Set up Amplify Auth
The Amplify Auth category provides an interface for authenticating a user. Behind the scenes, it provides the necessary authorization to the other Amplify categories. It comes with default, built-in support for Amazon Cognito User Pool and Identity Pool. The Amplify CLI helps you create and configure the auth category with an authentication provider.
Goal
To setup and configure your application with Amplify Auth and go through a simple api to check the current auth session.
Prerequisites
- An iOS application targeting at least iOS 11.0 with Amplify libraries integrated
- For a full example of please follow the project setup walkthrough
Install Amplify Libraries
-
To install Amplify Libraries in your application, open your project in Xcode and select File > Add Packages....
-
Enter the Amplify iOS GitHub repo URL (
https://github.com/aws-amplify/amplify-swift
) into the search bar and click Add Package.
- Lastly, choose AWSCognitoAuthPlugin and Amplify. Then click Add Package.
To install Amplify Auth to your application, add AmplifyPlugins/AWSCognitoAuthPlugin
to your Podfile
. Your Podfile
should look similar to:
target 'MyAmplifyApp' do use_frameworks! pod 'Amplify' pod 'AmplifyPlugins/AWSCognitoAuthPlugin'end
To install, download and resolve these pods, execute the command:
pod install --repo-update
Now you can open your project by opening the .xcworkspace
file using the following command:
xed .
Set Up Backend Resources
The most common way to use Authentication with Amplify is via the Amplify CLI, which allows you to create new Amazon Cognito resources or import existing ones. However, you can also use the Amplify Studio console to configure authentication or use the Amplify.configure()
method to set up authentication with existing resources.
Prerequisites: Install and configure the Amplify CLI in addition to the Amplify libraries and necessary dependencies.
To start provisioning auth resources in the backend, go to your project directory and execute the command:
amplify add auth
Enter the following when prompted:
? Do you want to use the default authentication and security configuration? `Default configuration`? How do you want users to be able to sign in? `Username`? Do you want to configure advanced settings? `No, I am done.`
If you have previously enabled an Amplify category that uses Auth behind the scenes (e.g. API category), you can run the
amplify update auth
command to edit your configuration if needed.
To push your changes to the cloud, execute the command:
amplify push
Upon completion, amplifyconfiguration.json
should be updated to reference provisioned backend auth resources. Note that these files should already be a part of your project if you followed the Project setup walkthrough.
Prerequisites: Install and configure the Amplify CLI in addition to the Amplify libraries and necessary dependencies.
To import existing Amazon Cognito resources into your Amplify project, execute the command:
amplify import auth
? What type of auth resource do you want to import? Cognito User Pool and Identity Pool Cognito User Pool only
Once you've selected an option, you'll be able to search for and import an existing Cognito User Pool and Identity Pool (or User Pool only) within your AWS account. The amplify import auth
command will also do the following:
- Automatically populate your Amplify Library configuration file (
awsconfiguration.json
) with your chosen Amazon Cognito resource information - Provide your designated existing Cognito resource as the authentication & authorization mechanism for all auth-dependent categories (API, Storage and more)
- Enable Lambda functions to access the chosen Cognito resource if you permit it
If you have previously enabled an Amplify category that uses Auth behind the scenes (e.g. API category), you can run the
amplify update auth
command to edit your configuration if needed.
After configuring your Authentication options, update your backend and deploy the service by running the push
command:
amplify push
Upon completion, amplifyconfiguration.json
should be updated to reference provisioned backend auth resources.
Now, the authentication service has been deployed and you can start using it. To view the deployed services in your project at any time, go to Amplify Console by running the following command:
amplify console
For more details, see how to Use an existing Cognito User Pool and Identity Pool.
Prerequisites: Install and configure the Amplify CLI in addition to the Amplify libraries and necessary dependencies.
Amplify Studio allows you create auth resources, set up authorization rules, implement Multi-factor authentication (MFA), and more via an intuitive UI. To set up Authentication through the Amplify Studio, take the following steps:
- Sign in to the AWS Management Console and open AWS Amplify.
- In the navigation pane, choose an application.
- On the application information page, choose the Backend environments tab, then choose Launch Studio.
- On the Set up menu, choose Authentication.
- In the Configure log in section, choose a login mechanism to add from the Add login mechanism list. Valid options are Username, Phone number, Facebook, Google, Amazon, and Sign in with Apple. If you choose one of the social sign-in mechanisms (i.e. Facebook, Google, Amazon, or Sign in with Apple), you will also need to enter your App ID, App Secret, and redirect URLs.
- (Optional) Add multi-factor authentication (MFA). MFA is set to Off by default. To turn on MFA, do the following in the Multi-factor authentication section:
- Choose Enforced to require MFA for all users or choose Optional to allow individual users to enable MFA.
- (Optional) Choose SMS, and enter your SMS message.
- (Optional) Choose Authenticator Application if you want your app to load with an authentication flow that includes sign up and sign in.
- In the Configure sign up section, expand Password protection settings and customize the password policy settings to enforce. u6. Choose Save and Deploy. This starts a CloudFormation deployment with the progress displayed in the upper right corner of the page.
- After creating and configuring your auth resources, you'll need to pull them down from Amplify Studio. To do so, simply click on "Local setup instructions" in the upper right hand corner of the Studio console and execute the CLI command it provides at the root directory of your app.
You can also import existing Amazon Cognito resources and manage users and groups through the Amplify Studio UI.
