing.go:1392 +0x39f
panic({0x7e5700, 0xc0003c13b0})
/usr/lib/go-1.18/src/runtime/panic.go:838 +0x207
go_fiber/unit-test/user.TestCreateUsersSuccess(0x0?)
/home/myname/Documents/Go/go-fiber/unit-test/user/create_test.go:101 +0x425
testing.tRunner(0xc00037c9c0, 0x87f6b8)
/usr/lib/go-1.18/src/testing/testing.go:1439 +0x102
created by testing.(*T).Run
/usr/lib/go-1.18/src/testing/testing.go:1486 +0x35f
FAIL go_fiber/unit-test/user 0.027s
How to fix that problem?