Update WebFlux samples to use Spring Boot

Fixes: gh-5411

samples/boot/hellowebflux/src/main/java/sample/HelloUserController.java

@@ -0,0 +1,44 @@
+/*
+ * Copyright 2002-2017 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
+ *
+ *      http://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 sample;
+
+import java.security.Principal;
+import java.util.Collections;
+import java.util.Map;
+
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.RestController;
+import reactor.core.publisher.Mono;
+
+/**
+ * @author Rob Winch
+ * @since 5.0
+ */
+@RestController
+public class HelloUserController {
+
+	@GetMapping("/")
+	public Mono<Map<String, String>> hello(Mono<Principal> principal) {
+		return principal
+			.map(Principal::getName)
+			.map(this::helloMessage);
+	}
+
+	private Map<String, String> helloMessage(String username) {
+		return Collections.singletonMap("message", "Hello " + username + "!");
+	}
+}

samples/boot/hellowebflux/src/main/java/sample/HelloWebfluxApplication.java

@@ -0,0 +1,33 @@
+/*
+ * Copyright 2002-2017 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
+ *
+ *      http://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 sample;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+
+/**
+ * @author Rob Winch
+ * @since 5.0
+ */
+@SpringBootApplication
+public class HelloWebfluxApplication {
+
+	public static void main(String[] args) {
+		SpringApplication.run(HelloWebfluxApplication.class, args);
+	}
+
+}

samples/boot/hellowebflux/src/main/java/sample/HelloWebfluxSecurityConfig.java

@@ -0,0 +1,41 @@
+/*
+ * Copyright 2002-2017 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
+ *
+ *      http://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 sample;
+
+import org.springframework.context.annotation.Bean;
+import org.springframework.security.config.annotation.web.reactive.EnableWebFluxSecurity;
+import org.springframework.security.core.userdetails.MapReactiveUserDetailsService;
+import org.springframework.security.core.userdetails.User;
+import org.springframework.security.core.userdetails.UserDetails;
+
+/**
+ * @author Rob Winch
+ * @since 5.0
+ */
+@EnableWebFluxSecurity
+public class HelloWebfluxSecurityConfig {
+
+	@Bean
+	public MapReactiveUserDetailsService userDetailsService() {
+		UserDetails user = User.withDefaultPasswordEncoder()
+			.username("user")
+			.password("user")
+			.roles("USER")
+			.build();
+		return new MapReactiveUserDetailsService(user);
+	}
+}