Return PAR endpoint metadata only when enabled

Issue https://github.com/spring-projects/spring-authorization-server/issues/2219

config/src/main/java/org/springframework/security/config/annotation/web/configurers/oauth2/server/authorization/OAuth2AuthorizationServerConfigurer.java

@@ -482,6 +482,27 @@ public final class OAuth2AuthorizationServerConfigurer
 			});
 		}
 
+		OAuth2PushedAuthorizationRequestEndpointConfigurer pushedAuthorizationRequestEndpointConfigurer = getConfigurer(
+				OAuth2PushedAuthorizationRequestEndpointConfigurer.class);
+		if (pushedAuthorizationRequestEndpointConfigurer != null) {
+			OAuth2AuthorizationServerMetadataEndpointConfigurer authorizationServerMetadataEndpointConfigurer = getConfigurer(
+					OAuth2AuthorizationServerMetadataEndpointConfigurer.class);
+
+			authorizationServerMetadataEndpointConfigurer.addDefaultAuthorizationServerMetadataCustomizer((builder) -> {
+				AuthorizationServerContext authorizationServerContext = AuthorizationServerContextHolder.getContext();
+				String issuer = authorizationServerContext.getIssuer();
+				AuthorizationServerSettings authorizationServerSettings = authorizationServerContext
+					.getAuthorizationServerSettings();
+
+				String pushedAuthorizationRequestEndpoint = UriComponentsBuilder.fromUriString(issuer)
+					.path(authorizationServerSettings.getPushedAuthorizationRequestEndpoint())
+					.build()
+					.toUriString();
+
+				builder.pushedAuthorizationRequestEndpoint(pushedAuthorizationRequestEndpoint);
+			});
+		}
+
 		this.configurers.values().forEach((configurer) -> configurer.configure(httpSecurity));
 
 		AuthorizationServerSettings authorizationServerSettings = OAuth2ConfigurerUtils

config/src/main/java/org/springframework/security/config/annotation/web/configurers/oauth2/server/authorization/OidcConfigurer.java

@@ -171,6 +171,28 @@ public final class OidcConfigurer extends AbstractOAuth2Configurer {
 			});
 		}
 
+		OAuth2PushedAuthorizationRequestEndpointConfigurer pushedAuthorizationRequestEndpointConfigurer = httpSecurity
+			.getConfigurer(OAuth2AuthorizationServerConfigurer.class)
+			.getConfigurer(OAuth2PushedAuthorizationRequestEndpointConfigurer.class);
+		if (pushedAuthorizationRequestEndpointConfigurer != null) {
+			OidcProviderConfigurationEndpointConfigurer providerConfigurationEndpointConfigurer = getConfigurer(
+					OidcProviderConfigurationEndpointConfigurer.class);
+
+			providerConfigurationEndpointConfigurer.addDefaultProviderConfigurationCustomizer((builder) -> {
+				AuthorizationServerContext authorizationServerContext = AuthorizationServerContextHolder.getContext();
+				String issuer = authorizationServerContext.getIssuer();
+				AuthorizationServerSettings authorizationServerSettings = authorizationServerContext
+					.getAuthorizationServerSettings();
+
+				String pushedAuthorizationRequestEndpoint = UriComponentsBuilder.fromUriString(issuer)
+					.path(authorizationServerSettings.getPushedAuthorizationRequestEndpoint())
+					.build()
+					.toUriString();
+
+				builder.pushedAuthorizationRequestEndpoint(pushedAuthorizationRequestEndpoint);
+			});
+		}
+
 		this.configurers.values().forEach((configurer) -> configurer.configure(httpSecurity));
 	}
 

config/src/test/java/org/springframework/security/config/annotation/web/configurers/oauth2/server/authorization/OAuth2AuthorizationServerMetadataTests.java

@@ -185,6 +185,17 @@ public class OAuth2AuthorizationServerMetadataTests {
 			.andExpect(jsonPath("$.grant_types_supported[4]").value(AuthorizationGrantType.DEVICE_CODE.getValue()));
 	}
 
