Merge pull request #4670 from Tonnix/master

Added BAEL-1867 project files under the Spring-5-Reactive Project

spring-5-reactive/src/main/java/com/baeldung/reactive/errorhandling/GlobalErrorAttributes.java

@@ -0,0 +1,55 @@
+
+package com.baeldung.reactive.errorhandling;
+
+import java.util.Map;
+import org.springframework.boot.web.reactive.error.DefaultErrorAttributes;
+import org.springframework.http.HttpStatus;
+import org.springframework.stereotype.Component;
+import org.springframework.web.reactive.function.server.ServerRequest;
+
+@Component
+public class GlobalErrorAttributes extends DefaultErrorAttributes{
+    
+    private HttpStatus status = HttpStatus.BAD_REQUEST;
+    private String message = "please provide a name";
+
+    public GlobalErrorAttributes() {
+        super(false); 
+    }
+
+    @Override
+    public Map<String, Object> getErrorAttributes(ServerRequest request, boolean includeStackTrace) {
+        Map<String, Object> map = super.getErrorAttributes(request, includeStackTrace);
+        map.put("status", getStatus());
+        map.put("message", getMessage());
+        return map;
+    }
+
+    /**
+     * @return the status
+     */
+    public HttpStatus getStatus() {
+        return status;
+    }
+
+    /**
+     * @param status the status to set
+     */
+    public void setStatus(HttpStatus status) {
+        this.status = status;
+    }
+
+    /**
+     * @return the message
+     */
+    public String getMessage() {
+        return message;
+    }
+
+    /**
+     * @param message the message to set
+     */
+    public void setMessage(String message) {
+        this.message = message;
+    }
+}

spring-5-reactive/src/main/java/com/baeldung/reactive/errorhandling/GlobalErrorWebExceptionHandler.java

@@ -0,0 +1,47 @@
+
+package com.baeldung.reactive.errorhandling;
+
+import java.util.Map;
+import org.springframework.boot.autoconfigure.web.ResourceProperties;
+import org.springframework.boot.autoconfigure.web.reactive.error.AbstractErrorWebExceptionHandler;
+import org.springframework.boot.web.reactive.error.ErrorAttributes;
+import org.springframework.context.ApplicationContext;
+import org.springframework.core.annotation.Order;
+import org.springframework.http.HttpStatus;
+import org.springframework.http.MediaType;
+import org.springframework.http.codec.ServerCodecConfigurer;
+import org.springframework.stereotype.Component;
+import org.springframework.web.reactive.function.BodyInserters;
+import org.springframework.web.reactive.function.server.RequestPredicates;
+import org.springframework.web.reactive.function.server.RouterFunction;
+import org.springframework.web.reactive.function.server.RouterFunctions;
+import org.springframework.web.reactive.function.server.ServerRequest;
+import org.springframework.web.reactive.function.server.ServerResponse;
+import reactor.core.publisher.Mono;
+
+@Component
+@Order(-2)
+public class GlobalErrorWebExceptionHandler extends AbstractErrorWebExceptionHandler {
+
+    public GlobalErrorWebExceptionHandler(GlobalErrorAttributes g, ApplicationContext applicationContext, 
+            ServerCodecConfigurer serverCodecConfigurer) {
+        super(g, new ResourceProperties(), applicationContext);
+        super.setMessageWriters(serverCodecConfigurer.getWriters());
+        super.setMessageReaders(serverCodecConfigurer.getReaders());
+    }
+
+    @Override
+    protected RouterFunction<ServerResponse> getRoutingFunction(final ErrorAttributes errorAttributes) {
+        return RouterFunctions.route(RequestPredicates.all(), this::renderErrorResponse);
+    }
+
+    private Mono<ServerResponse> renderErrorResponse(final ServerRequest request) {
+
+        final Map<String, Object> errorPropertiesMap = getErrorAttributes(request, false);
+
+        return ServerResponse.status(HttpStatus.BAD_REQUEST)
+            .contentType(MediaType.APPLICATION_JSON_UTF8)
+            .body(BodyInserters.fromObject(errorPropertiesMap));
+    }
+
+}

spring-5-reactive/src/main/java/com/baeldung/reactive/errorhandling/NameRequiredException.java

@@ -0,0 +1,12 @@
+
+package com.baeldung.reactive.errorhandling;
+
+import org.springframework.http.HttpStatus;
+import org.springframework.web.server.ResponseStatusException;
+
+public class NameRequiredException extends ResponseStatusException {
+    
+    public NameRequiredException(HttpStatus status, String message, Throwable e) {
+        super(status, message, e);
+    }
+}

spring-5-reactive/src/main/java/com/baeldung/reactive/errorhandling/handlers/Handler1.java

