Simple AuthN & AuthZ example with Spring Boot / Security / Session

App.java

package demo;

import java.io.Serializable;
import java.security.Principal;
import java.util.Collection;
import java.util.Collections;
import java.util.HashMap;
import java.util.Map;
import java.util.UUID;

import javax.servlet.http.HttpSession;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.ApplicationContext;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.security.access.PermissionEvaluator;
import org.springframework.security.access.annotation.Secured;
import org.springframework.security.access.expression.method.DefaultMethodSecurityExpressionHandler;
import org.springframework.security.access.expression.method.MethodSecurityExpressionHandler;
import org.springframework.security.access.prepost.PreAuthorize;
import org.springframework.security.config.annotation.authentication.builders.AuthenticationManagerBuilder;
import org.springframework.security.config.annotation.method.configuration.EnableGlobalMethodSecurity;
import org.springframework.security.config.annotation.method.configuration.GlobalMethodSecurityConfiguration;
import org.springframework.security.config.annotation.web.builders.HttpSecurity;
import org.springframework.security.config.annotation.web.configuration.EnableWebSecurity;
import org.springframework.security.config.annotation.web.configuration.WebSecurityConfigurerAdapter;
import org.springframework.security.core.Authentication;
import org.springframework.security.core.GrantedAuthority;
import org.springframework.security.core.annotation.AuthenticationPrincipal;
import org.springframework.security.web.savedrequest.NullRequestCache;
import org.springframework.session.ExpiringSession;
import org.springframework.session.MapSessionRepository;
import org.springframework.session.SessionRepository;
import org.springframework.session.config.annotation.web.http.EnableSpringHttpSession;
import org.springframework.session.web.http.HeaderHttpSessionStrategy;
import org.springframework.session.web.http.HttpSessionStrategy;
import org.springframework.stereotype.Component;
import org.springframework.util.CollectionUtils;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

import lombok.Data;
import lombok.Value;
import lombok.extern.slf4j.Slf4j;

/**
 * <pre>
 * {@code
 *  export BASE_URL=http://localhost:17777
 * 
 *  curl --noproxy localhost -u user:password -v $BASE_URL/api/auth
 *  export AUTH_TOKEN=...
 *  curl --noproxy localhost -H "x-auth-token: $AUTH_TOKEN" -v $BASE_URL/api/greet
 *  curl --noproxy localhost -H "x-auth-token: $AUTH_TOKEN" -v -d "amount=42.0"  $BASE_URL/api/order
 *  curl --noproxy localhost -H "x-auth-token: $AUTH_TOKEN" -v -d "amount=1000.0"  $BASE_URL/api/order
 *  
 *  curl --noproxy localhost -u admin:password -v $BASE_URL/api/auth
 *  export AUTH_TOKEN=...
 *  curl --noproxy localhost -H "x-auth-token: $AUTH_TOKEN" -v -d "amount=1000.0"  $BASE_URL/api/order
 *  }
 * </pre>
 *
 */
@SpringBootApplication
public class App {

	public static void main(String[] args) {
		SpringApplication.run(App.class, args);
	}
}

@Configuration
@EnableSpringHttpSession
class HttpSessionConfig {

	@Bean
	SessionRepository<ExpiringSession> inmemorySessionRepository() {
		return new MapSessionRepository();
	}

	@Bean
	HttpSessionStrategy httpSessionStrategy() {
		return new HeaderHttpSessionStrategy();
	}
}

@Configuration
@EnableGlobalMethodSecurity(prePostEnabled = true, securedEnabled = true)
class SecurityConfig extends GlobalMethodSecurityConfiguration {

	@Autowired
	private DomainAwarePermissionEvaluator permissionEvaluator;

	@Autowired
	private ApplicationContext applicationContext;

	@Override
	protected MethodSecurityExpressionHandler createExpressionHandler() {

		DefaultMethodSecurityExpressionHandler expressionHandler = new DefaultMethodSecurityExpressionHandler();
		expressionHandler.setPermissionEvaluator(permissionEvaluator);
		expressionHandler.setApplicationContext(applicationContext);

		return expressionHandler;
	}
}

@EnableWebSecurity
@EnableGlobalMethodSecurity(prePostEnabled = true, securedEnabled = true)
class WebSecurityConfig extends WebSecurityConfigurerAdapter {

	@Override
	protected void configure(HttpSecurity http) throws Exception {
		http.authorizeRequests() //
				.anyRequest().authenticated() //
				.and().requestCache().requestCache(new NullRequestCache()) //
				.and().httpBasic() //
				.and().csrf().disable();
	}

