# Core Interfaces / Classes

# ClientRegistration

ClientRegistration is a representation of a client registered with an OAuth 2.0 or OpenID Connect 1.0 Provider.

A client registration holds information, such as client id, client secret, authorization grant type, redirect URI, scope(s), authorization URI, token URI, and other details.

ClientRegistration and its properties are defined as follows:

public final class ClientRegistration {
	private String registrationId;	(1)
	private String clientId;	(2)
	private String clientSecret;	(3)
	private ClientAuthenticationMethod clientAuthenticationMethod;	(4)
	private AuthorizationGrantType authorizationGrantType;	(5)
	private String redirectUri;	(6)
	private Set<String> scopes;	(7)
	private ProviderDetails providerDetails;
	private String clientName;	(8)

	public class ProviderDetails {
		private String authorizationUri;	(9)
		private String tokenUri;	(10)
		private UserInfoEndpoint userInfoEndpoint;
		private String jwkSetUri;	(11)
		private String issuerUri;	(12)
		private Map<String, Object> configurationMetadata;  (13)

		public class UserInfoEndpoint {
			private String uri;	(14)
			private AuthenticationMethod authenticationMethod;  (15)
			private String userNameAttributeName;	(16)

		}
	}
}
1 registrationId: The ID that uniquely identifies the ClientRegistration.
2 clientId: The client identifier.
3 clientSecret: The client secret.
4 clientAuthenticationMethod: The method used to authenticate the Client with the Provider.
The supported values are client_secret_basic, client_secret_post, private_key_jwt, client_secret_jwt and none (public clients) (opens new window).
5 authorizationGrantType: The OAuth 2.0 Authorization Framework defines four Authorization Grant (opens new window) types.
The supported values are authorization_code, client_credentials, password, as well as, extension grant type urn:ietf:params:oauth:grant-type:jwt-bearer.
6 redirectUri: The client’s registered redirect URI that the Authorization Server redirects the end-user’s user-agent
to after the end-user has authenticated and authorized access to the client.
7 scopes: The scope(s) requested by the client during the Authorization Request flow, such as openid, email, or profile.
8 clientName: A descriptive name used for the client.
The name may be used in certain scenarios, such as when displaying the name of the client in the auto-generated login page.
9 authorizationUri: The Authorization Endpoint URI for the Authorization Server.
10 tokenUri: The Token Endpoint URI for the Authorization Server.
11 jwkSetUri: The URI used to retrieve the JSON Web Key (JWK) (opens new window) Set from the Authorization Server,
which contains the cryptographic key(s) used to verify the JSON Web Signature (JWS) (opens new window) of the ID Token and optionally the UserInfo Response.
12 issuerUri: Returns the issuer identifier uri for the OpenID Connect 1.0 provider or the OAuth 2.0 Authorization Server.
13 configurationMetadata: The OpenID Provider Configuration Information (opens new window).
This information will only be available if the Spring Boot 2.x property spring.security.oauth2.client.provider.[providerId].issuerUri is configured.
14 (userInfoEndpoint)uri: The UserInfo Endpoint URI used to access the claims/attributes of the authenticated end-user.
15 (userInfoEndpoint)authenticationMethod: The authentication method used when sending the access token to the UserInfo Endpoint.
The supported values are header, form and query.
16 userNameAttributeName: The name of the attribute returned in the UserInfo Response that references the Name or Identifier of the end-user.

A ClientRegistration can be initially configured using discovery of an OpenID Connect Provider’s Configuration endpoint (opens new window) or an Authorization Server’s Metadata endpoint (opens new window).

ClientRegistrations provides convenience methods for configuring a ClientRegistration in this way, as can be seen in the following example:

Java

ClientRegistration clientRegistration =
	ClientRegistrations.fromIssuerLocation("https://idp.example.com/issuer").build();

Kotlin

val clientRegistration = ClientRegistrations.fromIssuerLocation("https://idp.example.com/issuer").build()

The above code will query in series [https://idp.example.com/issuer/.well-known/openid-configuration](https://idp.example.com/issuer/.well-known/openid-configuration), and then [https://idp.example.com/.well-known/openid-configuration/issuer](https://idp.example.com/.well-known/openid-configuration/issuer), and finally [https://idp.example.com/.well-known/oauth-authorization-server/issuer](https://idp.example.com/.well-known/oauth-authorization-server/issuer), stopping at the first to return a 200 response.

