Merge pull request #15702 from balasr21/master

BAEL-7272: Added code for custom deserialization using Spring WebClient

spring-reactive-modules/spring-reactive-3/pom.xml

@@ -64,6 +64,11 @@
             <groupId>org.springframework.session</groupId>
             <artifactId>spring-session-data-redis</artifactId>
         </dependency>
+        <dependency>
+            <groupId>com.squareup.okhttp3</groupId>
+            <artifactId>mockwebserver</artifactId>
+            <version>4.12.0</version>
+        </dependency>
     </dependencies>
 
     <dependencyManagement>

spring-reactive-modules/spring-reactive-3/src/main/java/com/baeldung/custom/deserialization/Application.java

@@ -0,0 +1,13 @@
+package com.baeldung.custom.deserialization;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+
+@SpringBootApplication
+public class Application {
+
+    public static void main(String[] args) {
+        SpringApplication.run(Application.class, args);
+    }
+
+}

spring-reactive-modules/spring-reactive-3/src/main/java/com/baeldung/custom/deserialization/config/CodecCustomizerConfig.java

@@ -0,0 +1,27 @@
+package com.baeldung.custom.deserialization.config;
+
+import org.springframework.boot.web.codec.CodecCustomizer;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.http.MediaType;
+import org.springframework.http.codec.CodecConfigurer;
+import org.springframework.http.codec.json.Jackson2JsonDecoder;
+import org.springframework.http.codec.json.Jackson2JsonEncoder;
+import org.springframework.util.MimeType;
+
+import com.fasterxml.jackson.databind.ObjectMapper;
+
+@Configuration
+public class CodecCustomizerConfig {
+
+    @Bean
+    public CodecCustomizer codecCustomizer(ObjectMapper customObjectMapper) {
+        return configurer -> {
+            MimeType mimeType = MimeType.valueOf(MediaType.APPLICATION_JSON_VALUE);
+            CodecConfigurer.CustomCodecs customCodecs = configurer.customCodecs();
+            customCodecs.register(new Jackson2JsonDecoder(customObjectMapper, mimeType));
+            customCodecs.register(new Jackson2JsonEncoder(customObjectMapper, mimeType));
+        };
+    }
+
+}

spring-reactive-modules/spring-reactive-3/src/main/java/com/baeldung/custom/deserialization/config/CustomDeserializer.java

@@ -0,0 +1,21 @@
+package com.baeldung.custom.deserialization.config;
+
+import java.io.IOException;
+import java.time.LocalDateTime;
+import java.time.OffsetDateTime;
+import java.time.ZoneOffset;
+
+import com.fasterxml.jackson.core.JsonParser;
+import com.fasterxml.jackson.databind.DeserializationContext;
+import com.fasterxml.jackson.datatype.jsr310.deser.LocalDateTimeDeserializer;
+
+public class CustomDeserializer extends LocalDateTimeDeserializer {
+    @Override
+    public LocalDateTime deserialize(JsonParser jsonParser, DeserializationContext ctxt) throws IOException {
+        try {
+            return OffsetDateTime.parse(jsonParser.getText()).atZoneSameInstant(ZoneOffset.UTC).toLocalDateTime();
+        } catch (Exception e) {
+            return super.deserialize(jsonParser, ctxt);
+        }
+    }
+}

spring-reactive-modules/spring-reactive-3/src/main/java/com/baeldung/custom/deserialization/config/CustomObjectMapper.java

@@ -0,0 +1,18 @@
+package com.baeldung.custom.deserialization.config;
+
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+
+import com.fasterxml.jackson.databind.DeserializationFeature;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.fasterxml.jackson.datatype.jsr310.JavaTimeModule;
+
+@Configuration
+public class CustomObjectMapper {
+    @Bean
+    public ObjectMapper objectMapper() {
+        return new ObjectMapper()
+            .configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, true)
+            .registerModule(new JavaTimeModule());
+    }
+}

spring-reactive-modules/spring-reactive-3/src/main/java/com/baeldung/custom/deserialization/controller/OrderController.java