@@ -0,0 +1,29 @@
+
+package com.baeldung.reactive.errorhandling.handlers;
+
+import org.springframework.http.MediaType;
+import org.springframework.stereotype.Component;
+import org.springframework.web.reactive.function.server.ServerRequest;
+import org.springframework.web.reactive.function.server.ServerResponse;
+import reactor.core.publisher.Mono;
+
+@Component
+public class Handler1 {
+
+    public Mono<ServerResponse> handleRequest1(ServerRequest request) {
+        return sayHello(request).onErrorReturn("Hello, Stranger")
+            .flatMap(s -> ServerResponse.ok()
+                .contentType(MediaType.TEXT_PLAIN)
+                .syncBody(s));
+    }
+
+    private Mono<String> sayHello(ServerRequest request) {
+        try {
+            return Mono.just("Hello, " + request.queryParam("name")
+                .get());
+        } catch (Exception e) {
+            return Mono.error(e);
+        }
+    }
+
+}

spring-5-reactive/src/main/java/com/baeldung/reactive/errorhandling/handlers/Handler2.java

@@ -0,0 +1,38 @@
+
+package com.baeldung.reactive.errorhandling.handlers;
+
+import org.springframework.http.MediaType;
+import org.springframework.stereotype.Component;
+import org.springframework.web.reactive.function.server.ServerRequest;
+import org.springframework.web.reactive.function.server.ServerResponse;
+import reactor.core.publisher.Mono;
+
+@Component
+public class Handler2 {
+
+public Mono<ServerResponse> handleRequest2(ServerRequest request) {
+    return 
+        sayHello(request)
+            .flatMap(s -> ServerResponse.ok()
+                .contentType(MediaType.TEXT_PLAIN)
+                .syncBody(s))
+            .onErrorResume(e -> sayHelloFallback()
+                .flatMap(s -> ServerResponse.ok()
+                    .contentType(MediaType.TEXT_PLAIN)
+                    .syncBody(s)));
+}
+
+    private Mono<String> sayHello(ServerRequest request) {
+        try {
+            return Mono.just("Hello, " + request.queryParam("name")
+                .get());
+        } catch (Exception e) {
+            return Mono.error(e);
+        }
+    }
+
+    private Mono<String> sayHelloFallback() {
+        return Mono.just("Hello, Stranger");
+    }
+
+}

spring-5-reactive/src/main/java/com/baeldung/reactive/errorhandling/handlers/Handler3.java

@@ -0,0 +1,34 @@
+
+package com.baeldung.reactive.errorhandling.handlers;
+
+import org.springframework.http.MediaType;
+import org.springframework.stereotype.Component;
+import org.springframework.web.reactive.function.server.ServerRequest;
+import org.springframework.web.reactive.function.server.ServerResponse;
+import reactor.core.publisher.Mono;
+
+@Component
+public class Handler3 {
+
+    public Mono<ServerResponse> handleRequest3(ServerRequest request) {
+        return 
+            sayHello(request)
+              .flatMap(s -> ServerResponse.ok()
+                        .contentType(MediaType.TEXT_PLAIN)
+                        .syncBody(s))
+              .onErrorResume(e -> (Mono.just("Hi, I looked around for your name but found: " + 
+                    e.getMessage())).flatMap(s -> ServerResponse.ok()
+                .contentType(MediaType.TEXT_PLAIN)
+                .syncBody(s)));
+    }
+
+    private Mono<String> sayHello(ServerRequest request) {
+        try {
+            return Mono.just("Hello, " + request.queryParam("name")
+                .get());
+        } catch (Exception e) {
+            return Mono.error(e);
+        }
+    }
+
+}

spring-5-reactive/src/main/java/com/baeldung/reactive/errorhandling/handlers/Handler4.java

