Polish gh-350

oauth2-authorization-server/src/main/java/org/springframework/security/oauth2/server/authorization/client/RegisteredClient.java

@@ -482,11 +482,10 @@ public class RegisteredClient implements Serializable {
 				this.clientName = this.id;
 			}
 			if (CollectionUtils.isEmpty(this.clientAuthenticationMethods)) {
-				this.clientAuthenticationMethods.add(ClientAuthenticationMethod.BASIC);
+				this.clientAuthenticationMethods.add(ClientAuthenticationMethod.CLIENT_SECRET_BASIC);
 			}
 			validateScopes();
 			validateRedirectUris();
-			upgradeClientAuthenticationMethods();
 			return create();
 		}
 
@@ -545,17 +544,6 @@ public class RegisteredClient implements Serializable {
 			}
 		}
 
-		private void upgradeClientAuthenticationMethods() {
-			if (this.clientAuthenticationMethods.contains(ClientAuthenticationMethod.BASIC)) {
-				this.clientAuthenticationMethods.remove(ClientAuthenticationMethod.BASIC);
-				this.clientAuthenticationMethods.add(ClientAuthenticationMethod.CLIENT_SECRET_BASIC);
-			}
-			if (this.clientAuthenticationMethods.contains(ClientAuthenticationMethod.POST)) {
-				this.clientAuthenticationMethods.remove(ClientAuthenticationMethod.POST);
-				this.clientAuthenticationMethods.add(ClientAuthenticationMethod.CLIENT_SECRET_POST);
-			}
-		}
-
 		private static boolean validateRedirectUri(String redirectUri) {
 			try {
 				URI validRedirectUri = new URI(redirectUri);

oauth2-authorization-server/src/main/java/org/springframework/security/oauth2/server/authorization/oidc/authentication/OidcClientRegistrationAuthenticationProvider.java

@@ -141,12 +141,10 @@ public class OidcClientRegistrationAuthenticationProvider implements Authenticat
 				.clientSecret(CLIENT_SECRET_GENERATOR.generateKey())
 				.clientName(clientRegistration.getClientName());
 
-		if ("client_secret_post".equals(clientRegistration.getTokenEndpointAuthenticationMethod())) {
-			// TODO: Use ClientAuthenticationMethod.CLIENT_SECRET_POST in Spring Security 5.5.0
-			builder.clientAuthenticationMethod(ClientAuthenticationMethod.POST);
+		if (ClientAuthenticationMethod.CLIENT_SECRET_POST.getValue().equals(clientRegistration.getTokenEndpointAuthenticationMethod())) {
+			builder.clientAuthenticationMethod(ClientAuthenticationMethod.CLIENT_SECRET_POST);
 		} else {
-			// TODO: Use ClientAuthenticationMethod.CLIENT_SECRET_BASIC in Spring Security 5.5.0
-			builder.clientAuthenticationMethod(ClientAuthenticationMethod.BASIC);
+			builder.clientAuthenticationMethod(ClientAuthenticationMethod.CLIENT_SECRET_BASIC);
 		}
 
 		// TODO Validate redirect_uris and throw OAuth2ErrorCodes2.INVALID_REDIRECT_URI on error

oauth2-authorization-server/src/main/java/org/springframework/security/oauth2/server/authorization/oidc/web/OidcProviderConfigurationEndpointFilter.java

@@ -19,6 +19,7 @@ import org.springframework.http.HttpMethod;
 import org.springframework.http.MediaType;
 import org.springframework.http.server.ServletServerHttpResponse;
 import org.springframework.security.oauth2.core.AuthorizationGrantType;
+import org.springframework.security.oauth2.core.ClientAuthenticationMethod;
 import org.springframework.security.oauth2.core.endpoint.OAuth2AuthorizationResponseType;
 import org.springframework.security.oauth2.core.oidc.OidcProviderConfiguration;
 import org.springframework.security.oauth2.core.oidc.OidcScopes;
@@ -79,8 +80,8 @@ public class OidcProviderConfigurationEndpointFilter extends OncePerRequestFilte
 				.issuer(this.providerSettings.issuer())
 				.authorizationEndpoint(asUrl(this.providerSettings.issuer(), this.providerSettings.authorizationEndpoint()))
 				.tokenEndpoint(asUrl(this.providerSettings.issuer(), this.providerSettings.tokenEndpoint()))
-				.tokenEndpointAuthenticationMethod("client_secret_basic")	// TODO: Use ClientAuthenticationMethod.CLIENT_SECRET_BASIC in Spring Security 5.5.0
-				.tokenEndpointAuthenticationMethod("client_secret_post")	// TODO: Use ClientAuthenticationMethod.CLIENT_SECRET_POST in Spring Security 5.5.0
+				.tokenEndpointAuthenticationMethod(ClientAuthenticationMethod.CLIENT_SECRET_BASIC.getValue())
+				.tokenEndpointAuthenticationMethod(ClientAuthenticationMethod.CLIENT_SECRET_POST.getValue())
 				.jwkSetUrl(asUrl(this.providerSettings.issuer(), this.providerSettings.jwkSetEndpoint()))
 				.responseType(OAuth2AuthorizationResponseType.CODE.getValue())
 				.grantType(AuthorizationGrantType.AUTHORIZATION_CODE.getValue())

oauth2-authorization-server/src/main/java/org/springframework/security/oauth2/server/authorization/web/OAuth2AuthorizationServerMetadataEndpointFilter.java

@@ -28,6 +28,7 @@ import org.springframework.http.HttpMethod;
 import org.springframework.http.MediaType;
 import org.springframework.http.server.ServletServerHttpResponse;
 import org.springframework.security.oauth2.core.AuthorizationGrantType;
+import org.springframework.security.oauth2.core.ClientAuthenticationMethod;
 import org.springframework.security.oauth2.core.OAuth2AuthorizationServerMetadata;
 import org.springframework.security.oauth2.core.endpoint.OAuth2AuthorizationResponseType;
 import org.springframework.security.oauth2.core.http.converter.OAuth2AuthorizationServerMetadataHttpMessageConverter;
@@ -101,8 +102,8 @@ public class OAuth2AuthorizationServerMetadataEndpointFilter extends OncePerRequ
 
 	private static Consumer<List<String>> clientAuthenticationMethods() {
 		return (authenticationMethods) -> {
-			authenticationMethods.add("client_secret_basic");	// TODO: Use ClientAuthenticationMethod.CLIENT_SECRET_BASIC in Spring Security 5.5.0
-			authenticationMethods.add("client_secret_post");	// TODO: Use ClientAuthenticationMethod.CLIENT_SECRET_POST in Spring Security 5.5.0
+			authenticationMethods.add(ClientAuthenticationMethod.CLIENT_SECRET_BASIC.getValue());
+			authenticationMethods.add(ClientAuthenticationMethod.CLIENT_SECRET_POST.getValue());
 		};
 	}
 

oauth2-authorization-server/src/test/java/org/springframework/security/oauth2/core/OAuth2AuthorizationServerMetadataTests.java