@@ -0,0 +1,37 @@
+package com.baeldung.custom.deserialization.controller;
+
+import org.springframework.http.MediaType;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.PathVariable;
+import org.springframework.web.bind.annotation.RestController;
+
+import com.baeldung.custom.deserialization.model.OrderResponse;
+import com.baeldung.custom.deserialization.service.ExternalServiceV1;
+import com.baeldung.custom.deserialization.service.ExternalServiceV2;
+
+import reactor.core.publisher.Mono;
+
+@RestController
+public class OrderController {
+
+    private final ExternalServiceV1 externalServiceV1;
+    private final ExternalServiceV2 externalServiceV2;
+
+    public OrderController(ExternalServiceV1 externalServiceV1, ExternalServiceV2 externalServiceV2) {
+        this.externalServiceV1 = externalServiceV1;
+        this.externalServiceV2 = externalServiceV2;
+    }
+
+    @GetMapping(value = "v1/order/{id}", produces = MediaType.APPLICATION_JSON_VALUE)
+    public final Mono<OrderResponse> searchOrderV1(@PathVariable(value = "id") int id) {
+        return externalServiceV1.findById(id)
+            .bodyToMono(OrderResponse.class);
+    }
+
+    @GetMapping(value = "v2/order/{id}", produces = MediaType.APPLICATION_JSON_VALUE)
+    public final Mono<OrderResponse> searchOrderV2(@PathVariable(value = "id") int id) {
+        return externalServiceV2.findById(id)
+            .bodyToMono(OrderResponse.class);
+    }
+
+}

spring-reactive-modules/spring-reactive-3/src/main/java/com/baeldung/custom/deserialization/model/OrderResponse.java

@@ -0,0 +1,19 @@
+package com.baeldung.custom.deserialization.model;
+
+import java.time.LocalDateTime;
+import java.util.List;
+import java.util.UUID;
+
+import lombok.Data;
+
+@Data
+public class OrderResponse {
+
+    private UUID orderId;
+
+    private LocalDateTime orderDateTime;
+
+    private List<String> address;
+
+    private List<String> orderNotes;
+}

spring-reactive-modules/spring-reactive-3/src/main/java/com/baeldung/custom/deserialization/service/ExternalServiceV1.java

@@ -0,0 +1,23 @@
+package com.baeldung.custom.deserialization.service;
+
+import org.springframework.stereotype.Component;
+import org.springframework.web.reactive.function.client.WebClient;
+
+@Component
+public class ExternalServiceV1 {
+
+    private final WebClient.Builder webclientBuilder;
+
+    public ExternalServiceV1(WebClient.Builder webclientBuilder) {
+        this.webclientBuilder = webclientBuilder;
+    }
+
+    public WebClient.ResponseSpec findById(int id) {
+        return webclientBuilder.baseUrl("http://localhost:8090/")
+            .build()
+            .get()
+            .uri("external/order/" + id)
+            .retrieve();
+    }
+
+}

spring-reactive-modules/spring-reactive-3/src/main/java/com/baeldung/custom/deserialization/service/ExternalServiceV2.java