@@ -0,0 +1,30 @@
+
+package com.baeldung.reactive.errorhandling.handlers;
+
+import com.baeldung.reactive.errorhandling.NameRequiredException;
+import org.springframework.http.HttpStatus;
+import org.springframework.stereotype.Component;
+import org.springframework.web.reactive.function.server.ServerRequest;
+import org.springframework.web.reactive.function.server.ServerResponse;
+import reactor.core.publisher.Mono;
+
+@Component
+public class Handler4 {
+
+public Mono<ServerResponse> handleRequest4(ServerRequest request) {
+    return ServerResponse.ok()
+        .body(sayHello(request)
+            .onErrorResume(e -> 
+                    Mono.error(new NameRequiredException(
+                        HttpStatus.BAD_REQUEST, "please provide a name", e))), String.class);
+}
+
+    private Mono<String> sayHello(ServerRequest request) {
+        try {
+            return Mono.just("Hello, " + request.queryParam("name").get());
+        } catch (Exception e) {
+            return Mono.error(e);
+        }
+    }
+
+}

spring-5-reactive/src/main/java/com/baeldung/reactive/errorhandling/handlers/Handler5.java

@@ -0,0 +1,22 @@
+
+package com.baeldung.reactive.errorhandling.handlers;
+
+import org.springframework.stereotype.Component;
+import org.springframework.web.reactive.function.server.ServerRequest;
+import org.springframework.web.reactive.function.server.ServerResponse;
+import reactor.core.publisher.Mono;
+
+@Component
+public class Handler5 {
+
+    public Mono<ServerResponse> handleRequest5(ServerRequest request) {
+        return ServerResponse.ok()
+            .body(sayHello(request), String.class);
+        
+    }
+
+    private Mono<String> sayHello(ServerRequest request) {
+            return Mono.just("Hello, " + request.queryParam("name").get());
+    }
+
+}

spring-5-reactive/src/main/java/com/baeldung/reactive/errorhandling/routers/Router1.java

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+
+package com.baeldung.reactive.errorhandling.routers;
+
+import com.baeldung.reactive.errorhandling.handlers.Handler1;
+import org.springframework.context.annotation.Bean;
+import org.springframework.http.MediaType;
+import org.springframework.stereotype.Component;
+import org.springframework.web.reactive.function.server.RequestPredicates;
+import org.springframework.web.reactive.function.server.RouterFunction;
+import org.springframework.web.reactive.function.server.RouterFunctions;
+import org.springframework.web.reactive.function.server.ServerResponse;
+
+@Component
+public class Router1 {
+
+    @Bean
+    public RouterFunction<ServerResponse> routeRequest1(Handler1 handler) {
+        return RouterFunctions.route(RequestPredicates.GET("/api/endpoint1")
+            .and(RequestPredicates.accept(MediaType.TEXT_PLAIN)), handler::handleRequest1);
+    }
+
+}

spring-5-reactive/src/main/java/com/baeldung/reactive/errorhandling/routers/Router2.java

@@ -0,0 +1,22 @@
+
+package com.baeldung.reactive.errorhandling.routers;
+
+import com.baeldung.reactive.errorhandling.handlers.Handler2;
+import org.springframework.context.annotation.Bean;
+import org.springframework.http.MediaType;
+import org.springframework.stereotype.Component;
+import org.springframework.web.reactive.function.server.RequestPredicates;
+import org.springframework.web.reactive.function.server.RouterFunction;
+import org.springframework.web.reactive.function.server.RouterFunctions;
+import org.springframework.web.reactive.function.server.ServerResponse;
+
+@Component
+public class Router2 {
+
+    @Bean
+    public RouterFunction<ServerResponse> routeRequest2(Handler2 handler) {
+        return RouterFunctions.route(RequestPredicates.GET("/api/endpoint2")
+            .and(RequestPredicates.accept(MediaType.TEXT_PLAIN)), handler::handleRequest2);
+    }
+
+}

spring-5-reactive/src/main/java/com/baeldung/reactive/errorhandling/routers/Router3.java

@@ -0,0 +1,22 @@
+
+package com.baeldung.reactive.errorhandling.routers;
+
+import com.baeldung.reactive.errorhandling.handlers.Handler3;
+import org.springframework.context.annotation.Bean;
+import org.springframework.http.MediaType;
+import org.springframework.stereotype.Component;
+import org.springframework.web.reactive.function.server.RequestPredicates;
+import org.springframework.web.reactive.function.server.RouterFunction;
+import org.springframework.web.reactive.function.server.RouterFunctions;
+import org.springframework.web.reactive.function.server.ServerResponse;
+
+@Component
+public class Router3 {
+
+    @Bean
+    public RouterFunction<ServerResponse> routeRequest3(Handler3 handler) {
+        return RouterFunctions.route(RequestPredicates.GET("/api/endpoint3")
+            .and(RequestPredicates.accept(MediaType.TEXT_PLAIN)), handler::handleRequest3);
+    }
+
+}

spring-5-reactive/src/main/java/com/baeldung/reactive/errorhandling/routers/Router4.java

