[[servlet-authorization-authorizationfilter]]
= Authorize HttpServletRequests with AuthorizationFilter
:figures: servlet/authorization

This section builds on xref:servlet/architecture.adoc#servlet-architecture[Servlet Architecture and Implementation] by digging deeper into how xref:servlet/authorization/index.adoc#servlet-authorization[authorization] works within Servlet-based applications.

[NOTE]
`AuthorizationFilter` supersedes xref:servlet/authorization/authorize-requests.adoc#servlet-authorization-filtersecurityinterceptor[`FilterSecurityInterceptor`].
To remain backward compatible, `FilterSecurityInterceptor` remains the default.
This section discusses how `AuthorizationFilter` works and how to override the default configuration.

The {security-api-url}org/springframework/security/web/access/intercept/AuthorizationFilter.html[`AuthorizationFilter`] provides xref:servlet/authorization/index.adoc#servlet-authorization[authorization] for ``HttpServletRequest``s.
It is inserted into the xref:servlet/architecture.adoc#servlet-filterchainproxy[FilterChainProxy] as one of the xref:servlet/architecture.adoc#servlet-security-filters[Security Filters].

You can override the default when you declare a `SecurityFilterChain`.
Instead of using xref:servlet/authorization/authorize-http-requests.adoc#servlet-authorize-requests-defaults[`authorizeRequests`], use `authorizeHttpRequests`, like so:

.Use authorizeHttpRequests
====
.Java
[source,java,role="primary"]
----
@Bean
SecurityFilterChain web(HttpSecurity http) throws AuthenticationException {
    http
        .authorizeHttpRequests((authorize) -> authorize
            .anyRequest().authenticated();
        )
        // ...

    return http.build();
}
----
====

This improves on `authorizeRequests` in a number of ways:

1. Uses the simplified `AuthorizationManager` API instead of metadata sources, config attributes, decision managers, and voters.
This simplifies reuse and customization.
2. Delays `Authentication` lookup.
Instead of the authentication needing to be looked up for every request, it will only look it up in requests where an authorization decision requires authentication.
3. Bean-based configuration support.

When `authorizeHttpRequests` is used instead of `authorizeRequests`, then {security-api-url}org/springframework/security/web/access/intercept/AuthorizationFilter.html[`AuthorizationFilter`] is used instead of xref:servlet/authorization/authorize-requests.adoc#servlet-authorization-filtersecurityinterceptor[`FilterSecurityInterceptor`].

.Authorize HttpServletRequest
image::{figures}/authorizationfilter.png[]

* image:{icondir}/number_1.png[] First, the `AuthorizationFilter` obtains an  xref:servlet/authentication/architecture.adoc#servlet-authentication-authentication[Authentication] from the xref:servlet/authentication/architecture.adoc#servlet-authentication-securitycontextholder[SecurityContextHolder].
It wraps this in an `Supplier` in order to delay lookup.
* image:{icondir}/number_2.png[] Second, it passes the `Supplier<Authentication>` and the `HttpServletRequest` to the xref:servlet/architecture.adoc#authz-authorization-manager[`AuthorizationManager`].
** image:{icondir}/number_3.png[] If authorization is denied, an `AccessDeniedException` is thrown.
In this case the xref:servlet/architecture.adoc#servlet-exceptiontranslationfilter[`ExceptionTranslationFilter`] handles the `AccessDeniedException`.
** image:{icondir}/number_4.png[] If access is granted, `AuthorizationFilter` continues with the xref:servlet/architecture.adoc#servlet-filters-review[FilterChain] which allows the application to process normally.

We can configure Spring Security to have different rules by adding more rules in order of precedence.