@@ -49,16 +49,16 @@ public class OAuth2AuthorizationServerMetadataTests {
 				.issuer("https://example.com/issuer1")
 				.authorizationEndpoint("https://example.com/issuer1/oauth2/authorize")
 				.tokenEndpoint("https://example.com/issuer1/oauth2/token")
-				.tokenEndpointAuthenticationMethod("client_secret_basic")
+				.tokenEndpointAuthenticationMethod(ClientAuthenticationMethod.CLIENT_SECRET_BASIC.getValue())
 				.jwkSetUrl("https://example.com/issuer1/oauth2/jwks")
 				.scope("openid")
 				.responseType("code")
 				.grantType("authorization_code")
 				.grantType("client_credentials")
 				.tokenRevocationEndpoint("https://example.com/issuer1/oauth2/revoke")
-				.tokenRevocationEndpointAuthenticationMethod("client_secret_basic")
+				.tokenRevocationEndpointAuthenticationMethod(ClientAuthenticationMethod.CLIENT_SECRET_BASIC.getValue())
 				.tokenIntrospectionEndpoint("https://example.com/issuer1/oauth2/introspect")
-				.tokenIntrospectionEndpointAuthenticationMethod("client_secret_basic")
+				.tokenIntrospectionEndpointAuthenticationMethod(ClientAuthenticationMethod.CLIENT_SECRET_BASIC.getValue())
 				.codeChallengeMethod("plain")
 				.codeChallengeMethod("S256")
 				.claim("a-claim", "a-value")
@@ -67,15 +67,15 @@ public class OAuth2AuthorizationServerMetadataTests {
 		assertThat(authorizationServerMetadata.getIssuer()).isEqualTo(url("https://example.com/issuer1"));
 		assertThat(authorizationServerMetadata.getAuthorizationEndpoint()).isEqualTo(url("https://example.com/issuer1/oauth2/authorize"));
 		assertThat(authorizationServerMetadata.getTokenEndpoint()).isEqualTo(url("https://example.com/issuer1/oauth2/token"));
-		assertThat(authorizationServerMetadata.getTokenEndpointAuthenticationMethods()).containsExactly("client_secret_basic");
+		assertThat(authorizationServerMetadata.getTokenEndpointAuthenticationMethods()).containsExactly(ClientAuthenticationMethod.CLIENT_SECRET_BASIC.getValue());
 		assertThat(authorizationServerMetadata.getJwkSetUrl()).isEqualTo(url("https://example.com/issuer1/oauth2/jwks"));
 		assertThat(authorizationServerMetadata.getScopes()).containsExactly("openid");
 		assertThat(authorizationServerMetadata.getResponseTypes()).containsExactly("code");
 		assertThat(authorizationServerMetadata.getGrantTypes()).containsExactlyInAnyOrder("authorization_code", "client_credentials");
 		assertThat(authorizationServerMetadata.getTokenRevocationEndpoint()).isEqualTo(url("https://example.com/issuer1/oauth2/revoke"));
-		assertThat(authorizationServerMetadata.getTokenRevocationEndpointAuthenticationMethods()).containsExactly("client_secret_basic");
+		assertThat(authorizationServerMetadata.getTokenRevocationEndpointAuthenticationMethods()).containsExactly(ClientAuthenticationMethod.CLIENT_SECRET_BASIC.getValue());
 		assertThat(authorizationServerMetadata.getTokenIntrospectionEndpoint()).isEqualTo(url("https://example.com/issuer1/oauth2/introspect"));
-		assertThat(authorizationServerMetadata.getTokenIntrospectionEndpointAuthenticationMethods()).containsExactly("client_secret_basic");
+		assertThat(authorizationServerMetadata.getTokenIntrospectionEndpointAuthenticationMethods()).containsExactly(ClientAuthenticationMethod.CLIENT_SECRET_BASIC.getValue());
 		assertThat(authorizationServerMetadata.getCodeChallengeMethods()).containsExactlyInAnyOrder("plain", "S256");
 		assertThat(authorizationServerMetadata.getClaimAsString("a-claim")).isEqualTo("a-value");
 	}

oauth2-authorization-server/src/test/java/org/springframework/security/oauth2/core/http/converter/OAuth2AuthorizationServerMetadataHttpMessageConverterTests.java

@@ -28,6 +28,7 @@ import org.springframework.http.converter.HttpMessageNotReadableException;
 import org.springframework.http.converter.HttpMessageNotWritableException;
 import org.springframework.mock.http.MockHttpOutputMessage;
 import org.springframework.mock.http.client.MockClientHttpResponse;
+import org.springframework.security.oauth2.core.ClientAuthenticationMethod;
 import org.springframework.security.oauth2.core.OAuth2AuthorizationServerMetadata;
 