@@ -0,0 +1,22 @@
+
+package com.baeldung.reactive.errorhandling.routers;
+
+import com.baeldung.reactive.errorhandling.handlers.Handler4;
+import org.springframework.context.annotation.Bean;
+import org.springframework.http.MediaType;
+import org.springframework.stereotype.Component;
+import org.springframework.web.reactive.function.server.RequestPredicates;
+import org.springframework.web.reactive.function.server.RouterFunction;
+import org.springframework.web.reactive.function.server.RouterFunctions;
+import org.springframework.web.reactive.function.server.ServerResponse;
+
+@Component
+public class Router4 {
+
+    @Bean
+    public RouterFunction<ServerResponse> routeRequest4(Handler4 handler) {
+        return RouterFunctions.route(RequestPredicates.GET("/api/endpoint4")
+            .and(RequestPredicates.accept(MediaType.TEXT_PLAIN)), handler::handleRequest4);
+    }
+
+}

spring-5-reactive/src/main/java/com/baeldung/reactive/errorhandling/routers/Router5.java

@@ -0,0 +1,22 @@
+
+package com.baeldung.reactive.errorhandling.routers;
+
+import com.baeldung.reactive.errorhandling.handlers.Handler5;
+import org.springframework.context.annotation.Bean;
+import org.springframework.http.MediaType;
+import org.springframework.stereotype.Component;
+import org.springframework.web.reactive.function.server.RequestPredicates;
+import org.springframework.web.reactive.function.server.RouterFunction;
+import org.springframework.web.reactive.function.server.RouterFunctions;
+import org.springframework.web.reactive.function.server.ServerResponse;
+
+@Component
+public class Router5 {
+
+    @Bean
+    public RouterFunction<ServerResponse> routeRequest5(Handler5 handler) {
+        return RouterFunctions.route(RequestPredicates.GET("/api/endpoint5")
+            .and(RequestPredicates.accept(MediaType.TEXT_PLAIN)), handler::handleRequest5);
+    }
+
+}

spring-5-reactive/src/test/java/com/baeldung/reactive/errorhandling/ErrorHandlingTest.java