.Authorize Requests
====
.Java
[source,java,role="primary"]
----
@Bean
SecurityFilterChain web(HttpSecurity http) throws Exception {
	http
		// ...
		.authorizeHttpRequests(authorize -> authorize                                  // <1>
			.requestMatchers("/resources/**", "/signup", "/about").permitAll()         // <2>
			.requestMatchers("/admin/**").hasRole("ADMIN")                             // <3>
			.requestMatchers("/db/**").access(new WebExpressionAuthorizationManager("hasRole('ADMIN') and hasRole('DBA')"))   // <4>
			// .requestMatchers("/db/**").access(AuthorizationManagers.allOf(AuthorityAuthorizationManager.hasRole("ADMIN"), AuthorityAuthorizationManager.hasRole("DBA")))   // <5>
			.anyRequest().denyAll()                                                // <6>
		);

	return http.build();
}
----
====
<1> There are multiple authorization rules specified.
Each rule is considered in the order they were declared.
<2> We specified multiple URL patterns that any user can access.
Specifically, any user can access a request if the URL starts with "/resources/", equals "/signup", or equals "/about".
<3> Any URL that starts with "/admin/" will be restricted to users who have the role "ROLE_ADMIN".
You will notice that since we are invoking the `hasRole` method we do not need to specify the "ROLE_" prefix.
<4> Any URL that starts with "/db/" requires the user to have both "ROLE_ADMIN" and "ROLE_DBA".
You will notice that since we are using the `hasRole` expression we do not need to specify the "ROLE_" prefix.
<5> The same rule from 4, could be written by combining multiple `AuthorizationManager`.
<6> Any URL that has not already been matched on is denied access.
This is a good strategy if you do not want to accidentally forget to update your authorization rules.

You can take a bean-based approach by constructing your own xref:servlet/authorization/architecture.adoc#authz-delegate-authorization-manager[`RequestMatcherDelegatingAuthorizationManager`] like so:

.Configure RequestMatcherDelegatingAuthorizationManager
====
.Java
[source,java,role="primary"]
----
@Bean
SecurityFilterChain web(HttpSecurity http, AuthorizationManager<RequestAuthorizationContext> access)
        throws AuthenticationException {
    http
        .authorizeHttpRequests((authorize) -> authorize
            .anyRequest().access(access)
        )
        // ...

    return http.build();
}

@Bean
AuthorizationManager<RequestAuthorizationContext> requestMatcherAuthorizationManager(HandlerMappingIntrospector introspector) {
    MvcRequestMatcher.Builder mvcMatcherBuilder = new MvcRequestMatcher.Builder(introspector);
    RequestMatcher permitAll =
            new AndRequestMatcher(
                    mvcMatcherBuilder.pattern("/resources/**"),
                    mvcMatcherBuilder.pattern("/signup"),
                    mvcMatcherBuilder.pattern("/about"));
    RequestMatcher admin = mvcMatcherBuilder.pattern("/admin/**");
    RequestMatcher db = mvcMatcherBuilder.pattern("/db/**");
    RequestMatcher any = AnyRequestMatcher.INSTANCE;
    AuthorizationManager<HttpServletRequest> manager = RequestMatcherDelegatingAuthorizationManager.builder()
            .add(permitAll, (context) -> new AuthorizationDecision(true))
            .add(admin, AuthorityAuthorizationManager.hasRole("ADMIN"))
            .add(db, AuthorityAuthorizationManager.hasRole("DBA"))
            .add(any, new AuthenticatedAuthorizationManager())
            .build();
    return (context) -> manager.check(context.getRequest());
}
----
====

You can also wire xref:servlet/authorization/architecture.adoc#authz-custom-authorization-manager[your own custom authorization managers] for any request matcher.

Here is an example of mapping a custom authorization manager to the `my/authorized/endpoint`:

.Custom Authorization Manager
====
.Java
[source,java,role="primary"]
----
@Bean
SecurityFilterChain web(HttpSecurity http) throws Exception {
    http
        .authorizeHttpRequests((authorize) -> authorize
            .requestMatchers("/my/authorized/endpoint").access(new CustomAuthorizationManager());
        )
        // ...

    return http.build();
}
----
====

Or you can provide it for all requests as seen below:

.Custom Authorization Manager for All Requests
====
.Java
[source,java,role="primary"]
----
@Bean
SecurityFilterChain web(HttpSecurity http) throws Exception {
    http
        .authorizeHttpRequests((authorize) -> authorize
            .anyRequest().access(new CustomAuthorizationManager());
        )
        // ...

    return http.build();
}
----
====

By default, the `AuthorizationFilter` applies to all dispatcher types.
We can configure Spring Security to not apply the authorization rules to all dispatcher types by using the `shouldFilterAllDispatcherTypes` method:

.Set shouldFilterAllDispatcherTypes to false
====
.Java
[source,java,role="primary"]
----
@Bean
SecurityFilterChain web(HttpSecurity http) throws Exception {
    http
        .authorizeHttpRequests((authorize) -> authorize
            .shouldFilterAllDispatcherTypes(false)
            .anyRequest().authenticated()
        )
        // ...

    return http.build();
}
----
.Kotlin
[source,kotlin,role="secondary"]
----
@Bean
open fun web(http: HttpSecurity): SecurityFilterChain {
    http {
        authorizeHttpRequests {
            shouldFilterAllDispatcherTypes = false
            authorize(anyRequest, authenticated)
        }
    }
    return http.build()
}
----
====

Instead of setting `shouldFilterAllDispatcherTypes` to `false`, the recommended approach is to customize authorization on the dispatcher types.
For example, you may want to grant all access on requests with dispatcher type `ASYNC` or `FORWARD`.

.Permit ASYNC and FORWARD dispatcher type
====
.Java
[source,java,role="primary"]
----
@Bean
SecurityFilterChain web(HttpSecurity http) throws Exception {
    http
        .authorizeHttpRequests((authorize) -> authorize
            .dispatcherTypeMatchers(DispatcherType.ASYNC, DispatcherType.FORWARD).permitAll()
            .anyRequest().authenticated()
        )
        // ...

    return http.build();
}
----
.Kotlin
[source,kotlin,role="secondary"]
----
@Bean
open fun web(http: HttpSecurity): SecurityFilterChain {
    http {
        authorizeHttpRequests {
            authorize(DispatcherTypeRequestMatcher(DispatcherType.ASYNC, DispatcherType.FORWARD), permitAll)
            authorize(anyRequest, authenticated)
        }
    }
    return http.build()
}
----
====

You can also customize it to require a specific role for a dispatcher type:

.Require ADMIN for Dispatcher Type ERROR
====
.Java
[source,java,role="primary"]
----
@Bean
SecurityFilterChain web(HttpSecurity http) throws Exception {
    http
        .authorizeHttpRequests((authorize) -> authorize
            .dispatcherTypeMatchers(DispatcherType.ERROR).hasRole("ADMIN")
            .anyRequest().authenticated()
        )
        // ...

    return http.build();
}
----
.Kotlin
[source,kotlin,role="secondary"]
----
@Bean
open fun web(http: HttpSecurity): SecurityFilterChain {
    http {
        authorizeHttpRequests {
            authorize(DispatcherTypeRequestMatcher(DispatcherType.ERROR), hasRole("ADMIN"))
            authorize(anyRequest, authenticated)
        }
    }
    return http.build()
}
----
====

== Request Matchers

The `RequestMatcher` interface is used to determine if a request matches a given rule.
We use `securityMatchers` to determine if a given `HttpSecurity` should be applied to a given request.
The same way, we can use `requestMatchers` to determine the authorization rules that we should apply to a given request.
Look at the following example:

====
.Java
[source,java,role="primary"]
----
@Configuration
@EnableWebSecurity
public class SecurityConfig {

	@Bean
	public SecurityFilterChain securityFilterChain(HttpSecurity http) throws Exception {
		http
			.securityMatcher("/api/**")                            <1>
			.authorizeHttpRequests(authorize -> authorize
				.requestMatchers("/user/**").hasRole("USER")       <2>
				.requestMatchers("/admin/**").hasRole("ADMIN")     <3>
				.anyRequest().authenticated()                      <4>
			)
			.formLogin(withDefaults());
		return http.build();
	}
}
----
.Kotlin
[source,kotlin,role="secondary"]
----
@Configuration
@EnableWebSecurity
open class SecurityConfig {