As an alternative, you can use ClientRegistrations.fromOidcIssuerLocation() to only query the OpenID Connect Provider’s Configuration endpoint.

# ReactiveClientRegistrationRepository

The ReactiveClientRegistrationRepository serves as a repository for OAuth 2.0 / OpenID Connect 1.0 ClientRegistration(s).

Client registration information is ultimately stored and owned by the associated Authorization Server.
This repository provides the ability to retrieve a sub-set of the primary client registration information, which is stored with the Authorization Server.

Spring Boot 2.x auto-configuration binds each of the properties under spring.security.oauth2.client.registration.*[registrationId]* to an instance of ClientRegistration and then composes each of the ClientRegistration instance(s) within a ReactiveClientRegistrationRepository.

The default implementation of ReactiveClientRegistrationRepository is InMemoryReactiveClientRegistrationRepository.

The auto-configuration also registers the ReactiveClientRegistrationRepository as a @Bean in the ApplicationContext so that it is available for dependency-injection, if needed by the application.

The following listing shows an example:

Java

@Controller
public class OAuth2ClientController {

	@Autowired
	private ReactiveClientRegistrationRepository clientRegistrationRepository;

	@GetMapping("/")
	public Mono<String> index() {
		return this.clientRegistrationRepository.findByRegistrationId("okta")
				...
				.thenReturn("index");
	}
}

Kotlin

@Controller
class OAuth2ClientController {

    @Autowired
    private lateinit var clientRegistrationRepository: ReactiveClientRegistrationRepository

    @GetMapping("/")
    fun index(): Mono<String> {
        return this.clientRegistrationRepository.findByRegistrationId("okta")
            ...
            .thenReturn("index")
    }
}

# OAuth2AuthorizedClient

OAuth2AuthorizedClient is a representation of an Authorized Client. A client is considered to be authorized when the end-user (Resource Owner) has granted authorization to the client to access its protected resources.

OAuth2AuthorizedClient serves the purpose of associating an OAuth2AccessToken (and optional OAuth2RefreshToken) to a ClientRegistration (client) and resource owner, who is the Principal end-user that granted the authorization.

# ServerOAuth2AuthorizedClientRepository / ReactiveOAuth2AuthorizedClientService

ServerOAuth2AuthorizedClientRepository is responsible for persisting OAuth2AuthorizedClient(s) between web requests. Whereas, the primary role of ReactiveOAuth2AuthorizedClientService is to manage OAuth2AuthorizedClient(s) at the application-level.

From a developer perspective, the ServerOAuth2AuthorizedClientRepository or ReactiveOAuth2AuthorizedClientService provides the capability to lookup an OAuth2AccessToken associated with a client so that it may be used to initiate a protected resource request.

The following listing shows an example:

Java

@Controller
public class OAuth2ClientController {

	@Autowired
	private ReactiveOAuth2AuthorizedClientService authorizedClientService;

	@GetMapping("/")
	public Mono<String> index(Authentication authentication) {
		return this.authorizedClientService.loadAuthorizedClient("okta", authentication.getName())
				.map(OAuth2AuthorizedClient::getAccessToken)
				...
				.thenReturn("index");
	}
}

Kotlin

@Controller
class OAuth2ClientController {

    @Autowired
    private lateinit var authorizedClientService: ReactiveOAuth2AuthorizedClientService

    @GetMapping("/")
    fun index(authentication: Authentication): Mono<String> {
        return this.authorizedClientService.loadAuthorizedClient<OAuth2AuthorizedClient>("okta", authentication.name)
            .map { it.accessToken }
            ...
            .thenReturn("index")
    }
}
Spring Boot 2.x auto-configuration registers an ServerOAuth2AuthorizedClientRepository and/or ReactiveOAuth2AuthorizedClientService @Bean in the ApplicationContext.
However, the application may choose to override and register a custom ServerOAuth2AuthorizedClientRepository or ReactiveOAuth2AuthorizedClientService @Bean.

The default implementation of ReactiveOAuth2AuthorizedClientService is InMemoryReactiveOAuth2AuthorizedClientService, which stores OAuth2AuthorizedClient(s) in-memory.

Alternatively, the R2DBC implementation R2dbcReactiveOAuth2AuthorizedClientService may be configured for persisting OAuth2AuthorizedClient(s) in a database.

R2dbcReactiveOAuth2AuthorizedClientService depends on the table definition described in OAuth 2.0 Client Schema.

# ReactiveOAuth2AuthorizedClientManager / ReactiveOAuth2AuthorizedClientProvider

The ReactiveOAuth2AuthorizedClientManager is responsible for the overall management of OAuth2AuthorizedClient(s).

The primary responsibilities include:

  • Authorizing (or re-authorizing) an OAuth 2.0 Client, using a ReactiveOAuth2AuthorizedClientProvider.

  • Delegating the persistence of an OAuth2AuthorizedClient, typically using a ReactiveOAuth2AuthorizedClientService or ServerOAuth2AuthorizedClientRepository.

  • Delegating to a ReactiveOAuth2AuthorizationSuccessHandler when an OAuth 2.0 Client has been successfully authorized (or re-authorized).

  • Delegating to a ReactiveOAuth2AuthorizationFailureHandler when an OAuth 2.0 Client fails to authorize (or re-authorize).

A ReactiveOAuth2AuthorizedClientProvider implements a strategy for authorizing (or re-authorizing) an OAuth 2.0 Client. Implementations will typically implement an authorization grant type, eg. authorization_code, client_credentials, etc.

The default implementation of ReactiveOAuth2AuthorizedClientManager is DefaultReactiveOAuth2AuthorizedClientManager, which is associated with a ReactiveOAuth2AuthorizedClientProvider that may support multiple authorization grant types using a delegation-based composite. The ReactiveOAuth2AuthorizedClientProviderBuilder may be used to configure and build the delegation-based composite.

The following code shows an example of how to configure and build a ReactiveOAuth2AuthorizedClientProvider composite that provides support for the authorization_code, refresh_token, client_credentials and password authorization grant types:

Java

@Bean
public ReactiveOAuth2AuthorizedClientManager authorizedClientManager(
		ReactiveClientRegistrationRepository clientRegistrationRepository,
		ServerOAuth2AuthorizedClientRepository authorizedClientRepository) {

	ReactiveOAuth2AuthorizedClientProvider authorizedClientProvider =
			ReactiveOAuth2AuthorizedClientProviderBuilder.builder()
					.authorizationCode()
					.refreshToken()
					.clientCredentials()
					.password()
					.build();

	DefaultReactiveOAuth2AuthorizedClientManager authorizedClientManager =
			new DefaultReactiveOAuth2AuthorizedClientManager(
					clientRegistrationRepository, authorizedClientRepository);
	authorizedClientManager.setAuthorizedClientProvider(authorizedClientProvider);

	return authorizedClientManager;
}

Kotlin

@Bean
fun authorizedClientManager(
        clientRegistrationRepository: ReactiveClientRegistrationRepository,
        authorizedClientRepository: ServerOAuth2AuthorizedClientRepository): ReactiveOAuth2AuthorizedClientManager {
    val authorizedClientProvider: ReactiveOAuth2AuthorizedClientProvider = ReactiveOAuth2AuthorizedClientProviderBuilder.builder()
            .authorizationCode()
            .refreshToken()
            .clientCredentials()
            .password()
            .build()
    val authorizedClientManager = DefaultReactiveOAuth2AuthorizedClientManager(
            clientRegistrationRepository, authorizedClientRepository)
    authorizedClientManager.setAuthorizedClientProvider(authorizedClientProvider)
    return authorizedClientManager
}

When an authorization attempt succeeds, the DefaultReactiveOAuth2AuthorizedClientManager will delegate to the ReactiveOAuth2AuthorizationSuccessHandler, which (by default) will save the OAuth2AuthorizedClient via the ServerOAuth2AuthorizedClientRepository. In the case of a re-authorization failure, eg. a refresh token is no longer valid, the previously saved OAuth2AuthorizedClient will be removed from the ServerOAuth2AuthorizedClientRepository via the RemoveAuthorizedClientReactiveOAuth2AuthorizationFailureHandler. The default behaviour may be customized via setAuthorizationSuccessHandler(ReactiveOAuth2AuthorizationSuccessHandler) and setAuthorizationFailureHandler(ReactiveOAuth2AuthorizationFailureHandler).

The DefaultReactiveOAuth2AuthorizedClientManager is also associated with a contextAttributesMapper of type Function<OAuth2AuthorizeRequest, Mono<Map<String, Object>>>, which is responsible for mapping attribute(s) from the OAuth2AuthorizeRequest to a Map of attributes to be associated to the OAuth2AuthorizationContext. This can be useful when you need to supply a ReactiveOAuth2AuthorizedClientProvider with required (supported) attribute(s), eg. the PasswordReactiveOAuth2AuthorizedClientProvider requires the resource owner’s username and password to be available in OAuth2AuthorizationContext.getAttributes().

The following code shows an example of the contextAttributesMapper:

Java

@Bean
public ReactiveOAuth2AuthorizedClientManager authorizedClientManager(
		ReactiveClientRegistrationRepository clientRegistrationRepository,
		ServerOAuth2AuthorizedClientRepository authorizedClientRepository) {

	ReactiveOAuth2AuthorizedClientProvider authorizedClientProvider =
			ReactiveOAuth2AuthorizedClientProviderBuilder.builder()
					.password()
					.refreshToken()
					.build();

	DefaultReactiveOAuth2AuthorizedClientManager authorizedClientManager =
			new DefaultReactiveOAuth2AuthorizedClientManager(
					clientRegistrationRepository, authorizedClientRepository);
	authorizedClientManager.setAuthorizedClientProvider(authorizedClientProvider);

	// Assuming the `username` and `password` are supplied as `ServerHttpRequest` parameters,
	// map the `ServerHttpRequest` parameters to `OAuth2AuthorizationContext.getAttributes()`
	authorizedClientManager.setContextAttributesMapper(contextAttributesMapper());

	return authorizedClientManager;
}

private Function<OAuth2AuthorizeRequest, Mono<Map<String, Object>>> contextAttributesMapper() {
	return authorizeRequest -> {
		Map<String, Object> contextAttributes = Collections.emptyMap();
		ServerWebExchange exchange = authorizeRequest.getAttribute(ServerWebExchange.class.getName());
		ServerHttpRequest request = exchange.getRequest();
		String username = request.getQueryParams().getFirst(OAuth2ParameterNames.USERNAME);
		String password = request.getQueryParams().getFirst(OAuth2ParameterNames.PASSWORD);
		if (StringUtils.hasText(username) && StringUtils.hasText(password)) {
			contextAttributes = new HashMap<>();

			// `PasswordReactiveOAuth2AuthorizedClientProvider` requires both attributes
			contextAttributes.put(OAuth2AuthorizationContext.USERNAME_ATTRIBUTE_NAME, username);
			contextAttributes.put(OAuth2AuthorizationContext.PASSWORD_ATTRIBUTE_NAME, password);
		}
		return Mono.just(contextAttributes);
	};
}

Kotlin

@Bean
fun authorizedClientManager(
        clientRegistrationRepository: ReactiveClientRegistrationRepository,
        authorizedClientRepository: ServerOAuth2AuthorizedClientRepository): ReactiveOAuth2AuthorizedClientManager {
    val authorizedClientProvider: ReactiveOAuth2AuthorizedClientProvider = ReactiveOAuth2AuthorizedClientProviderBuilder.builder()
            .password()
            .refreshToken()
            .build()
    val authorizedClientManager = DefaultReactiveOAuth2AuthorizedClientManager(
            clientRegistrationRepository, authorizedClientRepository)
    authorizedClientManager.setAuthorizedClientProvider(authorizedClientProvider)