@@ -0,0 +1,179 @@
+/*
+ * To change this license header, choose License Headers in Project Properties.
+ * To change this template file, choose Tools | Templates
+ * and open the template in the editor.
+ */
+package com.baeldung.reactive.errorhandling;
+
+import java.io.IOException;
+import static org.junit.Assert.assertEquals;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.boot.test.context.SpringBootTest.WebEnvironment;
+import org.springframework.http.MediaType;
+import org.springframework.test.context.junit4.SpringRunner;
+import org.springframework.test.web.reactive.server.WebTestClient;
+
+@RunWith(SpringRunner.class)
+@SpringBootTest(webEnvironment = WebEnvironment.DEFINED_PORT)
+public class ErrorHandlingTest {
+
+    @Autowired
+    private WebTestClient webTestClient;
+
+    @Test
+    public void testLocalErrorHandlingUsingOnErrorReturn() throws IOException {
+
+        System.out.println("Testing local error handling using onErrorReturn");
+
+        // Pass a username
+        String i = webTestClient.get()
+            .uri("/api/endpoint1?name={username}", "Tony")
+            .accept(MediaType.TEXT_PLAIN)
+            .exchange()
+            .returnResult(String.class)
+            .getResponseBody()
+            .blockFirst();
+
+        assertEquals("Hello, Tony", i);
+
+        // Do not pass a username
+        i = webTestClient.get()
+            .uri("/api/endpoint1")
+            .accept(MediaType.TEXT_PLAIN)
+            .exchange()
+            .returnResult(String.class)
+            .getResponseBody()
+            .blockFirst();
+
+        assertEquals("Hello, Stranger", i);
+
+    }
+
+    @Test
+    public void testLocalErrorHandlingUsingOnErrorResumeWithFallback() throws IOException {
+
+        System.out.println("Testing local error handling using onErrorResume with fallback");
+
+        // Pass a username
+        String i = webTestClient.get()
+            .uri("/api/endpoint2?name={username}", "Tony")
+            .accept(MediaType.TEXT_PLAIN)
+            .exchange()
+            .returnResult(String.class)
+            .getResponseBody()
+            .blockFirst();
+
+        assertEquals("Hello, Tony", i);
+
+        // Do not pass a username
+        i = webTestClient.get()
+            .uri("/api/endpoint2")
+            .accept(MediaType.TEXT_PLAIN)
+            .exchange()
+            .returnResult(String.class)
+            .getResponseBody()
+            .blockFirst();
+
+        assertEquals("Hello, Stranger", i);
+
+    }
+
+    @Test
+    public void testLocalErrorHandlingUsingOnErrorResumeWithDynamicFallbackValue() throws IOException {
+
+        System.out.println("Testing local error handling using onErrorResume with dynamic fallback value");
+
+        // Pass a username
+        String i = webTestClient.get()
+            .uri("/api/endpoint3?name={username}", "Tony")
+            .accept(MediaType.TEXT_PLAIN)
+            .exchange()
+            .returnResult(String.class)
+            .getResponseBody()
+            .blockFirst();
+
+        assertEquals("Hello, Tony", i);
+
+        // Do not pass a username
+        i = webTestClient.get()
+            .uri("/api/endpoint3")
+            .accept(MediaType.TEXT_PLAIN)
+            .exchange()
+            .returnResult(String.class)
+            .getResponseBody()
+            .blockFirst();
+
+        assertEquals("Hi, I looked around for your name but found: No value present", i);
+
+    }
+    
+    @Test
+    public void testLocalErrorHandlingUsingOnErrorResumeWithCatchAndRethrow() throws IOException {
+
+        System.out.println("Testing local error handling using onErrorResume with catch and rethrow");
+
+        // Pass a username
+        String i = webTestClient.get()
+            .uri("/api/endpoint4?name={username}", "Tony")
+            .accept(MediaType.TEXT_PLAIN)
+            .exchange()
+            .returnResult(String.class)
+            .getResponseBody()
+            .blockFirst();
+
+        assertEquals("Hello, Tony", i);
+
+        // Do not pass a username
+        webTestClient.get()
+            .uri("/api/endpoint4")
+            .accept(MediaType.TEXT_PLAIN)
+            .exchange()
+            .expectStatus()
+            .isBadRequest()
+            .expectHeader()
+            .contentType(MediaType.APPLICATION_JSON_UTF8)
+            .expectBody()
+            .jsonPath("$.message")
+            .isNotEmpty()
+            .jsonPath("$.message")
+            .isEqualTo("please provide a name");
+
+    }
+        
+    @Test
+    public void testGlobalErrorHandlingUsingErrorWebExceptionHandler() throws IOException {
+
+        System.out.println("Testing local error handling using ErrorWebExceptionHandler");
+
+        // Pass a username
+        String i = webTestClient.get()
+            .uri("/api/endpoint5?name={username}", "Tony")
+            .accept(MediaType.TEXT_PLAIN)
+            .exchange()
+            .returnResult(String.class)
+            .getResponseBody()
+            .blockFirst();
+
+        assertEquals("Hello, Tony", i);
+
+        // Do not pass a username
+        webTestClient.get()
+            .uri("/api/endpoint5")
+            .accept(MediaType.TEXT_PLAIN)
+            .exchange()
+            .expectStatus()
+            .isBadRequest()
+            .expectHeader()
+            .contentType(MediaType.APPLICATION_JSON_UTF8)
+            .expectBody()
+            .jsonPath("$.message")
+            .isNotEmpty()
+            .jsonPath("$.message")
+            .isEqualTo("please provide a name");
+
+    }
+            
+}

spring-5-reactive/src/test/java/com/baeldung/reactive/errorhandling/ErrorHandlingTest.java~