    @Bean
    open fun web(http: HttpSecurity): SecurityFilterChain {
        http {
            securityMatcher("/api/**")                                           <1>
            authorizeHttpRequests {
                authorize("/user/**", hasRole("USER"))                           <2>
                authorize("/admin/**", hasRole("ADMIN"))                         <3>
                authorize(anyRequest, authenticated)                             <4>
            }
        }
        return http.build()
    }

}
----
====

<1> Configure `HttpSecurity` to only be applied to URLs that start with `/api/`
<2> Allow access to URLs that start with `/user/` to users with the `USER` role
<3> Allow access to URLs that start with `/admin/` to users with the `ADMIN` role
<4> Any other request that doesn't match the rules above, will require authentication

The `securityMatcher(s)` and `requestMatcher(s)` methods will decide which `RequestMatcher` implementation fits best for your application: If Spring MVC is in the classpath, then `MvcRequestMatcher` will be used, otherwise, `AntPathRequestMatcher` will be used.
You can read more about the Spring MVC integration xref:servlet/integrations/mvc.adoc[here].

If you want to use a specific `RequestMatcher`, just pass an implementation to the `securityMatcher` and/or `requestMatcher` methods:

====
.Java
[source,java,role="primary"]
----
import static org.springframework.security.web.util.matcher.AntPathRequestMatcher.antMatcher; <1>
import static org.springframework.security.web.util.matcher.RegexRequestMatcher.regexMatcher;

@Configuration
@EnableWebSecurity
public class SecurityConfig {

	@Bean
	public SecurityFilterChain securityFilterChain(HttpSecurity http) throws Exception {
		http
			.securityMatcher(antMatcher("/api/**"))                              <2>
			.authorizeHttpRequests(authorize -> authorize
				.requestMatchers(antMatcher("/user/**")).hasRole("USER")         <3>
				.requestMatchers(regexMatcher("/admin/.*")).hasRole("ADMIN")     <4>
				.requestMatchers(new MyCustomRequestMatcher()).hasRole("SUPERVISOR")     <5>
				.anyRequest().authenticated()
			)
			.formLogin(withDefaults());
		return http.build();
	}
}

public class MyCustomRequestMatcher implements RequestMatcher {

    @Override
    public boolean matches(HttpServletRequest request) {
        // ...
    }
}
----
.Kotlin
[source,kotlin,role="secondary"]
----
import org.springframework.security.web.util.matcher.AntPathRequestMatcher.antMatcher <1>
import org.springframework.security.web.util.matcher.RegexRequestMatcher.regexMatcher

@Configuration
@EnableWebSecurity
open class SecurityConfig {

    @Bean
    open fun web(http: HttpSecurity): SecurityFilterChain {
        http {
            securityMatcher(antMatcher("/api/**"))                               <2>
            authorizeHttpRequests {
                authorize(antMatcher("/user/**"), hasRole("USER"))               <3>
                authorize(regexMatcher("/admin/**"), hasRole("ADMIN"))           <4>
                authorize(MyCustomRequestMatcher(), hasRole("SUPERVISOR"))       <5>
                authorize(anyRequest, authenticated)
            }
        }
        return http.build()
    }

}
----
====

<1> Import the static factory methods from `AntPathRequestMatcher` and `RegexRequestMatcher` to create `RequestMatcher` instances.
<2> Configure `HttpSecurity` to only be applied to URLs that start with `/api/`, using `AntPathRequestMatcher`
<3> Allow access to URLs that start with `/user/` to users with the `USER` role, using `AntPathRequestMatcher`
<4> Allow access to URLs that start with `/admin/` to users with the `ADMIN` role, using `RegexRequestMatcher`
<5> Allow access to URLs that match the `MyCustomRequestMatcher` to users with the `SUPERVISOR` role, using a custom `RequestMatcher`