 import static org.assertj.core.api.Assertions.assertThat;
@@ -115,15 +116,15 @@ public class OAuth2AuthorizationServerMetadataHttpMessageConverterTests {
 		assertThat(authorizationServerMetadata.getIssuer()).isEqualTo(new URL("https://example.com/issuer1"));
 		assertThat(authorizationServerMetadata.getAuthorizationEndpoint()).isEqualTo(new URL("https://example.com/issuer1/oauth2/authorize"));
 		assertThat(authorizationServerMetadata.getTokenEndpoint()).isEqualTo(new URL("https://example.com/issuer1/oauth2/token"));
-		assertThat(authorizationServerMetadata.getTokenEndpointAuthenticationMethods()).containsExactly("client_secret_basic");
+		assertThat(authorizationServerMetadata.getTokenEndpointAuthenticationMethods()).containsExactly(ClientAuthenticationMethod.CLIENT_SECRET_BASIC.getValue());
 		assertThat(authorizationServerMetadata.getJwkSetUrl()).isEqualTo(new URL("https://example.com/issuer1/oauth2/jwks"));
 		assertThat(authorizationServerMetadata.getScopes()).containsExactly("openid");
 		assertThat(authorizationServerMetadata.getResponseTypes()).containsExactly("code");
 		assertThat(authorizationServerMetadata.getGrantTypes()).containsExactlyInAnyOrder("authorization_code", "client_credentials");
 		assertThat(authorizationServerMetadata.getTokenRevocationEndpoint()).isEqualTo(new URL("https://example.com/issuer1/oauth2/revoke"));
-		assertThat(authorizationServerMetadata.getTokenRevocationEndpointAuthenticationMethods()).containsExactly("client_secret_basic");
+		assertThat(authorizationServerMetadata.getTokenRevocationEndpointAuthenticationMethods()).containsExactly(ClientAuthenticationMethod.CLIENT_SECRET_BASIC.getValue());
 		assertThat(authorizationServerMetadata.getTokenIntrospectionEndpoint()).isEqualTo(new URL("https://example.com/issuer1/oauth2/introspect"));
-		assertThat(authorizationServerMetadata.getTokenIntrospectionEndpointAuthenticationMethods()).containsExactly("client_secret_basic");
+		assertThat(authorizationServerMetadata.getTokenIntrospectionEndpointAuthenticationMethods()).containsExactly(ClientAuthenticationMethod.CLIENT_SECRET_BASIC.getValue());
 		assertThat(authorizationServerMetadata.getCodeChallengeMethods()).containsExactlyInAnyOrder("plain", "S256");
 		assertThat(authorizationServerMetadata.getClaimAsString("custom_claim")).isEqualTo("value");
 		assertThat(authorizationServerMetadata.getClaimAsStringList("custom_collection_claim")).containsExactlyInAnyOrder("value1", "value2");
@@ -161,16 +162,16 @@ public class OAuth2AuthorizationServerMetadataHttpMessageConverterTests {
 						.issuer("https://example.com/issuer1")
 						.authorizationEndpoint("https://example.com/issuer1/oauth2/authorize")
 						.tokenEndpoint("https://example.com/issuer1/oauth2/token")
-						.tokenEndpointAuthenticationMethod("client_secret_basic")
+						.tokenEndpointAuthenticationMethod(ClientAuthenticationMethod.CLIENT_SECRET_BASIC.getValue())
 						.jwkSetUrl("https://example.com/issuer1/oauth2/jwks")
 						.scope("openid")
 						.responseType("code")
 						.grantType("authorization_code")
 						.grantType("client_credentials")
 						.tokenRevocationEndpoint("https://example.com/issuer1/oauth2/revoke")
-						.tokenRevocationEndpointAuthenticationMethod("client_secret_basic")
+						.tokenRevocationEndpointAuthenticationMethod(ClientAuthenticationMethod.CLIENT_SECRET_BASIC.getValue())
 						.tokenIntrospectionEndpoint("https://example.com/issuer1/oauth2/introspect")
-						.tokenIntrospectionEndpointAuthenticationMethod("client_secret_basic")
+						.tokenIntrospectionEndpointAuthenticationMethod(ClientAuthenticationMethod.CLIENT_SECRET_BASIC.getValue())
 						.codeChallengeMethod("plain")
 						.codeChallengeMethod("S256")
 						.claim("custom_claim", "value")

oauth2-authorization-server/src/test/java/org/springframework/security/oauth2/core/oidc/OidcClientRegistrationTests.java

@@ -56,7 +56,7 @@ public class OidcClientRegistrationTests {
 				.clientSecretExpiresAt(clientSecretExpiresAt)
 				.clientName("client-name")
 				.redirectUri("https://client.example.com")
-				.tokenEndpointAuthenticationMethod(ClientAuthenticationMethod.BASIC.getValue())
+				.tokenEndpointAuthenticationMethod(ClientAuthenticationMethod.CLIENT_SECRET_BASIC.getValue())
 				.grantType(AuthorizationGrantType.AUTHORIZATION_CODE.getValue())
 				.grantType(AuthorizationGrantType.CLIENT_CREDENTIALS.getValue())
 				.responseType(OAuth2AuthorizationResponseType.CODE.getValue())
@@ -73,7 +73,7 @@ public class OidcClientRegistrationTests {
 		assertThat(clientRegistration.getClientSecretExpiresAt()).isEqualTo(clientSecretExpiresAt);
 		assertThat(clientRegistration.getClientName()).isEqualTo("client-name");
 		assertThat(clientRegistration.getRedirectUris()).containsOnly("https://client.example.com");
-		assertThat(clientRegistration.getTokenEndpointAuthenticationMethod()).isEqualTo("basic");
+		assertThat(clientRegistration.getTokenEndpointAuthenticationMethod()).isEqualTo(ClientAuthenticationMethod.CLIENT_SECRET_BASIC.getValue());
 		assertThat(clientRegistration.getGrantTypes()).containsExactlyInAnyOrder("authorization_code", "client_credentials");
 		assertThat(clientRegistration.getResponseTypes()).containsOnly("code");
 		assertThat(clientRegistration.getScopes()).containsExactlyInAnyOrder("scope1", "scope2");
@@ -98,7 +98,7 @@ public class OidcClientRegistrationTests {
 		claims.put(OidcClientMetadataClaimNames.CLIENT_SECRET_EXPIRES_AT, clientSecretExpiresAt);
 		claims.put(OidcClientMetadataClaimNames.CLIENT_NAME, "client-name");
 		claims.put(OidcClientMetadataClaimNames.REDIRECT_URIS, Collections.singletonList("https://client.example.com"));
-		claims.put(OidcClientMetadataClaimNames.TOKEN_ENDPOINT_AUTH_METHOD, ClientAuthenticationMethod.BASIC.getValue());
+		claims.put(OidcClientMetadataClaimNames.TOKEN_ENDPOINT_AUTH_METHOD, ClientAuthenticationMethod.CLIENT_SECRET_BASIC.getValue());
 		claims.put(OidcClientMetadataClaimNames.GRANT_TYPES, Arrays.asList(
 				AuthorizationGrantType.AUTHORIZATION_CODE.getValue(), AuthorizationGrantType.CLIENT_CREDENTIALS.getValue()));
 		claims.put(OidcClientMetadataClaimNames.RESPONSE_TYPES, Collections.singletonList("code"));
@@ -114,7 +114,7 @@ public class OidcClientRegistrationTests {
 		assertThat(clientRegistration.getClientSecretExpiresAt()).isEqualTo(clientSecretExpiresAt);
 		assertThat(clientRegistration.getClientName()).isEqualTo("client-name");
 		assertThat(clientRegistration.getRedirectUris()).containsOnly("https://client.example.com");
-		assertThat(clientRegistration.getTokenEndpointAuthenticationMethod()).isEqualTo("basic");
+		assertThat(clientRegistration.getTokenEndpointAuthenticationMethod()).isEqualTo(ClientAuthenticationMethod.CLIENT_SECRET_BASIC.getValue());
 		assertThat(clientRegistration.getGrantTypes()).containsExactlyInAnyOrder("authorization_code", "client_credentials");
 		assertThat(clientRegistration.getResponseTypes()).containsOnly("code");
 		assertThat(clientRegistration.getScopes()).containsExactlyInAnyOrder("scope1", "scope2");

oauth2-authorization-server/src/test/java/org/springframework/security/oauth2/core/oidc/OidcProviderConfigurationTests.java

