Use Schedulers.boundedElastic()

Fixes gh-7457

Author: rwinch

core/src/main/java/org/springframework/security/authentication/ReactiveAuthenticationManagerAdapter.java

@@ -34,7 +34,7 @@
 public class ReactiveAuthenticationManagerAdapter implements ReactiveAuthenticationManager {
 	private final AuthenticationManager authenticationManager;
 
-	private Scheduler scheduler = Schedulers.elastic();
+	private Scheduler scheduler = Schedulers.boundedElastic();
 
 	public ReactiveAuthenticationManagerAdapter(AuthenticationManager authenticationManager) {
 		Assert.notNull(authenticationManager, "authenticationManager cannot be null");

gradle/dependency-management.gradle

@@ -1,5 +1,5 @@
 if (!project.hasProperty('reactorVersion')) {
-	ext.reactorVersion = 'Dysprosium-RC1'
+	ext.reactorVersion = 'Dysprosium-BUILD-SNAPSHOT'
 }
 
 if (!project.hasProperty('springVersion')) {

oauth2/oauth2-client/src/main/java/org/springframework/security/oauth2/client/web/reactive/function/client/ServletOAuth2AuthorizedClientExchangeFilterFunction.java

@@ -463,9 +463,10 @@ private Mono<OAuth2AuthorizedClient> authorizeClient(String clientRegistrationId
 		});
 		OAuth2AuthorizeRequest authorizeRequest = builder.build();
 
-		// NOTE: 'authorizedClientManager.authorize()' needs to be executed on a dedicated thread via subscribeOn(Schedulers.elastic())
+		// NOTE: 'authorizedClientManager.authorize()' needs to be executed on a dedicated thread via subscribeOn(Schedulers.boundedElastic())
+		// NOTE: 'authorizedClientManager.authorize()' needs to be executed on a dedicated thread via subscribeOn(Schedulers.boundedElastic())
 		// since it performs a blocking I/O operation using RestTemplate internally
-		return Mono.fromSupplier(() -> this.authorizedClientManager.authorize(authorizeRequest)).subscribeOn(Schedulers.elastic());
+		return Mono.fromSupplier(() -> this.authorizedClientManager.authorize(authorizeRequest)).subscribeOn(Schedulers.boundedElastic());
 	}
 
 	private Mono<OAuth2AuthorizedClient> authorizedClient(OAuth2AuthorizedClient authorizedClient, ClientRequest request) {
@@ -491,9 +492,9 @@ private Mono<OAuth2AuthorizedClient> authorizedClient(OAuth2AuthorizedClient aut
 		});
 		OAuth2AuthorizeRequest reauthorizeRequest = builder.build();
 
-		// NOTE: 'authorizedClientManager.authorize()' needs to be executed on a dedicated thread via subscribeOn(Schedulers.elastic())
+		// NOTE: 'authorizedClientManager.authorize()' needs to be executed on a dedicated thread via subscribeOn(Schedulers.boundedElastic())
 		// since it performs a blocking I/O operation using RestTemplate internally
-		return Mono.fromSupplier(() -> this.authorizedClientManager.authorize(reauthorizeRequest)).subscribeOn(Schedulers.elastic());
+		return Mono.fromSupplier(() -> this.authorizedClientManager.authorize(reauthorizeRequest)).subscribeOn(Schedulers.boundedElastic());
 	}
 
 	private ClientRequest bearer(ClientRequest request, OAuth2AuthorizedClient authorizedClient) {