Testing passwordless auth in Firebase test lab for iOS - ios

Question

I am trying to figure out how to perform e2e test via firebase test lab for iOS that allow to check passwordless authentication flow, which essentially should do following
Enters email within my app
Firebase sends auth link to such email
Somehow I need to be logged into such email somewhere in firebases test device, I assume either in mail app, or gmail?
I need to know when new email arrives and open it
Once I opened an email I need to click on auth link
This should bring me back into the app and authenticate
My biggest issue at the moment is figuring out steps that happen outside my app i.e. how can I prepare for this test and log in under my email address (is it better to log into gmail in safari for example or somehow add this acc to apples mail app?).

Answer 1

Testing email
In my experience, testing your own code to see if an email was sent is not straightforward beyond checking if the method call you expect to send the email has happened.
Add on top of that using Firebase, which does not expose its underlying email send code, and that looks like a challenge to me.
In terms of testing, I suggest you assert that your method calls to send email happened or that the relevant code path was reached. In Firebase web, this looks like:
firebase.auth().sendSignInLinkToEmail(email, actionCodeSettings)
.then(function() {
// The link was successfully sent. Inform the user.
// Save the email locally so you don't need to ask the user for it again
// if they open the link on the same device.
window.localStorage.setItem('emailForSignIn', email);
// TODO save email to something accessible in your iOS tests
// TODO In your tests, confirm that email was saved after it was sent
})
.catch(function(error) {
// Some error occurred, you can inspect the code: error.code
});
See: https://firebase.google.com/docs/auth/web/email-link-auth#send_an_authentication_link_to_the_users_email_address
Another option:
You could setup a test user with an email address on a mail server that you manage, and check for incoming mail for that test user with your own custom mail reading code.
I would use Firebase Admin tools for this: https://firebase.google.com/docs/auth/admin/manage-users#create_a_user

Answer 2

I think you should first take a look at firebase docs for iOS on how to create dynamic links that you can use for email auth.
https://firebase.google.com/docs/auth/ios/email-link-auth
https://firebase.google.com/docs/auth/ios/passing-state-in-email-actions#configuring_firebase_dynamic_links
After you're done with those two check out the following code:
func application(_ application: UIApplication, open url: URL, sourceApplication: String?, annotation: Any) -> Bool {
// [END old_delegate]
if handlePasswordlessSignIn(withURL: url) {
return true
}
}
func handlePasswordlessSignIn(withURL url: URL) -> Bool {
let link = url.absoluteString
// [START is_signin_link]
if Auth.auth().isSignIn(withEmailLink: link) {
// [END is_signin_link]
UserDefaults.standard.set(link, forKey: "Link")
(window?.rootViewController as? UINavigationController)?.popToRootViewController(animated: false)
window?.rootViewController?.children[0].performSegue(withIdentifier: "passwordless", sender: nil)
return true
}
return false
}
This is just an example on how you can handle the deep link in your app after the user taps the link. The delegate method
func application(_ application: UIApplication, open url: URL,
sourceApplication: String?, annotation: Any) -> Bool
in AppDelegate is used for all deep links into an app. You could set up for example your own scheme that your app conforms to. And you can send url type links with your custom scheme into your app from the browser for example.
To do this just Open Xcode, go to Project Settings -> Info, and add inside ‘The URL Types” section a new URL scheme. Add something of the sort of com.myApp in order for it to be as unizue as possible. Then you can just type into a browser com.myApp://main and handle that in the appDelegate.
Edit: It says so in their docs that you can present a prompt inside the app for the user to input the email. Where the user opens his email from isn't really your concern as long as your dynamic link is set up properly.