If you are not using the Amplify CLI, existing Authentication resources from AWS (e.g. Amazon Cognito UserPools or Identity Pools) can be used with the Amplify Libraries by manually creating a configuration file (amplifyconfiguration.json
) and then updating the associated Plugin within it:
{ "auth": { "plugins": { "awsCognitoAuthPlugin": { "IdentityManager": { "Default": {} }, "CredentialsProvider": { "CognitoIdentity": { "Default": { "PoolId": "[COGNITO IDENTITY POOL ID]", "Region": "[REGION]" } } }, "CognitoUserPool": { "Default": { "PoolId": "[COGNITO USER POOL ID]", "AppClientId": "[COGNITO USER POOL APP CLIENT ID]", "Region": "[REGION]" } }, "Auth": { "Default": { "authenticationFlowType": "USER_SRP_AUTH", "socialProviders": [], "usernameAttributes": [], "signupAttributes": [ "[SIGNUP MECHANISM]" ], "passwordProtectionSettings": { "passwordPolicyMinLength": [PASSWORD LENGTH], "passwordPolicyCharacters": [] }, "mfaConfiguration": "OFF", "mfaTypes": [ "[MFA TYPE]" ], "verificationMechanisms": [ "[VERIFICATION MECHANISM]" ], "OAuth": { "WebDomain": "[YOUR COGNITO DOMAIN ]", "AppClientId": "[COGNITO USER POOL APP CLIENT ID]", "SignInRedirectURI": "[CUSTOM REDIRECT SCHEME AFTER SIGN IN, e.g. myapp://]", "SignOutRedirectURI": "[CUSTOM REDIRECT SCHEME AFTER SIGN OUT, e.g. myapp://]", "Scopes": [ "phone", "email", "openid", "profile", "aws.cognito.signin.user.admin" ] } } } } } }}
For more information on Plugins, see the instructions on installing Amplify Libraries.
- CredentialsProvider:
- Cognito Identity:
- Default:
- PoolID: ID of the Amazon Cognito Identity Pool (e.g.
us-east-1:123e4567-e89b-12d3-a456-426614174000
) - Region: AWS Region where the resources are provisioned (e.g.
us-east-1
)
- PoolID: ID of the Amazon Cognito Identity Pool (e.g.
- Default:
- Cognito Identity:
- CognitoUserPool:
- Default:
- PoolId: ID of the Amazon Cognito User Pool (e.g.
us-east-1_abcdefghi
) - AppClientId: ID for the client used to authenticate against the user pool
- Region: AWS Region where the resources are provisioned (e.g.
us-east-1
)
- PoolId: ID of the Amazon Cognito User Pool (e.g.
- Default:
- Auth:
- Default:
- authenticationFlowType: The authentication flow type, takes values
USER_SRP_AUTH
,CUSTOM_AUTH
, andUSER_PASSWORD_AUTH
. Default isUSER_SRP_AUTH
. - OAuth: Hosted UI Configuration (only include this if using the Hosted UI flow)
- Scopes: Scopes should match the scopes enables in Cognito under "App client settings"
- authenticationFlowType: The authentication flow type, takes values
- Default:
If you are using a Cognito User Pool without a Cognito Identity Pool, you can omit the CredentialsProvider section in the configuration.
Initialize Amplify Auth
To initialize the Amplify Auth category, pass in the AWSCognitoAuthPlugin to 'Amplify.add()'. When you are done calling add()
on each category that you need, you finish configuring Amplify by calling Amplify.configure()
.
Add the following imports to the top of your AppDelegate.swift
file:
import Amplifyimport AWSCognitoAuthPlugin
import Amplifyimport AmplifyPlugins
Add the following code
Create a custom AppDelegate
, and add to your application:didFinishLaunchingWithOptions
method
class AppDelegate: NSObject, UIApplicationDelegate { func application( _ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]? ) -> Bool {
do { try Amplify.add(plugin: AWSCognitoAuthPlugin()) try Amplify.configure() print("Amplify configured with auth plugin") } catch { print("Failed to initialize Amplify with \(error)") }
return true }}
Then in the App
scene, use UIApplicationDelegateAdaptor
property wrapper to use your custom AppDelegate
@mainstruct MyAmplifyApp: App { @UIApplicationDelegateAdaptor(AppDelegate.self) var appDelegate
var body: some Scene { WindowGroup { ContentView() } }}
Add to your AppDelegate's application:didFinishLaunchingWithOptions
method
func application( _ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?) -> Bool {
do { try Amplify.add(plugin: AWSCognitoAuthPlugin()) try Amplify.configure() print("Amplify configured with auth plugin") } catch { print("Failed to initialize Amplify with \(error)") }
return true}
Upon building and running this application you should see the following in your console window:
Amplify configured with auth plugin
Check the current auth session
You can now check the current auth session.
func fetchCurrentAuthSession() { _ = Amplify.Auth.fetchAuthSession { result in switch result { case .success(let session): print("Is user signed in - \(session.isSignedIn)") case .failure(let error): print("Fetch session failed with error \(error)") } }}
func fetchCurrentAuthSession() -> AnyCancellable { Amplify.Auth.fetchAuthSession().resultPublisher .sink { if case let .failure(authError) = $0 { print("Fetch session failed with error \(authError)") } } receiveValue: { session in print("Is user signed in - \(session.isSignedIn)") }}
The isSignedIn
property of the authSession
will be false since you haven't signed in to the category yet.
Next Steps
Congratulations! You've successfully setup AWS Cognito Auth plugin. Check out the following links to see other Amplify Auth use cases: