Add Default RSocketSecurity

Fixes gh-7361

rsocket/src/main/java/org/springframework/security/rsocket/core/SecuritySocketAcceptorInterceptor.java

@@ -0,0 +1,42 @@
+/*
+ * Copyright 2019 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.rsocket.core;
+
+import io.rsocket.SocketAcceptor;
+import io.rsocket.plugins.SocketAcceptorInterceptor;
+import org.springframework.util.Assert;
+
+/**
+ * A SocketAcceptorInterceptor that applies Security through a delegate {@link SocketAcceptorInterceptor}. This allows
+ * security to be applied lazily to an application.
+ *
+ * @author Rob Winch
+ * @since 5.2
+ */
+public class SecuritySocketAcceptorInterceptor implements SocketAcceptorInterceptor {
+	private final SocketAcceptorInterceptor acceptorInterceptor;
+
+	public SecuritySocketAcceptorInterceptor(SocketAcceptorInterceptor acceptorInterceptor) {
+		Assert.notNull(acceptorInterceptor, "acceptorInterceptor cannot be null");
+		this.acceptorInterceptor = acceptorInterceptor;
+	}
+
+	@Override
+	public SocketAcceptor apply(SocketAcceptor socketAcceptor) {
+		return this.acceptorInterceptor.apply(socketAcceptor);
+	}
+}