+	@Test
+	public void requestWhenAuthorizationServerMetadataRequestAndPushedAuthorizationRequestEnabledThenMetadataResponseIncludesPushedAuthorizationRequestEndpoint()
+			throws Exception {
+		this.spring.register(AuthorizationServerConfigurationWithPushedAuthorizationRequestEnabled.class).autowire();
+
+		this.mvc.perform(get(ISSUER.concat(DEFAULT_OAUTH2_AUTHORIZATION_SERVER_METADATA_ENDPOINT_URI)))
+			.andExpect(status().is2xxSuccessful())
+			.andExpect(jsonPath("$.pushed_authorization_request_endpoint")
+				.value(ISSUER.concat(this.authorizationServerSettings.getPushedAuthorizationRequestEndpoint())));
+	}
+
 	@EnableWebSecurity
 	@Import(OAuth2AuthorizationServerConfiguration.class)
 	static class AuthorizationServerConfiguration {
@@ -301,4 +312,26 @@ public class OAuth2AuthorizationServerMetadataTests {
 
 	}
 
+	@EnableWebSecurity
+	@Configuration(proxyBeanMethods = false)
+	static class AuthorizationServerConfigurationWithPushedAuthorizationRequestEnabled
+			extends AuthorizationServerConfiguration {
+
+		// @formatter:off
+		@Bean
+		SecurityFilterChain authorizationServerSecurityFilterChain(HttpSecurity http) throws Exception {
+			http
+					.oauth2AuthorizationServer((authorizationServer) ->
+							authorizationServer
+									.pushedAuthorizationRequestEndpoint(Customizer.withDefaults())
+					)
+					.authorizeHttpRequests((authorize) ->
+							authorize.anyRequest().authenticated()
+					);
+			return http.build();
+		}
+		// @formatter:on
+
+	}
+
 }

config/src/test/java/org/springframework/security/config/annotation/web/configurers/oauth2/server/authorization/OidcProviderConfigurationTests.java

@@ -159,6 +159,18 @@ public class OidcProviderConfigurationTests {
 			.andExpect(jsonPath("$.grant_types_supported[4]").value(AuthorizationGrantType.DEVICE_CODE.getValue()));
 	}
 
+	@Test
+	public void requestWhenConfigurationRequestAndPushedAuthorizationRequestEnabledThenConfigurationResponseIncludesPushedAuthorizationRequestEndpoint()
+			throws Exception {
+		this.spring.register(AuthorizationServerConfigurationWithPushedAuthorizationRequestEnabled.class).autowire();
+
+		this.mvc.perform(get(ISSUER.concat(DEFAULT_OIDC_PROVIDER_CONFIGURATION_ENDPOINT_URI)))
+			.andExpect(status().is2xxSuccessful())
+			.andExpectAll(defaultConfigurationMatchers(ISSUER))
+			.andExpect(jsonPath("$.pushed_authorization_request_endpoint")
+				.value(ISSUER.concat(this.authorizationServerSettings.getPushedAuthorizationRequestEndpoint())));
+	}
+
 	private ResultMatcher[] defaultConfigurationMatchers(String issuer) {
 		// @formatter:off
 		return new ResultMatcher[] {
@@ -357,6 +369,26 @@ public class OidcProviderConfigurationTests {
 
 	}
 
+	@EnableWebSecurity
+	@Configuration(proxyBeanMethods = false)
+	static class AuthorizationServerConfigurationWithPushedAuthorizationRequestEnabled
+			extends AuthorizationServerConfiguration {
+
+		// @formatter:off
+		@Bean
+		SecurityFilterChain authorizationServerSecurityFilterChain(HttpSecurity http) throws Exception {
+			http
+					.oauth2AuthorizationServer((authorizationServer) ->
+							authorizationServer
+									.pushedAuthorizationRequestEndpoint(Customizer.withDefaults())
+									.oidc(Customizer.withDefaults())
+					);
+			return http.build();
+		}
+		// @formatter:on
+
+	}
+
 	@EnableWebSecurity
 	@Configuration(proxyBeanMethods = false)
 	static class AuthorizationServerConfigurationWithInvalidIssuerUrl extends AuthorizationServerConfiguration {