    // Assuming the `username` and `password` are supplied as `ServerHttpRequest` parameters,
    // map the `ServerHttpRequest` parameters to `OAuth2AuthorizationContext.getAttributes()`
    authorizedClientManager.setContextAttributesMapper(contextAttributesMapper())
    return authorizedClientManager
}

private fun contextAttributesMapper(): Function<OAuth2AuthorizeRequest, Mono<MutableMap<String, Any>>> {
    return Function { authorizeRequest ->
        var contextAttributes: MutableMap<String, Any> = mutableMapOf()
        val exchange: ServerWebExchange = authorizeRequest.getAttribute(ServerWebExchange::class.java.name)!!
        val request: ServerHttpRequest = exchange.request
        val username: String? = request.queryParams.getFirst(OAuth2ParameterNames.USERNAME)
        val password: String? = request.queryParams.getFirst(OAuth2ParameterNames.PASSWORD)
        if (StringUtils.hasText(username) && StringUtils.hasText(password)) {
            contextAttributes = hashMapOf()

            // `PasswordReactiveOAuth2AuthorizedClientProvider` requires both attributes
            contextAttributes[OAuth2AuthorizationContext.USERNAME_ATTRIBUTE_NAME] = username!!
            contextAttributes[OAuth2AuthorizationContext.PASSWORD_ATTRIBUTE_NAME] = password!!
        }
        Mono.just(contextAttributes)
    }
}

The DefaultReactiveOAuth2AuthorizedClientManager is designed to be used within the context of a ServerWebExchange. When operating outside of a ServerWebExchange context, use AuthorizedClientServiceReactiveOAuth2AuthorizedClientManager instead.

A service application is a common use case for when to use an AuthorizedClientServiceReactiveOAuth2AuthorizedClientManager. Service applications often run in the background, without any user interaction, and typically run under a system-level account instead of a user account. An OAuth 2.0 Client configured with the client_credentials grant type can be considered a type of service application.

The following code shows an example of how to configure an AuthorizedClientServiceReactiveOAuth2AuthorizedClientManager that provides support for the client_credentials grant type:

Java

@Bean
public ReactiveOAuth2AuthorizedClientManager authorizedClientManager(
		ReactiveClientRegistrationRepository clientRegistrationRepository,
		ReactiveOAuth2AuthorizedClientService authorizedClientService) {

	ReactiveOAuth2AuthorizedClientProvider authorizedClientProvider =
			ReactiveOAuth2AuthorizedClientProviderBuilder.builder()
					.clientCredentials()
					.build();

	AuthorizedClientServiceReactiveOAuth2AuthorizedClientManager authorizedClientManager =
			new AuthorizedClientServiceReactiveOAuth2AuthorizedClientManager(
					clientRegistrationRepository, authorizedClientService);
	authorizedClientManager.setAuthorizedClientProvider(authorizedClientProvider);

	return authorizedClientManager;
}

Kotlin

@Bean
fun authorizedClientManager(
        clientRegistrationRepository: ReactiveClientRegistrationRepository,
        authorizedClientService: ReactiveOAuth2AuthorizedClientService): ReactiveOAuth2AuthorizedClientManager {
    val authorizedClientProvider: ReactiveOAuth2AuthorizedClientProvider = ReactiveOAuth2AuthorizedClientProviderBuilder.builder()
            .clientCredentials()
            .build()
    val authorizedClientManager = AuthorizedClientServiceReactiveOAuth2AuthorizedClientManager(
            clientRegistrationRepository, authorizedClientService)
    authorizedClientManager.setAuthorizedClientProvider(authorizedClientProvider)
    return authorizedClientManager
}

OAuth2 ClientOAuth2 Authorization Grants