Bael 5961: OpenTelemetry integration with Spring Boot application (#13252)

* Open telemetry in spring boot

* Removed unused field

* Test add and seperate packages

* Refactored code

* Version moved to property

* Removed unused logback files

* update version in docker file

* corrected spacing

* COde review refactoring

* COde review refactoring

* COde review refactoring

* corrected property

* PostContruct add on repo setup

* corrected var names

* change to junit 5 and other improvements

* Port reverted back

* Code review implement

* Logger update

* Logger var update

---------

Co-authored-by: Saikat <saikatcse03y@gmail.com>

spring-cloud-modules/pom.xml

@@ -55,6 +55,7 @@
         <module>spring-cloud-data-flow</module>
         <module>spring-cloud-sleuth</module>
         <module>spring-cloud-openfeign-2</module>
+	<module>spring-cloud-open-telemetry</module>
     </modules>
 
     <build>

spring-cloud-modules/spring-cloud-open-telemetry/docker-compose.yml

@@ -0,0 +1,30 @@
+version: "4.0"
+
+services:
+  product-service:
+    platform: linux/x86_64
+    build: spring-cloud-open-telemetry1/
+    ports:
+      - "8080:8080"
+
+  price-service:
+    platform: linux/x86_64
+    build: spring-cloud-open-telemetry2/
+    ports:
+      - "8081"
+
+  jaeger-service:
+    image: jaegertracing/all-in-one:latest
+    ports:
+      - "16686:16686"
+      - "14250"
+
+  collector:
+    image: otel/opentelemetry-collector:0.47.0
+    command: [ "--config=/etc/otel-collector-config.yml" ]
+    volumes:
+      - ./otel-config.yml:/etc/otel-collector-config.yml
+    ports:
+      - "4317:4317"
+    depends_on:
+      - jaeger-service

spring-cloud-modules/spring-cloud-open-telemetry/otel-config.yml

@@ -0,0 +1,23 @@
+receivers:
+  otlp:
+    protocols:
+      grpc:
+      http:
+
+processors:
+  batch:
+
+exporters:
+  logging:
+    logLevel: debug
+  jaeger:
+    endpoint: jaeger-service:14250
+    tls:
+      insecure: true
+
+service:
+  pipelines:
+    traces:
+      receivers: [ otlp ]
+      processors: [ batch ]
+      exporters: [ logging, jaeger ]

spring-cloud-modules/spring-cloud-open-telemetry/pom.xml

@@ -0,0 +1,22 @@
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+    <groupId>com.baeldung.spring.cloud</groupId>
+    <artifactId>spring-cloud-open-telemetry</artifactId>
+    <version>1.0.0-SNAPSHOT</version>
+    <name>spring-cloud-open-telemetry</name>
+    <packaging>pom</packaging>
+
+    <parent>
+        <groupId>com.baeldung.spring.cloud</groupId>
+        <artifactId>spring-cloud-modules</artifactId>
+        <version>1.0.0-SNAPSHOT</version>
+    </parent>
+
+    <modules>
+        <module>spring-cloud-open-telemetry1</module>
+        <module>spring-cloud-open-telemetry2</module>
+    </modules>
+
+</project>

spring-cloud-modules/spring-cloud-open-telemetry/spring-cloud-open-telemetry1/Dockerfile

@@ -0,0 +1,7 @@
+FROM adoptopenjdk/openjdk11:alpine
+
+COPY target/spring-cloud-open-telemetry1-1.0.0-SNAPSHOT.jar spring-cloud-open-telemetry.jar
+
+EXPOSE 8081
+
+ENTRYPOINT ["java","-jar","/spring-cloud-open-telemetry.jar"]

spring-cloud-modules/spring-cloud-open-telemetry/spring-cloud-open-telemetry1/pom.xml