@@ -0,0 +1,40 @@
+package com.baeldung.custom.deserialization.service;
+
+import java.time.LocalDateTime;
+
+import org.springframework.http.MediaType;
+import org.springframework.http.codec.json.Jackson2JsonDecoder;
+import org.springframework.http.codec.json.Jackson2JsonEncoder;
+import org.springframework.stereotype.Component;
+import org.springframework.web.reactive.function.client.ExchangeStrategies;
+import org.springframework.web.reactive.function.client.WebClient;
+
+import com.baeldung.custom.deserialization.config.CustomDeserializer;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.fasterxml.jackson.databind.module.SimpleModule;
+
+@Component
+public class ExternalServiceV2 {
+
+    public WebClient.ResponseSpec findById(int id) {
+
+        ObjectMapper objectMapper = new ObjectMapper().registerModule(new SimpleModule().addDeserializer(LocalDateTime.class, new CustomDeserializer()));
+
+        WebClient webClient = WebClient.builder()
+            .baseUrl("http://localhost:8090/")
+            .exchangeStrategies(ExchangeStrategies.builder()
+                .codecs(clientDefaultCodecsConfigurer -> {
+                    clientDefaultCodecsConfigurer.defaultCodecs()
+                        .jackson2JsonEncoder(new Jackson2JsonEncoder(objectMapper, MediaType.APPLICATION_JSON));
+                    clientDefaultCodecsConfigurer.defaultCodecs()
+                        .jackson2JsonDecoder(new Jackson2JsonDecoder(objectMapper, MediaType.APPLICATION_JSON));
+                })
+                .build())
+            .build();
+
+        return webClient.get()
+            .uri("external/order/" + id)
+            .retrieve();
+    }
+
+}

spring-reactive-modules/spring-reactive-3/src/test/java/com/baeldung/custom/deserialization/OrderControllerIntegrationTest.java