@@ -24,6 +24,8 @@ import java.util.Map;
 
 import org.junit.Test;
 
+import org.springframework.security.oauth2.core.ClientAuthenticationMethod;
+
 import static org.assertj.core.api.Assertions.assertThat;
 import static org.assertj.core.api.Assertions.assertThatIllegalArgumentException;
 
@@ -57,7 +59,7 @@ public class OidcProviderConfigurationTests {
 				.grantType("client_credentials")
 				.subjectType("public")
 				.idTokenSigningAlgorithm("RS256")
-				.tokenEndpointAuthenticationMethod("client_secret_basic")
+				.tokenEndpointAuthenticationMethod(ClientAuthenticationMethod.CLIENT_SECRET_BASIC.getValue())
 				.claim("a-claim", "a-value")
 				.build();
 
@@ -70,7 +72,7 @@ public class OidcProviderConfigurationTests {
 		assertThat(providerConfiguration.getGrantTypes()).containsExactlyInAnyOrder("authorization_code", "client_credentials");
 		assertThat(providerConfiguration.getSubjectTypes()).containsExactly("public");
 		assertThat(providerConfiguration.getIdTokenSigningAlgorithms()).containsExactly("RS256");
-		assertThat(providerConfiguration.getTokenEndpointAuthenticationMethods()).containsExactly("client_secret_basic");
+		assertThat(providerConfiguration.getTokenEndpointAuthenticationMethods()).containsExactly(ClientAuthenticationMethod.CLIENT_SECRET_BASIC.getValue());
 		assertThat(providerConfiguration.<String>getClaim("a-claim")).isEqualTo("a-value");
 	}
 

oauth2-authorization-server/src/test/java/org/springframework/security/oauth2/core/oidc/http/converter/OidcClientRegistrationHttpMessageConverterTests.java

@@ -97,7 +97,7 @@ public class OidcClientRegistrationHttpMessageConverterTests {
 				+"		\"redirect_uris\": [\n"
 				+ "			\"https://client.example.com\"\n"
 				+ "		],\n"
-				+"		\"token_endpoint_auth_method\": \"basic\",\n"
+				+"		\"token_endpoint_auth_method\": \"client_secret_basic\",\n"
 				+"		\"grant_types\": [\n"
 				+"			\"authorization_code\",\n"
 				+"			\"client_credentials\"\n"
@@ -121,7 +121,7 @@ public class OidcClientRegistrationHttpMessageConverterTests {
 		assertThat(clientRegistration.getClientSecretExpiresAt()).isEqualTo(Instant.ofEpochSecond(1607637467L));
 		assertThat(clientRegistration.getClientName()).isEqualTo("client-name");
 		assertThat(clientRegistration.getRedirectUris()).containsOnly("https://client.example.com");
-		assertThat(clientRegistration.getTokenEndpointAuthenticationMethod()).isEqualTo("basic");
+		assertThat(clientRegistration.getTokenEndpointAuthenticationMethod()).isEqualTo(ClientAuthenticationMethod.CLIENT_SECRET_BASIC.getValue());
 		assertThat(clientRegistration.getGrantTypes()).containsExactlyInAnyOrder("authorization_code", "client_credentials");
 		assertThat(clientRegistration.getResponseTypes()).containsOnly("code");
 		assertThat(clientRegistration.getScopes()).containsExactlyInAnyOrder("scope1", "scope2");
@@ -177,7 +177,7 @@ public class OidcClientRegistrationHttpMessageConverterTests {
 				.clientSecretExpiresAt(Instant.ofEpochSecond(1607637467))
 				.clientName("client-name")
 				.redirectUri("https://client.example.com")
-				.tokenEndpointAuthenticationMethod(ClientAuthenticationMethod.BASIC.getValue())
+				.tokenEndpointAuthenticationMethod(ClientAuthenticationMethod.CLIENT_SECRET_BASIC.getValue())
 				.grantType(AuthorizationGrantType.AUTHORIZATION_CODE.getValue())
 				.grantType(AuthorizationGrantType.CLIENT_CREDENTIALS.getValue())
 				.responseType(OAuth2AuthorizationResponseType.CODE.getValue())
@@ -198,7 +198,7 @@ public class OidcClientRegistrationHttpMessageConverterTests {
 		assertThat(clientRegistrationResponse).contains("\"client_secret_expires_at\":1607637467");
 		assertThat(clientRegistrationResponse).contains("\"client_name\":\"client-name\"");
 		assertThat(clientRegistrationResponse).contains("\"redirect_uris\":[\"https://client.example.com\"]");
-		assertThat(clientRegistrationResponse).contains("\"token_endpoint_auth_method\":\"basic\"");
+		assertThat(clientRegistrationResponse).contains("\"token_endpoint_auth_method\":\"client_secret_basic\"");
 		assertThat(clientRegistrationResponse).contains("\"grant_types\":[\"authorization_code\",\"client_credentials\"]");
 		assertThat(clientRegistrationResponse).contains("\"response_types\":[\"code\"]");
 		assertThat(clientRegistrationResponse).contains("\"scope\":\"scope1 scope2\"");

oauth2-authorization-server/src/test/java/org/springframework/security/oauth2/core/oidc/http/converter/OidcProviderConfigurationHttpMessageConverterTests.java

@@ -27,6 +27,7 @@ import org.springframework.http.converter.HttpMessageNotReadableException;
 import org.springframework.http.converter.HttpMessageNotWritableException;
 import org.springframework.mock.http.MockHttpOutputMessage;
 import org.springframework.mock.http.client.MockClientHttpResponse;
+import org.springframework.security.oauth2.core.ClientAuthenticationMethod;
 import org.springframework.security.oauth2.core.oidc.OidcProviderConfiguration;
 
 import static org.assertj.core.api.Assertions.assertThat;
@@ -116,7 +117,7 @@ public class OidcProviderConfigurationHttpMessageConverterTests {
 		assertThat(providerConfiguration.getGrantTypes()).containsExactlyInAnyOrder("authorization_code", "client_credentials");
 		assertThat(providerConfiguration.getSubjectTypes()).containsExactly("public");
 		assertThat(providerConfiguration.getIdTokenSigningAlgorithms()).containsExactly("RS256");
-		assertThat(providerConfiguration.getTokenEndpointAuthenticationMethods()).containsExactly("client_secret_basic");
+		assertThat(providerConfiguration.getTokenEndpointAuthenticationMethods()).containsExactly(ClientAuthenticationMethod.CLIENT_SECRET_BASIC.getValue());
 		assertThat(providerConfiguration.<String>getClaim("custom_claim")).isEqualTo("value");
 		assertThat(providerConfiguration.getClaimAsStringList("custom_collection_claim")).containsExactlyInAnyOrder("value1", "value2");
 	}
@@ -160,7 +161,7 @@ public class OidcProviderConfigurationHttpMessageConverterTests {
 						.grantType("client_credentials")
 						.subjectType("public")
 						.idTokenSigningAlgorithm("RS256")
-						.tokenEndpointAuthenticationMethod("client_secret_basic")
+						.tokenEndpointAuthenticationMethod(ClientAuthenticationMethod.CLIENT_SECRET_BASIC.getValue())
 						.claim("custom_claim", "value")
 						.claim("custom_collection_claim", Arrays.asList("value1", "value2"))
 						.build();

oauth2-authorization-server/src/test/java/org/springframework/security/oauth2/server/authorization/authentication/OAuth2ClientAuthenticationTokenTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2020 the original author or authors.
+ * Copyright 2020-2021 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -36,14 +36,14 @@ public class OAuth2ClientAuthenticationTokenTests {
 
 	@Test
 	public void constructorWhenClientIdNullThenThrowIllegalArgumentException() {
-		assertThatThrownBy(() -> new OAuth2ClientAuthenticationToken(null, "secret", ClientAuthenticationMethod.BASIC, null))
+		assertThatThrownBy(() -> new OAuth2ClientAuthenticationToken(null, "secret", ClientAuthenticationMethod.CLIENT_SECRET_BASIC, null))
 				.isInstanceOf(IllegalArgumentException.class)
 				.hasMessage("clientId cannot be empty");
 	}
 
 	@Test
 	public void constructorWhenClientSecretNullThenThrowIllegalArgumentException() {
-		assertThatThrownBy(() -> new OAuth2ClientAuthenticationToken("clientId", null, ClientAuthenticationMethod.BASIC, null))
+		assertThatThrownBy(() -> new OAuth2ClientAuthenticationToken("clientId", null, ClientAuthenticationMethod.CLIENT_SECRET_BASIC, null))
 				.isInstanceOf(IllegalArgumentException.class)
 				.hasMessage("clientSecret cannot be empty");
 	}
@@ -65,12 +65,12 @@ public class OAuth2ClientAuthenticationTokenTests {
 	@Test
 	public void constructorWhenClientCredentialsProvidedThenCreated() {
 		OAuth2ClientAuthenticationToken authentication = new OAuth2ClientAuthenticationToken("clientId", "secret",
-				ClientAuthenticationMethod.BASIC, null);
+				ClientAuthenticationMethod.CLIENT_SECRET_BASIC, null);
 		assertThat(authentication.isAuthenticated()).isFalse();
 		assertThat(authentication.getPrincipal().toString()).isEqualTo("clientId");
 		assertThat(authentication.getCredentials()).isEqualTo("secret");
 		assertThat(authentication.getRegisteredClient()).isNull();
-		assertThat(authentication.getClientAuthenticationMethod()).isEqualTo(ClientAuthenticationMethod.BASIC);
+		assertThat(authentication.getClientAuthenticationMethod()).isEqualTo(ClientAuthenticationMethod.CLIENT_SECRET_BASIC);
 	}
 
 	@Test

oauth2-authorization-server/src/test/java/org/springframework/security/oauth2/server/authorization/authentication/OAuth2ClientCredentialsAuthenticationProviderTests.java

@@ -122,7 +122,7 @@ public class OAuth2ClientCredentialsAuthenticationProviderTests {
 	public void authenticateWhenClientPrincipalNotAuthenticatedThenThrowOAuth2AuthenticationException() {
 		RegisteredClient registeredClient = TestRegisteredClients.registeredClient2().build();
 		OAuth2ClientAuthenticationToken clientPrincipal = new OAuth2ClientAuthenticationToken(
-				registeredClient.getClientId(), registeredClient.getClientSecret(), ClientAuthenticationMethod.BASIC, null);
+				registeredClient.getClientId(), registeredClient.getClientSecret(), ClientAuthenticationMethod.CLIENT_SECRET_BASIC, null);
 		OAuth2ClientCredentialsAuthenticationToken authentication =
 				new OAuth2ClientCredentialsAuthenticationToken(clientPrincipal, null, null);
 

oauth2-authorization-server/src/test/java/org/springframework/security/oauth2/server/authorization/authentication/OAuth2RefreshTokenAuthenticationProviderTests.java

@@ -337,7 +337,7 @@ public class OAuth2RefreshTokenAuthenticationProviderTests {
 	public void authenticateWhenClientPrincipalNotAuthenticatedThenThrowOAuth2AuthenticationException() {
 		RegisteredClient registeredClient = TestRegisteredClients.registeredClient().build();
 		OAuth2ClientAuthenticationToken clientPrincipal = new OAuth2ClientAuthenticationToken(
-				registeredClient.getClientId(), registeredClient.getClientSecret(), ClientAuthenticationMethod.BASIC, null);
+				registeredClient.getClientId(), registeredClient.getClientSecret(), ClientAuthenticationMethod.CLIENT_SECRET_BASIC, null);
 		OAuth2RefreshTokenAuthenticationToken authentication = new OAuth2RefreshTokenAuthenticationToken(
 				"refresh-token", clientPrincipal, null, null);
 

oauth2-authorization-server/src/test/java/org/springframework/security/oauth2/server/authorization/authentication/OAuth2TokenIntrospectionAuthenticationProviderTests.java