@@ -0,0 +1,179 @@
+/*
+ * To change this license header, choose License Headers in Project Properties.
+ * To change this template file, choose Tools | Templates
+ * and open the template in the editor.
+ */
+package com.baeldung.reactive.errorhandling;
+
+import java.io.IOException;
+import static org.junit.Assert.assertEquals;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.boot.test.context.SpringBootTest.WebEnvironment;
+import org.springframework.http.MediaType;
+import org.springframework.test.context.junit4.SpringRunner;
+import org.springframework.test.web.reactive.server.WebTestClient;
+
+@RunWith(SpringRunner.class)
+@SpringBootTest(webEnvironment = WebEnvironment.DEFINED_PORT)
+public class ApplicationTest {
+
+    @Autowired
+    private WebTestClient webTestClient;
+
+    @Test
+    public void testLocalErrorHandlingUsingOnErrorReturn() throws IOException {
+
+        System.out.println("Testing local error handling using onErrorReturn");
+
+        // Pass a username
+        String i = webTestClient.get()
+            .uri("/api/endpoint1?name={username}", "Tony")
+            .accept(MediaType.TEXT_PLAIN)
+            .exchange()
+            .returnResult(String.class)
+            .getResponseBody()
+            .blockFirst();
+
+        assertEquals("Hello, Tony", i);
+
+        // Do not pass a username
+        i = webTestClient.get()
+            .uri("/api/endpoint1")
+            .accept(MediaType.TEXT_PLAIN)
+            .exchange()
+            .returnResult(String.class)
+            .getResponseBody()
+            .blockFirst();
+
+        assertEquals("Hello, Stranger", i);
+
+    }
+
+    @Test
+    public void testLocalErrorHandlingUsingOnErrorResumeWithFallback() throws IOException {
+
+        System.out.println("Testing local error handling using onErrorResume with fallback");
+
+        // Pass a username
+        String i = webTestClient.get()
+            .uri("/api/endpoint2?name={username}", "Tony")
+            .accept(MediaType.TEXT_PLAIN)
+            .exchange()
+            .returnResult(String.class)
+            .getResponseBody()
+            .blockFirst();
+
+        assertEquals("Hello, Tony", i);
+
+        // Do not pass a username
+        i = webTestClient.get()
+            .uri("/api/endpoint2")
+            .accept(MediaType.TEXT_PLAIN)
+            .exchange()
+            .returnResult(String.class)
+            .getResponseBody()
+            .blockFirst();
+
+        assertEquals("Hello, Stranger", i);
+
+    }
+
+    @Test
+    public void testLocalErrorHandlingUsingOnErrorResumeWithDynamicFallbackValue() throws IOException {
+
+        System.out.println("Testing local error handling using onErrorResume with dynamic fallback value");
+
+        // Pass a username
+        String i = webTestClient.get()
+            .uri("/api/endpoint3?name={username}", "Tony")
+            .accept(MediaType.TEXT_PLAIN)
+            .exchange()
+            .returnResult(String.class)
+            .getResponseBody()
+            .blockFirst();
+
+        assertEquals("Hello, Tony", i);
+
+        // Do not pass a username
+        i = webTestClient.get()
+            .uri("/api/endpoint3")
+            .accept(MediaType.TEXT_PLAIN)
+            .exchange()
+            .returnResult(String.class)
+            .getResponseBody()
+            .blockFirst();
+
+        assertEquals("Hi, I looked around for your name but found: No value present", i);
+
+    }
+    
+    @Test
+    public void testLocalErrorHandlingUsingOnErrorResumeWithCatchAndRethrow() throws IOException {
+
+        System.out.println("Testing local error handling using onErrorResume with catch and rethrow");
+
+        // Pass a username
+        String i = webTestClient.get()
+            .uri("/api/endpoint4?name={username}", "Tony")
+            .accept(MediaType.TEXT_PLAIN)
+            .exchange()
+            .returnResult(String.class)
+            .getResponseBody()
+            .blockFirst();
+
+        assertEquals("Hello, Tony", i);
+
+        // Do not pass a username
+        webTestClient.get()
+            .uri("/api/endpoint4")
+            .accept(MediaType.TEXT_PLAIN)
+            .exchange()
+            .expectStatus()
+            .isBadRequest()
+            .expectHeader()
+            .contentType(MediaType.APPLICATION_JSON_UTF8)
+            .expectBody()
+            .jsonPath("$.message")
+            .isNotEmpty()
+            .jsonPath("$.message")
+            .isEqualTo("please provide a name");
+
+    }
+        
+    @Test
+    public void testGlobalErrorHandlingUsingErrorWebExceptionHandler() throws IOException {
+
+        System.out.println("Testing local error handling using ErrorWebExceptionHandler");
+
+        // Pass a username
+        String i = webTestClient.get()
+            .uri("/api/endpoint5?name={username}", "Tony")
+            .accept(MediaType.TEXT_PLAIN)
+            .exchange()
+            .returnResult(String.class)
+            .getResponseBody()
+            .blockFirst();
+
+        assertEquals("Hello, Tony", i);
+
+        // Do not pass a username
+        webTestClient.get()
+            .uri("/api/endpoint5")
+            .accept(MediaType.TEXT_PLAIN)
+            .exchange()
+            .expectStatus()
+            .isBadRequest()
+            .expectHeader()
+            .contentType(MediaType.APPLICATION_JSON_UTF8)
+            .expectBody()
+            .jsonPath("$.message")
+            .isNotEmpty()
+            .jsonPath("$.message")
+            .isEqualTo("please provide a name");
+
+    }
+            
+}