	@Autowired
	void configureGlobal(AuthenticationManagerBuilder auth) throws Exception {
		auth.inMemoryAuthentication() //
				.withUser("user").password("password").authorities("ROLE_USER") //
				.and() //
				.withUser("admin").password("password").authorities("ROLE_USER", "ROLE_ADMIN");
	}
}

@Slf4j
@Component
class DomainAwarePermissionEvaluator implements PermissionEvaluator {

	@Override
	public boolean hasPermission(Authentication authentication, Object targetDomainObject, Object permission) {

		log.info("check permission '{}' for user '{}' for target '{}'", permission, authentication.getName(),
				targetDomainObject);

		if ("place-order".equals(permission)) {
			Order order = (Order) targetDomainObject;
			if (order.getAmount() > 500) {
				return hasRole("ROLE_ADMIN", authentication);
			}
		}

		return true;
	}

	@Override
	public boolean hasPermission(Authentication authentication, Serializable targetId, String targetType,
			Object permission) {
		return hasPermission(authentication, new DomainObjectReference(targetId, targetType), permission);
	}

	private boolean hasRole(String role, Authentication auth) {

		if (auth == null || auth.getPrincipal() == null) {
			return false;
		}

		Collection<? extends GrantedAuthority> authorities = auth.getAuthorities();

		if (CollectionUtils.isEmpty(authorities)) {
			return false;
		}

		return authorities.stream().filter(ga -> role.equals(ga.getAuthority())).findAny().isPresent();
	}

	@Value
	static class DomainObjectReference {
		private final Serializable targetId;
		private final String targetType;
	}
}

@RequestMapping("/api/auth")
@RestController
class AuthEndpoint {

	@GetMapping
	Map<String, Object> getToken(HttpSession session) {
		return Collections.singletonMap("session", session.getId());
	}
}

@Secured("ROLE_USER")
@RequestMapping("/api/greet")
@RestController
class GreetingEndpoint {

	@GetMapping
	Map<String, Object> greet(@AuthenticationPrincipal Principal user) {

		Map<String, Object> map = new HashMap<>();
		map.put("user", user.getName());
		return map;
	}
}

@Secured("ROLE_USER")
@RequestMapping("/api/order")
@RestController
class OrderEndpoint {

	@PostMapping
	@PreAuthorize("hasPermission(#order, 'place-order')")
	Map<String, Object> newOrder(Order order) {

		Map<String, Object> map = new HashMap<>();
		map.put("orderId", UUID.randomUUID());
		return map;
	}
}

@Data
class Order {
	double amount;
}

@RequestMapping("/api/admin")
@RestController
class AdminEndpoint {

	@GetMapping
	@Secured("ROLE_ADMIN")
	Map<String, Object> manage(@AuthenticationPrincipal Principal user) {
		return Collections.singletonMap("user", user.getName());
	}
}

application.properties

server.port=17777

pom.xml

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
	xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
	<modelVersion>4.0.0</modelVersion>

	<groupId>de.tdlabs</groupId>
	<artifactId>spring-boot-secure-rest-api-example</artifactId>
	<version>0.0.1.BUILD-SNAPSHOT</version>
	<packaging>jar</packaging>

	<name>spring-boot-secure-rest-api-example</name>
	<description>Demo project for Spring Boot</description>

	<parent>
		<groupId>org.springframework.boot</groupId>
		<artifactId>spring-boot-starter-parent</artifactId>
		<version>1.4.3.RELEASE</version>
		<relativePath /> <!-- lookup parent from repository -->
	</parent>

	<properties>
		<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
		<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
		<java.version>1.8</java.version>
	</properties>

	<dependencies>
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-security</artifactId>
		</dependency>

		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-web</artifactId>
		</dependency>

		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-devtools</artifactId>
		</dependency>

		<dependency>
			<groupId>org.springframework.session</groupId>
			<artifactId>spring-session</artifactId>
		</dependency>

		<dependency>
			<groupId>org.projectlombok</groupId>
			<artifactId>lombok</artifactId>
		</dependency>

		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-test</artifactId>
			<scope>test</scope>
		</dependency>
	</dependencies>

	<build>
		<plugins>
			<plugin>
				<groupId>org.springframework.boot</groupId>
				<artifactId>spring-boot-maven-plugin</artifactId>
			</plugin>
		</plugins>
	</build>
</project>