@@ -107,7 +107,7 @@ public class OAuth2TokenIntrospectionAuthenticationProviderTests {
 	public void authenticateWhenClientPrincipalNotAuthenticatedThenThrowOAuth2AuthenticationException() {
 		RegisteredClient registeredClient = TestRegisteredClients.registeredClient().build();
 		OAuth2ClientAuthenticationToken clientPrincipal = new OAuth2ClientAuthenticationToken(
-				registeredClient.getClientId(), registeredClient.getClientSecret(), ClientAuthenticationMethod.BASIC, null);
+				registeredClient.getClientId(), registeredClient.getClientSecret(), ClientAuthenticationMethod.CLIENT_SECRET_BASIC, null);
 
 		OAuth2TokenIntrospectionAuthenticationToken authentication = new OAuth2TokenIntrospectionAuthenticationToken(
 				"token", clientPrincipal, null, null);

oauth2-authorization-server/src/test/java/org/springframework/security/oauth2/server/authorization/authentication/OAuth2TokenRevocationAuthenticationProviderTests.java

@@ -88,7 +88,7 @@ public class OAuth2TokenRevocationAuthenticationProviderTests {
 	public void authenticateWhenClientPrincipalNotAuthenticatedThenThrowOAuth2AuthenticationException() {
 		RegisteredClient registeredClient = TestRegisteredClients.registeredClient().build();
 		OAuth2ClientAuthenticationToken clientPrincipal = new OAuth2ClientAuthenticationToken(
-				registeredClient.getClientId(), registeredClient.getClientSecret(), ClientAuthenticationMethod.BASIC, null);
+				registeredClient.getClientId(), registeredClient.getClientSecret(), ClientAuthenticationMethod.CLIENT_SECRET_BASIC, null);
 		OAuth2TokenRevocationAuthenticationToken authentication = new OAuth2TokenRevocationAuthenticationToken(
 				"token", clientPrincipal, OAuth2TokenType.ACCESS_TOKEN.getValue());
 		assertThatThrownBy(() -> this.authenticationProvider.authenticate(authentication))

oauth2-authorization-server/src/test/java/org/springframework/security/oauth2/server/authorization/client/InMemoryRegisteredClientRepositoryTests.java

@@ -205,7 +205,7 @@ public class InMemoryRegisteredClientRepositoryTests {
 				.clientId(clientId)
 				.clientSecret(clientSecret)
 				.authorizationGrantType(AuthorizationGrantType.CLIENT_CREDENTIALS)
-				.clientAuthenticationMethod(ClientAuthenticationMethod.BASIC)
+				.clientAuthenticationMethod(ClientAuthenticationMethod.CLIENT_SECRET_BASIC)
 				.redirectUri("https://client.example.com")
 				.scope("scope1")
 				.build();

oauth2-authorization-server/src/test/java/org/springframework/security/oauth2/server/authorization/client/RegisteredClientTests.java

