Add OAuth2AuthorizationServerConfigurer

Closes gh-85

config/spring-authorization-server-config.gradle

@@ -1 +1,14 @@
 apply plugin: 'io.spring.convention.spring-module'
+
+dependencies {
+	compile 'org.springframework.security:spring-security-core'
+	compile 'org.springframework.security:spring-security-config'
+	compile springCoreDependency
+	compile project(':spring-authorization-server-core')
+
+	testCompile 'junit:junit'
+	testCompile 'org.assertj:assertj-core'
+	testCompile 'org.mockito:mockito-core'
+
+	provided 'javax.servlet:javax.servlet-api'
+}

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

@@ -0,0 +1,152 @@
+/*
+ * Copyright 2020 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.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.springframework.security.config.annotation.web.configurers.oauth2.server.authorization;
+
+import org.springframework.beans.factory.BeanFactoryUtils;
+import org.springframework.beans.factory.NoUniqueBeanDefinitionException;
+import org.springframework.context.ApplicationContext;
+import org.springframework.http.HttpMethod;
+import org.springframework.security.authentication.AuthenticationManager;
+import org.springframework.security.config.annotation.web.HttpSecurityBuilder;
+import org.springframework.security.config.annotation.web.configurers.AbstractHttpConfigurer;
+import org.springframework.security.oauth2.server.authorization.InMemoryOAuth2AuthorizationService;
+import org.springframework.security.oauth2.server.authorization.OAuth2AuthorizationService;
+import org.springframework.security.oauth2.server.authorization.authentication.OAuth2AuthorizationCodeAuthenticationProvider;
+import org.springframework.security.oauth2.server.authorization.authentication.OAuth2ClientAuthenticationProvider;
+import org.springframework.security.oauth2.server.authorization.client.RegisteredClientRepository;
+import org.springframework.security.oauth2.server.authorization.web.OAuth2AuthorizationEndpointFilter;
+import org.springframework.security.oauth2.server.authorization.web.OAuth2ClientAuthenticationFilter;
+import org.springframework.security.oauth2.server.authorization.web.OAuth2TokenEndpointFilter;
+import org.springframework.security.web.access.intercept.FilterSecurityInterceptor;
+import org.springframework.security.web.authentication.preauth.AbstractPreAuthenticatedProcessingFilter;
+import org.springframework.security.web.util.matcher.AntPathRequestMatcher;
+import org.springframework.util.Assert;
+import org.springframework.util.StringUtils;
+
+import java.util.Map;
+
+/**
+ * An {@link AbstractHttpConfigurer} for OAuth 2.0 Authorization Server support.
+ *
+ * @author Joe Grandja
+ * @since 0.0.1
+ * @see AbstractHttpConfigurer
+ * @see RegisteredClientRepository
+ * @see OAuth2AuthorizationService
+ * @see OAuth2AuthorizationEndpointFilter
+ * @see OAuth2TokenEndpointFilter
+ * @see OAuth2ClientAuthenticationFilter
+ */
+public final class OAuth2AuthorizationServerConfigurer<B extends HttpSecurityBuilder<B>>
+		extends AbstractHttpConfigurer<OAuth2AuthorizationServerConfigurer<B>, B> {
+
+	/**
+	 * Sets the repository of registered clients.
+	 *
+	 * @param registeredClientRepository the repository of registered clients
+	 * @return the {@link OAuth2AuthorizationServerConfigurer} for further configuration
+	 */
+	public OAuth2AuthorizationServerConfigurer<B> registeredClientRepository(RegisteredClientRepository registeredClientRepository) {
+		Assert.notNull(registeredClientRepository, "registeredClientRepository cannot be null");
+		this.getBuilder().setSharedObject(RegisteredClientRepository.class, registeredClientRepository);
+		return this;
+	}
+
+	/**
+	 * Sets the authorization service.
+	 *
+	 * @param authorizationService the authorization service
+	 * @return the {@link OAuth2AuthorizationServerConfigurer} for further configuration
+	 */
+	public OAuth2AuthorizationServerConfigurer<B> authorizationService(OAuth2AuthorizationService authorizationService) {
