Add How-to: Authenticate using Social Login

Closes gh-538

samples/demo-authorizationserver/src/main/java/sample/federation/FederatedIdentityAuthenticationEntryPoint.java

@@ -15,6 +15,7 @@
  */
 package sample.federation;
 
+// tag::imports[]
 import java.io.IOException;
 
 import jakarta.servlet.ServletException;
@@ -31,6 +32,7 @@ import org.springframework.security.web.DefaultRedirectStrategy;
 import org.springframework.security.web.RedirectStrategy;
 import org.springframework.security.web.authentication.LoginUrlAuthenticationEntryPoint;
 import org.springframework.web.util.UriComponentsBuilder;
+// end::imports[]
 
 /**
  * An {@link AuthenticationEntryPoint} for initiating the login flow to an
@@ -40,6 +42,7 @@ import org.springframework.web.util.UriComponentsBuilder;
  * @author Steve Riesenberg
  * @since 1.1
  */
+// tag::class[]
 public final class FederatedIdentityAuthenticationEntryPoint implements AuthenticationEntryPoint {
 
 	private final RedirectStrategy redirectStrategy = new DefaultRedirectStrategy();
@@ -80,3 +83,4 @@ public final class FederatedIdentityAuthenticationEntryPoint implements Authenti
 	}
 
 }
+// end::class[]

samples/demo-authorizationserver/src/main/java/sample/federation/FederatedIdentityAuthenticationSuccessHandler.java

@@ -15,6 +15,7 @@
  */
 package sample.federation;
 
+// tag::imports[]
 import java.io.IOException;
 import java.util.function.Consumer;
 
@@ -28,6 +29,7 @@ import org.springframework.security.oauth2.core.oidc.user.OidcUser;
 import org.springframework.security.oauth2.core.user.OAuth2User;
 import org.springframework.security.web.authentication.AuthenticationSuccessHandler;
 import org.springframework.security.web.authentication.SavedRequestAwareAuthenticationSuccessHandler;
+// end::imports[]
 
 /**
  * An {@link AuthenticationSuccessHandler} for capturing the {@link OidcUser} or
@@ -36,6 +38,7 @@ import org.springframework.security.web.authentication.SavedRequestAwareAuthenti
  * @author Steve Riesenberg
  * @since 1.1
  */
+// tag::class[]
 public final class FederatedIdentityAuthenticationSuccessHandler implements AuthenticationSuccessHandler {
 
 	private final AuthenticationSuccessHandler delegate = new SavedRequestAwareAuthenticationSuccessHandler();
@@ -66,3 +69,4 @@ public final class FederatedIdentityAuthenticationSuccessHandler implements Auth
 	}
 
 }
+// end::class[]

samples/demo-authorizationserver/src/main/java/sample/federation/FederatedIdentityConfigurer.java

@@ -15,6 +15,7 @@
  */
 package sample.federation;
 
+// tag::imports[]
 import java.util.function.Consumer;
 
 import org.springframework.context.ApplicationContext;
@@ -24,6 +25,7 @@ import org.springframework.security.oauth2.client.registration.ClientRegistratio
 import org.springframework.security.oauth2.core.oidc.user.OidcUser;
 import org.springframework.security.oauth2.core.user.OAuth2User;
 import org.springframework.util.Assert;
+// end::imports[]
 
 /**
  * A configurer for setting up Federated Identity Management.
@@ -31,6 +33,7 @@ import org.springframework.util.Assert;
  * @author Steve Riesenberg
  * @since 1.1
  */
+// tag::class[]
 public final class FederatedIdentityConfigurer extends AbstractHttpConfigurer<FederatedIdentityConfigurer, HttpSecurity> {
 
 	private String loginPageUrl = "/login";
@@ -123,3 +126,4 @@ public final class FederatedIdentityConfigurer extends AbstractHttpConfigurer<Fe
 	// @formatter:on
 
 }
+// end::class[]

samples/demo-authorizationserver/src/main/java/sample/federation/FederatedIdentityIdTokenCustomizer.java

@@ -15,6 +15,7 @@
  */
 package sample.federation;
 
+// tag::imports[]
 import java.util.Arrays;
 import java.util.Collections;
 import java.util.HashMap;
@@ -30,6 +31,7 @@ import org.springframework.security.oauth2.core.oidc.user.OidcUser;
 import org.springframework.security.oauth2.core.user.OAuth2User;
 import org.springframework.security.oauth2.server.authorization.token.JwtEncodingContext;
 import org.springframework.security.oauth2.server.authorization.token.OAuth2TokenCustomizer;
+// end::imports[]
 
 /**
  * An {@link OAuth2TokenCustomizer} to map claims from a federated identity to
@@ -38,6 +40,7 @@ import org.springframework.security.oauth2.server.authorization.token.OAuth2Toke
  * @author Steve Riesenberg
  * @since 1.1
  */
+// tag::class[]
 public final class FederatedIdentityIdTokenCustomizer implements OAuth2TokenCustomizer<JwtEncodingContext> {
 
 	private static final Set<String> ID_TOKEN_CLAIMS = Collections.unmodifiableSet(new HashSet<>(Arrays.asList(
@@ -89,3 +92,4 @@ public final class FederatedIdentityIdTokenCustomizer implements OAuth2TokenCust
 	}
 
 }
+// end::class[]

samples/demo-authorizationserver/src/main/java/sample/federation/UserRepositoryOAuth2UserHandler.java

@@ -15,11 +15,13 @@
  */
 package sample.federation;
 
+// tag::imports[]
 import java.util.Map;
 import java.util.concurrent.ConcurrentHashMap;
 import java.util.function.Consumer;
 
 import org.springframework.security.oauth2.core.user.OAuth2User;
+// end::imports[]
 
 /**
  * Example {@link Consumer} to perform JIT provisioning of an {@link OAuth2User}.
@@ -27,6 +29,7 @@ import org.springframework.security.oauth2.core.user.OAuth2User;
  * @author Steve Riesenberg
  * @since 1.1
  */
+// tag::class[]
 public final class UserRepositoryOAuth2UserHandler implements Consumer<OAuth2User> {
 
 	private final UserRepository userRepository = new UserRepository();
@@ -55,3 +58,4 @@ public final class UserRepositoryOAuth2UserHandler implements Consumer<OAuth2Use
 	}
 
 }
+// end::class[]