How to get username from AWS Cognito - Swift - swift

Question

Q & A Style: See Answer Below
How Can I get the username from a user logged in with Cognito?
I've done this and my user is logged in, now what?
AWSAuthUIViewController.presentViewController(
with: self.navigationController!,
configuration: config, completionHandler: { (provider: AWSSignInProvider, error: Error?) in
if error == nil {
//get parameters
}
} else {
print(error as Any)
}
})
}

Answer 1

Prerequisites:
App registered with MobileHub
Cognito Setup in MobileHub
Mobilehub integrated with Swift Project using AWS SDK
If you're like me, you did this with little to no difficulty and now you're stuck trying to get the username and other parameters from the logged in user. There are a lot of answers, but thus far, I haven't stumbled upon one that gets you all the way there.
I was able to piece this together from various sources:
func getUsername() {
//to check if user is logged in with Cognito... not sure if this is necessary
let identityManager = AWSIdentityManager.default()
let identityProvider = identityManager.credentialsProvider.identityProvider.identityProviderName
if identityProvider == "cognito-identity.amazonaws.com" {
print("************LOGGED IN WITH COGNITO************")
let serviceConfiguration = AWSServiceConfiguration(region: .USWest2, credentialsProvider: nil)
let userPoolConfiguration = AWSCognitoIdentityUserPoolConfiguration(clientId: "YourClientID", clientSecret: "YourSecretKey", poolId: "YourPoolID")
AWSCognitoIdentityUserPool.register(with: serviceConfiguration, userPoolConfiguration: userPoolConfiguration, forKey: "YourPoolName (typically formatted as YourAppName_userpoool_MOBILEHUB_12345678")
let pool = AWSCognitoIdentityUserPool(forKey: "YourPoolName")
// the following line doesn't seem to be necessary and isn't used so I've commented it out, but it is included in official documentation
// let credentialsProvider = AWSCognitoCredentialsProvider(regionType: .USWest2, identityPoolId: "YourPoolID", identityProviderManager:pool)
if let username = pool.currentUser()?.username {
print("Username Retrieved Successfully: \(username)")
} else {
print("Error getting username from current user - attempt to get user")
let user = pool.getUser()
let username = user.username
print("Username: \(username)")
}
}
}
To get your ClientID, Secret Key, and PoolID, check your awsconfiguration.json
To get your PoolName, login to MobileHub, and in your project's backend, go to User Sign in, click Email and Password, then click Edit in Cognito. The following page will have your Pool Name as "YourAppName_userpool_MOBILEHUB_12345678"
Edit: To get all of the attributes as well:
if let userFromPool = pool.currentUser() {
userFromPool.getDetails().continueOnSuccessWith(block: { (task) -> Any? in
DispatchQueue.main.async {
if let error = task.error as NSError? {
print("Error getting user attributes from Cognito: \(error)")
} else {
let response = task.result
if let userAttributes = response?.userAttributes {
print("user attributes found: \(userAttributes)")
for attribute in userAttributes {
if attribute.name == "email" {
if let email = attribute.value {
print("User Email: \(email)")
}
}
}

Answer 2

If you're using Cognito User Pools, you can use this:
import AWSUserPoolsSignIn
AWSCognitoUserPoolsSignInProvider.sharedInstance()
.getUserPool()
.currentUser()?
.username