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

@@ -101,8 +101,6 @@ public final class OidcProviderConfigurationEndpointFilter extends OncePerReques
 		OidcProviderConfiguration.Builder providerConfiguration = OidcProviderConfiguration.builder()
 			.issuer(issuer)
 			.authorizationEndpoint(asUrl(issuer, authorizationServerSettings.getAuthorizationEndpoint()))
-			.pushedAuthorizationRequestEndpoint(
-					asUrl(issuer, authorizationServerSettings.getPushedAuthorizationRequestEndpoint()))
 			.tokenEndpoint(asUrl(issuer, authorizationServerSettings.getTokenEndpoint()))
 			.tokenEndpointAuthenticationMethods(clientAuthenticationMethods())
 			.jwkSetUrl(asUrl(issuer, authorizationServerSettings.getJwkSetEndpoint()))

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

@@ -101,8 +101,6 @@ public final class OAuth2AuthorizationServerMetadataEndpointFilter extends OnceP
 			.builder()
 			.issuer(issuer)
 			.authorizationEndpoint(asUrl(issuer, authorizationServerSettings.getAuthorizationEndpoint()))
-			.pushedAuthorizationRequestEndpoint(
-					asUrl(issuer, authorizationServerSettings.getPushedAuthorizationRequestEndpoint()))
 			.tokenEndpoint(asUrl(issuer, authorizationServerSettings.getTokenEndpoint()))
 			.tokenEndpointAuthenticationMethods(clientAuthenticationMethods())
 			.jwkSetUrl(asUrl(issuer, authorizationServerSettings.getJwkSetEndpoint()))

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

@@ -134,8 +134,7 @@ public class OidcProviderConfigurationEndpointFilterTests {
 		assertThat(providerConfigurationResponse).contains("\"issuer\":\"https://example.com\"");
 		assertThat(providerConfigurationResponse)
 			.contains("\"authorization_endpoint\":\"https://example.com/oauth2/v1/authorize\"");
-		assertThat(providerConfigurationResponse)
+		assertThat(providerConfigurationResponse).doesNotContain("\"pushed_authorization_request_endpoint\"");
-			.contains("\"pushed_authorization_request_endpoint\":\"https://example.com/oauth2/v1/par\"");
 		assertThat(providerConfigurationResponse).doesNotContain("\"device_authorization_endpoint\"");
 		assertThat(providerConfigurationResponse)
 			.contains("\"token_endpoint\":\"https://example.com/oauth2/v1/token\"");

oauth2/oauth2-authorization-server/src/test/java/org/springframework/security/oauth2/server/authorization/web/OAuth2AuthorizationServerMetadataEndpointFilterTests.java

@@ -130,8 +130,7 @@ public class OAuth2AuthorizationServerMetadataEndpointFilterTests {
 		assertThat(authorizationServerMetadataResponse).contains("\"issuer\":\"https://example.com\"");
 		assertThat(authorizationServerMetadataResponse)
 			.contains("\"authorization_endpoint\":\"https://example.com/oauth2/v1/authorize\"");
-		assertThat(authorizationServerMetadataResponse)
+		assertThat(authorizationServerMetadataResponse).doesNotContain("\"pushed_authorization_request_endpoint\"");
-			.contains("\"pushed_authorization_request_endpoint\":\"https://example.com/oauth2/v1/par\"");
 		assertThat(authorizationServerMetadataResponse).doesNotContain("\"device_authorization_endpoint\"");
 		assertThat(authorizationServerMetadataResponse)
 			.contains("\"token_endpoint\":\"https://example.com/oauth2/v1/token\"");