@@ -53,7 +53,7 @@ public class RegisteredClientTests {
 						.clientSecret(CLIENT_SECRET)
 						.redirectUris(redirectUris -> redirectUris.addAll(REDIRECT_URIS))
 						.scopes(scopes -> scopes.addAll(SCOPES))
-						.clientAuthenticationMethod(ClientAuthenticationMethod.BASIC)
+						.clientAuthenticationMethod(ClientAuthenticationMethod.CLIENT_SECRET_BASIC)
 						.build()
 		).isInstanceOf(IllegalArgumentException.class);
 	}
@@ -69,7 +69,7 @@ public class RegisteredClientTests {
 				.clientSecretExpiresAt(clientSecretExpiresAt)
 				.clientName("client-name")
 				.authorizationGrantType(AuthorizationGrantType.AUTHORIZATION_CODE)
-				.clientAuthenticationMethod(ClientAuthenticationMethod.BASIC)
+				.clientAuthenticationMethod(ClientAuthenticationMethod.CLIENT_SECRET_BASIC)
 				.redirectUris(redirectUris -> redirectUris.addAll(REDIRECT_URIS))
 				.scopes(scopes -> scopes.addAll(SCOPES))
 				.build();
@@ -100,7 +100,7 @@ public class RegisteredClientTests {
 						.clientId(null)
 						.clientSecret(CLIENT_SECRET)
 						.authorizationGrantType(AuthorizationGrantType.AUTHORIZATION_CODE)
-						.clientAuthenticationMethod(ClientAuthenticationMethod.BASIC)
+						.clientAuthenticationMethod(ClientAuthenticationMethod.CLIENT_SECRET_BASIC)
 						.redirectUris(redirectUris -> redirectUris.addAll(REDIRECT_URIS))
 						.scopes(scopes -> scopes.addAll(SCOPES))
 						.build()
@@ -114,7 +114,7 @@ public class RegisteredClientTests {
 						.clientId(CLIENT_ID)
 						.clientSecret(CLIENT_SECRET)
 						.authorizationGrantType(AuthorizationGrantType.AUTHORIZATION_CODE)
-						.clientAuthenticationMethod(ClientAuthenticationMethod.BASIC)
+						.clientAuthenticationMethod(ClientAuthenticationMethod.CLIENT_SECRET_BASIC)
 						.scopes(scopes -> scopes.addAll(SCOPES))
 						.build()
 		).isInstanceOf(IllegalArgumentException.class);
@@ -127,7 +127,7 @@ public class RegisteredClientTests {
 						.clientId(CLIENT_ID)
 						.clientSecret(CLIENT_SECRET)
 						.authorizationGrantType(AuthorizationGrantType.AUTHORIZATION_CODE)
-						.clientAuthenticationMethod(ClientAuthenticationMethod.BASIC)
+						.clientAuthenticationMethod(ClientAuthenticationMethod.CLIENT_SECRET_BASIC)
 						.redirectUri("https://example.com")
 						.redirectUris(Set::clear)
 						.scopes(scopes -> scopes.addAll(SCOPES))
@@ -155,7 +155,7 @@ public class RegisteredClientTests {
 				.clientId(CLIENT_ID)
 				.clientSecret(CLIENT_SECRET)
 				.authorizationGrantType(AuthorizationGrantType.AUTHORIZATION_CODE)
-				.clientAuthenticationMethod(ClientAuthenticationMethod.BASIC)
+				.clientAuthenticationMethod(ClientAuthenticationMethod.CLIENT_SECRET_BASIC)
 				.redirectUris(redirectUris -> redirectUris.addAll(REDIRECT_URIS))
 				.build();
 	}
@@ -166,7 +166,7 @@ public class RegisteredClientTests {
 				.clientId(CLIENT_ID)
 				.clientSecret(CLIENT_SECRET)
 				.authorizationGrantType(AuthorizationGrantType.AUTHORIZATION_CODE)
-				.clientAuthenticationMethod(ClientAuthenticationMethod.BASIC)
+				.clientAuthenticationMethod(ClientAuthenticationMethod.CLIENT_SECRET_BASIC)
 				.redirectUris(redirectUris -> redirectUris.addAll(REDIRECT_URIS))
 				.scopes(scopes -> scopes.addAll(SCOPES))
 				.build();
@@ -180,7 +180,7 @@ public class RegisteredClientTests {
 				RegisteredClient.withId(ID)
 						.clientId(CLIENT_ID)
 						.authorizationGrantType(AuthorizationGrantType.AUTHORIZATION_CODE)
-						.clientAuthenticationMethod(ClientAuthenticationMethod.BASIC)
+						.clientAuthenticationMethod(ClientAuthenticationMethod.CLIENT_SECRET_BASIC)
 						.redirectUris(redirectUris -> redirectUris.addAll(REDIRECT_URIS))
 						.scope("openid profile")
 						.build()
@@ -194,7 +194,7 @@ public class RegisteredClientTests {
 						.clientId(CLIENT_ID)
 						.clientSecret(CLIENT_SECRET)
 						.authorizationGrantType(AuthorizationGrantType.AUTHORIZATION_CODE)
-						.clientAuthenticationMethod(ClientAuthenticationMethod.BASIC)
+						.clientAuthenticationMethod(ClientAuthenticationMethod.CLIENT_SECRET_BASIC)
 						.redirectUris(redirectUris -> redirectUris.addAll(REDIRECT_URIS))
 						.scope("an\"invalid\"scope")
 						.build()
@@ -208,7 +208,7 @@ public class RegisteredClientTests {
 						.clientId(CLIENT_ID)
 						.clientSecret(CLIENT_SECRET)
 						.authorizationGrantType(AuthorizationGrantType.AUTHORIZATION_CODE)
-						.clientAuthenticationMethod(ClientAuthenticationMethod.BASIC)
+						.clientAuthenticationMethod(ClientAuthenticationMethod.CLIENT_SECRET_BASIC)
 						.redirectUri("invalid URI")
 						.scopes(scopes -> scopes.addAll(SCOPES))
 						.build()
@@ -222,7 +222,7 @@ public class RegisteredClientTests {
 						.clientId(CLIENT_ID)
 						.clientSecret(CLIENT_SECRET)
 						.authorizationGrantType(AuthorizationGrantType.AUTHORIZATION_CODE)
-						.clientAuthenticationMethod(ClientAuthenticationMethod.BASIC)
+						.clientAuthenticationMethod(ClientAuthenticationMethod.CLIENT_SECRET_BASIC)
 						.redirectUri("https://example.com/page#fragment")
 						.scopes(scopes -> scopes.addAll(SCOPES))
 						.build()
@@ -236,7 +236,7 @@ public class RegisteredClientTests {
 				.clientSecret(CLIENT_SECRET)
 				.authorizationGrantType(AuthorizationGrantType.AUTHORIZATION_CODE)
 				.authorizationGrantType(AuthorizationGrantType.CLIENT_CREDENTIALS)
-				.clientAuthenticationMethod(ClientAuthenticationMethod.BASIC)
+				.clientAuthenticationMethod(ClientAuthenticationMethod.CLIENT_SECRET_BASIC)
 				.redirectUris(redirectUris -> redirectUris.addAll(REDIRECT_URIS))
 				.scopes(scopes -> scopes.addAll(SCOPES))
 				.build();
@@ -254,7 +254,7 @@ public class RegisteredClientTests {
 					authorizationGrantTypes.add(AuthorizationGrantType.AUTHORIZATION_CODE);
 					authorizationGrantTypes.add(AuthorizationGrantType.CLIENT_CREDENTIALS);
 				})
-				.clientAuthenticationMethod(ClientAuthenticationMethod.BASIC)
+				.clientAuthenticationMethod(ClientAuthenticationMethod.CLIENT_SECRET_BASIC)
 				.redirectUris(redirectUris -> redirectUris.addAll(REDIRECT_URIS))
 				.scopes(scopes -> scopes.addAll(SCOPES))
 				.build();
@@ -271,7 +271,7 @@ public class RegisteredClientTests {
 					.clientSecret(CLIENT_SECRET)
 					.authorizationGrantType(AuthorizationGrantType.AUTHORIZATION_CODE)
 					.authorizationGrantTypes(Set::clear)
-					.clientAuthenticationMethod(ClientAuthenticationMethod.BASIC)
+					.clientAuthenticationMethod(ClientAuthenticationMethod.CLIENT_SECRET_BASIC)
 					.redirectUris(redirectUris -> redirectUris.addAll(REDIRECT_URIS))
 					.scopes(scopes -> scopes.addAll(SCOPES))
 					.build();
@@ -294,22 +294,6 @@ public class RegisteredClientTests {
 				.containsExactlyInAnyOrder(ClientAuthenticationMethod.CLIENT_SECRET_BASIC, ClientAuthenticationMethod.CLIENT_SECRET_POST);
 	}
 
-	@Test
-	public void buildWhenBothDeprecatedClientAuthenticationMethodsAreProvidedThenBothNonDeprecatedAreRegistered() {
-		RegisteredClient registration = RegisteredClient.withId(ID)
-				.clientId(CLIENT_ID)
-				.clientSecret(CLIENT_SECRET)
-				.authorizationGrantType(AuthorizationGrantType.AUTHORIZATION_CODE)
-				.clientAuthenticationMethod(ClientAuthenticationMethod.BASIC)
-				.clientAuthenticationMethod(ClientAuthenticationMethod.POST)
-				.redirectUris(redirectUris -> redirectUris.addAll(REDIRECT_URIS))
-				.scopes(scopes -> scopes.addAll(SCOPES))
-				.build();
-
-		assertThat(registration.getClientAuthenticationMethods())
-				.containsExactlyInAnyOrder(ClientAuthenticationMethod.CLIENT_SECRET_BASIC, ClientAuthenticationMethod.CLIENT_SECRET_POST);
-	}
-
 	@Test
 	public void buildWhenClientAuthenticationMethodsConsumerIsProvidedThenConsumerAccepted() {
 		RegisteredClient registration = RegisteredClient.withId(ID)
@@ -328,24 +312,6 @@ public class RegisteredClientTests {
 				.containsExactlyInAnyOrder(ClientAuthenticationMethod.CLIENT_SECRET_BASIC, ClientAuthenticationMethod.CLIENT_SECRET_POST);
 	}
 