@@ -0,0 +1,135 @@
+package com.baeldung.custom.deserialization;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+import java.io.IOException;
+import java.time.LocalDateTime;
+import java.util.UUID;
+
+import org.junit.jupiter.api.AfterAll;
+import org.junit.jupiter.api.BeforeAll;
+import org.junit.jupiter.api.Test;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.autoconfigure.web.reactive.AutoConfigureWebTestClient;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.http.HttpStatus;
+import org.springframework.test.context.TestPropertySource;
+import org.springframework.test.web.reactive.server.WebTestClient;
+
+import com.baeldung.custom.deserialization.model.OrderResponse;
+
+import okhttp3.mockwebserver.MockResponse;
+import okhttp3.mockwebserver.MockWebServer;
+
+@SpringBootTest(classes = Application.class, webEnvironment = SpringBootTest.WebEnvironment.DEFINED_PORT)
+@TestPropertySource(properties = "server.port=8091")
+@AutoConfigureWebTestClient(timeout = "100000")
+class OrderControllerIntegrationTest {
+
+    @Autowired
+    private WebTestClient webTestClient;
+
+    private static MockWebServer mockExternalService;
+
+    @BeforeAll
+    static void setup() throws IOException {
+        mockExternalService = new MockWebServer();
+        mockExternalService.start(8090);
+    }
+
+    @Test
+    void givenMockedExternalResponse_whenSearchByIdV1_thenOrderResponseShouldFailBecauseOfUnknownProperty() {
+
+        mockExternalService.enqueue(new MockResponse().addHeader("Content-Type", "application/json; charset=utf-8")
+            .setBody("{\n" + "                      \"orderId\": \"a1b2c3d4-e5f6-4a5b-8c9d-0123456789ab\",\n"
+                + "                      \"orderDateTime\": \"2024-01-20T12:34:56\",\n"
+                + "                      \"address\": [\"123 Main St\", \"Apt 456\", \"Cityville\"],\n"
+                + "                      \"orderNotes\": [\"Special request: Handle with care\", \"Gift wrapping required\"],\n"
+                + "                      \"customerName\": \"John Doe\",\n" + "                      \"totalAmount\": 99.99,\n"
+                + "                      \"paymentMethod\": \"Credit Card\"\n" + "                    }")
+            .setResponseCode(HttpStatus.OK.value()));
+
+        webTestClient.get()
+            .uri("v1/order/1")
+            .exchange()
+            .expectStatus()
+            .is5xxServerError();
+    }
+
+    @Test
+    void givenMockedExternalResponse_whenSearchByIdV1_thenOrderResponseShouldBeReceivedSuccessfully() {
+
+        mockExternalService.enqueue(new MockResponse().addHeader("Content-Type", "application/json; charset=utf-8")
+            .setBody("{\n" + "                  \"orderId\": \"a1b2c3d4-e5f6-4a5b-8c9d-0123456789ab\",\n"
+                + "                  \"orderDateTime\": \"2024-01-20T12:34:56\",\n"
+                + "                  \"address\": [\"123 Main St\", \"Apt 456\", \"Cityville\"],\n"
+                + "                  \"orderNotes\": [\"Special request: Handle with care\", \"Gift wrapping required\"]\n"
+                + "                }")
+            .setResponseCode(HttpStatus.OK.value()));
+
+        OrderResponse orderResponse = webTestClient.get()
+            .uri("v1/order/1")
+            .exchange()
+            .expectStatus()
+            .isOk()
+            .expectBody(OrderResponse.class)
+            .returnResult()
+            .getResponseBody();
+        assertEquals(UUID.fromString("a1b2c3d4-e5f6-4a5b-8c9d-0123456789ab"), orderResponse.getOrderId());
+        assertEquals(LocalDateTime.of(2024, 1, 20, 12, 34, 56), orderResponse.getOrderDateTime());
+        assertThat(orderResponse.getAddress()).hasSize(3);
+        assertThat(orderResponse.getOrderNotes()).hasSize(2);
+    }
+
+    @Test
+    void givenMockedExternalResponse_whenSearchByIdV2_thenOrderResponseShouldFailBecauseOfUnknownProperty() {
+
+        mockExternalService.enqueue(new MockResponse().addHeader("Content-Type", "application/json; charset=utf-8")
+            .setBody("{\n" + "                  \"orderId\": \"a1b2c3d4-e5f6-4a5b-8c9d-0123456789ab\",\n"
+                + "                  \"orderDateTime\": \"2024-01-20T12:34:56\",\n"
+                + "                  \"address\": [\"123 Main St\", \"Apt 456\", \"Cityville\"],\n"
+                + "                  \"orderNotes\": [\"Special request: Handle with care\", \"Gift wrapping required\"],\n"
+                + "                  \"customerName\": \"John Doe\",\n"
+                + "                  \"totalAmount\": 99.99,\n"
+                + "                  \"paymentMethod\": \"Credit Card\"\n"
+                + "                }")
+            .setResponseCode(HttpStatus.OK.value()));
+
+        webTestClient.get()
+            .uri("v2/order/1")
+            .exchange()
+            .expectStatus()
+            .is5xxServerError();
+    }
+
+    @Test
+    void givenMockedExternalResponse_whenSearchByIdV2_thenOrderResponseShouldBeReceivedSuccessfully() {
+
+        mockExternalService.enqueue(new MockResponse().addHeader("Content-Type", "application/json; charset=utf-8")
+            .setBody("{\n" + "                  \"orderId\": \"a1b2c3d4-e5f6-4a5b-8c9d-0123456789ab\",\n"
+                + "                  \"orderDateTime\": \"2024-01-20T14:34:56+01:00\",\n"
+                + "                  \"address\": [\"123 Main St\", \"Apt 456\", \"Cityville\"],\n"
+                + "                  \"orderNotes\": [\"Special request: Handle with care\", \"Gift wrapping required\"]\n" + "                }")
+            .setResponseCode(HttpStatus.OK.value()));
+
+        OrderResponse orderResponse = webTestClient.get()
+            .uri("v2/order/1")
+            .exchange()
+            .expectStatus()
+            .isOk()
+            .expectBody(OrderResponse.class)
+            .returnResult()
+            .getResponseBody();
+        assertEquals(UUID.fromString("a1b2c3d4-e5f6-4a5b-8c9d-0123456789ab"), orderResponse.getOrderId());
+        assertEquals(LocalDateTime.of(2024, 1, 20, 13, 34, 56), orderResponse.getOrderDateTime());
+        assertThat(orderResponse.getAddress()).hasSize(3);
+        assertThat(orderResponse.getOrderNotes()).hasSize(2);
+    }
+
+    @AfterAll
+    static void tearDown() throws IOException {
+        mockExternalService.shutdown();
+    }
+
+}