+		Assert.notNull(authorizationService, "authorizationService cannot be null");
+		this.getBuilder().setSharedObject(OAuth2AuthorizationService.class, authorizationService);
+		return this;
+	}
+
+	@Override
+	public void init(B builder) {
+		OAuth2ClientAuthenticationProvider clientAuthenticationProvider =
+				new OAuth2ClientAuthenticationProvider(
+						getRegisteredClientRepository(builder));
+		builder.authenticationProvider(postProcess(clientAuthenticationProvider));
+
+		OAuth2AuthorizationCodeAuthenticationProvider authorizationCodeAuthenticationProvider =
+				new OAuth2AuthorizationCodeAuthenticationProvider(
+						getRegisteredClientRepository(builder),
+						getAuthorizationService(builder));
+		builder.authenticationProvider(postProcess(authorizationCodeAuthenticationProvider));
+	}
+
+	@Override
+	public void configure(B builder) {
+		AuthenticationManager authenticationManager = builder.getSharedObject(AuthenticationManager.class);
+
+		OAuth2ClientAuthenticationFilter clientAuthenticationFilter =
+				new OAuth2ClientAuthenticationFilter(
+						authenticationManager,
+						new AntPathRequestMatcher(OAuth2TokenEndpointFilter.DEFAULT_TOKEN_ENDPOINT_URI, HttpMethod.POST.name()));
+		builder.addFilterAfter(postProcess(clientAuthenticationFilter), AbstractPreAuthenticatedProcessingFilter.class);
+
+		OAuth2AuthorizationEndpointFilter authorizationEndpointFilter =
+				new OAuth2AuthorizationEndpointFilter(
+						getRegisteredClientRepository(builder),
+						getAuthorizationService(builder));
+		builder.addFilterAfter(postProcess(authorizationEndpointFilter), FilterSecurityInterceptor.class);
+
+		OAuth2TokenEndpointFilter tokenEndpointFilter =
+				new OAuth2TokenEndpointFilter(
+						authenticationManager,
+						getAuthorizationService(builder));
+		builder.addFilterAfter(postProcess(tokenEndpointFilter), FilterSecurityInterceptor.class);
+	}
+
+	private static <B extends HttpSecurityBuilder<B>> RegisteredClientRepository getRegisteredClientRepository(B builder) {
+		RegisteredClientRepository registeredClientRepository = builder.getSharedObject(RegisteredClientRepository.class);
+		if (registeredClientRepository == null) {
+			registeredClientRepository = getRegisteredClientRepositoryBean(builder);
+			builder.setSharedObject(RegisteredClientRepository.class, registeredClientRepository);
+		}
+		return registeredClientRepository;
+	}
+
+	private static <B extends HttpSecurityBuilder<B>> RegisteredClientRepository getRegisteredClientRepositoryBean(B builder) {
+		return builder.getSharedObject(ApplicationContext.class).getBean(RegisteredClientRepository.class);
+	}
+
+	private static <B extends HttpSecurityBuilder<B>> OAuth2AuthorizationService getAuthorizationService(B builder) {
+		OAuth2AuthorizationService authorizationService = builder.getSharedObject(OAuth2AuthorizationService.class);
+		if (authorizationService == null) {
+			authorizationService = getAuthorizationServiceBean(builder);
+			if (authorizationService == null) {
+				authorizationService = new InMemoryOAuth2AuthorizationService();
+			}
+			builder.setSharedObject(OAuth2AuthorizationService.class, authorizationService);
+		}
+		return authorizationService;
+	}
+
+	private static <B extends HttpSecurityBuilder<B>> OAuth2AuthorizationService getAuthorizationServiceBean(B builder) {
+		Map<String, OAuth2AuthorizationService> authorizationServiceMap = BeanFactoryUtils.beansOfTypeIncludingAncestors(
+				builder.getSharedObject(ApplicationContext.class), OAuth2AuthorizationService.class);
+		if (authorizationServiceMap.size() > 1) {
+			throw new NoUniqueBeanDefinitionException(OAuth2AuthorizationService.class, authorizationServiceMap.size(),
+					"Expected single matching bean of type '" + OAuth2AuthorizationService.class.getName() + "' but found " +
+							authorizationServiceMap.size() + ": " + StringUtils.collectionToCommaDelimitedString(authorizationServiceMap.keySet()));
+		}
+		return (!authorizationServiceMap.isEmpty() ? authorizationServiceMap.values().iterator().next() : null);
+	}
+}