-	@Test
-	public void buildWhenConsumerAddsDeprecatedClientAuthenticationMethodsThenNonDeprecatedAreRegistered() {
-		RegisteredClient registration = RegisteredClient.withId(ID)
-				.clientId(CLIENT_ID)
-				.clientSecret(CLIENT_SECRET)
-				.authorizationGrantType(AuthorizationGrantType.AUTHORIZATION_CODE)
-				.clientAuthenticationMethods(clientAuthenticationMethods -> {
-					clientAuthenticationMethods.add(ClientAuthenticationMethod.BASIC);
-					clientAuthenticationMethods.add(ClientAuthenticationMethod.POST);
-				})
-				.redirectUris(redirectUris -> redirectUris.addAll(REDIRECT_URIS))
-				.scopes(scopes -> scopes.addAll(SCOPES))
-				.build();
-
-		assertThat(registration.getClientAuthenticationMethods())
-				.containsExactlyInAnyOrder(ClientAuthenticationMethod.CLIENT_SECRET_BASIC, ClientAuthenticationMethod.CLIENT_SECRET_POST);
-	}
-
 	@Test
 	public void buildWhenOverrideIdThenOverridden() {
 		String overriddenId = "override";
@@ -354,7 +320,7 @@ public class RegisteredClientTests {
 				.clientId(CLIENT_ID)
 				.clientSecret(CLIENT_SECRET)
 				.authorizationGrantType(AuthorizationGrantType.AUTHORIZATION_CODE)
-				.clientAuthenticationMethod(ClientAuthenticationMethod.BASIC)
+				.clientAuthenticationMethod(ClientAuthenticationMethod.CLIENT_SECRET_BASIC)
 				.redirectUris(redirectUris -> redirectUris.addAll(REDIRECT_URIS))
 				.scopes(scopes -> scopes.addAll(SCOPES))
 				.build();

oauth2-authorization-server/src/test/java/org/springframework/security/oauth2/server/authorization/oidc/web/OidcClientRegistrationEndpointFilterTests.java

@@ -216,7 +216,7 @@ public class OidcClientRegistrationEndpointFilterTests {
 				.clientId("client-id")
 				.clientIdIssuedAt(Instant.now())
 				.clientSecret("client-secret")
-				.tokenEndpointAuthenticationMethod(ClientAuthenticationMethod.BASIC.getValue())
+				.tokenEndpointAuthenticationMethod(ClientAuthenticationMethod.CLIENT_SECRET_BASIC.getValue())
 				.responseType(OAuth2AuthorizationResponseType.CODE.getValue())
 				.idTokenSignedResponseAlgorithm(SignatureAlgorithm.RS256.getName())
 				.build();

oauth2-authorization-server/src/test/java/org/springframework/security/oauth2/server/authorization/web/OAuth2ClientAuthenticationFilterTests.java

@@ -167,7 +167,7 @@ public class OAuth2ClientAuthenticationFilterTests {
 	@Test
 	public void doFilterWhenRequestMatchesAndBadCredentialsThenInvalidClientError() throws Exception {
 		when(this.authenticationConverter.convert(any(HttpServletRequest.class))).thenReturn(
-				new OAuth2ClientAuthenticationToken("clientId", "invalid-secret", ClientAuthenticationMethod.BASIC, null));
+				new OAuth2ClientAuthenticationToken("clientId", "invalid-secret", ClientAuthenticationMethod.CLIENT_SECRET_BASIC, null));
 		when(this.authenticationManager.authenticate(any(Authentication.class))).thenThrow(
 				new OAuth2AuthenticationException(new OAuth2Error(OAuth2ErrorCodes.INVALID_CLIENT)));
 
@@ -192,7 +192,7 @@ public class OAuth2ClientAuthenticationFilterTests {
 
 		RegisteredClient registeredClient = TestRegisteredClients.registeredClient().build();
 		when(this.authenticationConverter.convert(any(HttpServletRequest.class))).thenReturn(
-				new OAuth2ClientAuthenticationToken(registeredClient.getClientId(), registeredClient.getClientSecret(), ClientAuthenticationMethod.BASIC, null));
+				new OAuth2ClientAuthenticationToken(registeredClient.getClientId(), registeredClient.getClientSecret(), ClientAuthenticationMethod.CLIENT_SECRET_BASIC, null));
 		when(this.authenticationManager.authenticate(any(Authentication.class))).thenReturn(
 				new OAuth2ClientAuthenticationToken(registeredClient));
 

samples/boot/oauth2-integration/authorizationserver-custom-consent-page/src/main/java/sample/config/AuthorizationServerConfig.java

@@ -77,7 +77,7 @@ public class AuthorizationServerConfig {
 		RegisteredClient registeredClient = RegisteredClient.withId(UUID.randomUUID().toString())
 				.clientId("messaging-client")
 				.clientSecret("{noop}secret")
-				.clientAuthenticationMethod(ClientAuthenticationMethod.BASIC)
+				.clientAuthenticationMethod(ClientAuthenticationMethod.CLIENT_SECRET_BASIC)
 				.authorizationGrantType(AuthorizationGrantType.AUTHORIZATION_CODE)
 				.authorizationGrantType(AuthorizationGrantType.REFRESH_TOKEN)
 				.authorizationGrantType(AuthorizationGrantType.CLIENT_CREDENTIALS)

samples/boot/oauth2-integration/authorizationserver/src/main/java/sample/config/AuthorizationServerConfig.java

@@ -68,7 +68,7 @@ public class AuthorizationServerConfig {
 		RegisteredClient registeredClient = RegisteredClient.withId(UUID.randomUUID().toString())
 				.clientId("messaging-client")
 				.clientSecret("{noop}secret")
-				.clientAuthenticationMethod(ClientAuthenticationMethod.BASIC)
+				.clientAuthenticationMethod(ClientAuthenticationMethod.CLIENT_SECRET_BASIC)
 				.authorizationGrantType(AuthorizationGrantType.AUTHORIZATION_CODE)
 				.authorizationGrantType(AuthorizationGrantType.REFRESH_TOKEN)
 				.authorizationGrantType(AuthorizationGrantType.CLIENT_CREDENTIALS)