Global var struct updates not available in other testing functions

Question

I'm testing an API where I need to "login" and get an Auth Token that I store in a struct and pass to my functions. I'm trying to write a '_test.go' file, but the Auth Token is not getting passed to the testing functions, and I'm not sure why. All the online example test files are very simplistic, and I can't find any example that's even close to what I am trying to do here -- but then again, it could be my Google Foo is weak today..

Here's the code:

package myapi

import (
    "flag"
    "fmt"
    "os"
    "testing"
)

// The Global var that needs to be read/write-able from all the testing func's
var d Device

func TestMain(m *testing.M) {
    // --- Log into our test device ---
    d.Address = os.Getenv("THEIP")
    d.Username = "admin"
    d.Password = "password"
    d, err := d.Login()
    if err != nil {
        panic(err)
    }
    if d.Token == "" {
        panic("Auth Token Missing")
    }

    // --- Run the Tests ---
    flag.Parse()
    ex := m.Run()

    // --- Log off the test device ---
    d, err = d.Logoff()
    if err != nil {
        panic(err)
    }

    // --- End the Tests ---
    os.Exit(ex)
}

func TestGetUpdate(t *testing.T) {
    f, err := d.GetUpdate()
    if err != nil {
        t.Error(err)
    }
    fmt.Println(f)
}

The 'd' struct holds all the info I need to do the API call, and I was thinking that declaring it as a global, it would be available to all the test func's, but I always get "Auth Token Missing" errors when I call my API functions:

$ export THEIP="10.1.1.3"; go test -v
=== RUN   TestGetUpdate

--- FAIL: TestGetUpdate (0.00s)
    api_system_test.go:46: No Auth Token! You must Login() before calling other API calls
FAIL
exit status 1
FAIL    a10/axapi       0.015s

The test for the Auth Token passes in the TestMain(), but the updates to the struct don't seem to be coming out. I can't pass the struct as a var or a reference, as that breaks the testing. What am I doing wrong?

Answer 1

Once you start the testGetUpdate those values that you are looking for, as stated in TestMain, are not there for passing this test and the function call that it performs in the test. You would be better mocking the struct, placing a constant, or performing another setup for these values in another function that can be called and set those variables. The Constant may be the easiest especially if you are going to use this in other tests. Otherwise you are going to have to place the information in every test in order to pass the values of the structs.

Another option is to pass a t.run() inside of a main testing function that way the application knows what values you are wanting to run inside your tests.