@@ -0,0 +1,116 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+    <artifactId>spring-cloud-open-telemetry1</artifactId>
+    <groupId>com.baeldung.spring.cloud</groupId>
+    <version>1.0.0-SNAPSHOT</version>
+    <name>spring-cloud-open-telemetry1</name>
+    <packaging>jar</packaging>
+
+    <parent>
+        <groupId>com.baeldung.spring.cloud</groupId>
+        <artifactId>spring-cloud-open-telemetry</artifactId>
+        <version>1.0.0-SNAPSHOT</version>
+    </parent>
+
+    <dependencyManagement>
+        <dependencies>
+            <dependency>
+                <groupId>org.springframework.boot</groupId>
+                <artifactId>spring-boot-dependencies</artifactId>
+                <version>${spring-boot-dependencies.version}</version>
+                <type>pom</type>
+                <scope>import</scope>
+            </dependency>
+            <dependency>
+                <groupId>org.springframework.cloud</groupId>
+                <artifactId>spring-cloud-dependencies</artifactId>
+                <version>${release.train.version}</version>
+                <type>pom</type>
+                <scope>import</scope>
+            </dependency>
+            <dependency>
+                <groupId>org.springframework.cloud</groupId>
+                <artifactId>spring-cloud-sleuth-otel-dependencies</artifactId>
+                <version>${spring-cloud-sleuth-otel.version}</version>
+                <scope>import</scope>
+                <type>pom</type>
+            </dependency>
+        </dependencies>
+    </dependencyManagement>
+
+    <dependencies>
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-starter-web</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>org.springframework.cloud</groupId>
+            <artifactId>spring-cloud-starter-sleuth</artifactId>
+            <exclusions>
+                <exclusion>
+                    <groupId>org.springframework.cloud</groupId>
+                    <artifactId>spring-cloud-sleuth-brave</artifactId>
+                </exclusion>
+            </exclusions>
+        </dependency>
+        <dependency>
+            <groupId>org.springframework.cloud</groupId>
+            <artifactId>spring-cloud-sleuth-otel-autoconfigure</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>io.opentelemetry</groupId>
+            <artifactId>opentelemetry-exporter-otlp-trace</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>io.grpc</groupId>
+            <artifactId>grpc-okhttp</artifactId>
+            <version>${grpc-okhttp.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>org.junit.jupiter</groupId>
+            <artifactId>junit-jupiter-engine</artifactId>
+            <version>${junit-jupiter.version}</version>
+            <scope>test</scope>
+        </dependency>
+    </dependencies>
+
+    <build>
+        <plugins>
+            <plugin>
+                <groupId>org.springframework.boot</groupId>
+                <artifactId>spring-boot-maven-plugin</artifactId>
+                <executions>
+                    <execution>
+                        <goals>
+                            <goal>repackage</goal>
+                        </goals>
+                    </execution>
+                </executions>
+            </plugin>
+        </plugins>
+    </build>
+
+    <repositories>
+        <repository>
+            <id>spring-milestones</id>
+            <url>https://repo.spring.io/milestone</url>
+        </repository>
+    </repositories>
+    <pluginRepositories>
+        <pluginRepository>
+            <id>spring-milestones</id>
+            <url>https://repo.spring.io/milestone</url>
+        </pluginRepository>
+    </pluginRepositories>
+
+    <properties>
+        <spring-boot-dependencies.version>2.5.7</spring-boot-dependencies.version>
+        <release.train.version>2020.0.4</release.train.version>
+        <spring-cloud-sleuth-otel.version>1.0.0-M12</spring-cloud-sleuth-otel.version>
+        <grpc-okhttp.version>1.42.1</grpc-okhttp.version>
+    </properties>
+
+</project>

spring-cloud-modules/spring-cloud-open-telemetry/spring-cloud-open-telemetry1/src/main/java/com/baeldung/opentelemetry/ProductApplication.java

@@ -0,0 +1,12 @@
+package com.baeldung.opentelemetry;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+
+@SpringBootApplication
+public class ProductApplication {
+
+    public static void main(String[] args) {
+        SpringApplication.run(ProductApplication.class, args);
+    }
+}

spring-cloud-modules/spring-cloud-open-telemetry/spring-cloud-open-telemetry1/src/main/java/com/baeldung/opentelemetry/api/client/PriceClient.java

@@ -0,0 +1,34 @@
+package com.baeldung.opentelemetry.api.client;
+
+import com.baeldung.opentelemetry.model.Price;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.beans.factory.annotation.Value;
+import org.springframework.http.ResponseEntity;
+import org.springframework.stereotype.Component;
+import org.springframework.web.bind.annotation.PathVariable;
+import org.springframework.web.client.RestTemplate;
+
+@Component
+public class PriceClient {
+
+    private static final Logger LOGGER = LoggerFactory.getLogger(PriceClient.class);
+
+    private final RestTemplate restTemplate;
+
+    @Autowired
+    public PriceClient(RestTemplate restTemplate) {
+        this.restTemplate = restTemplate;
+    }
+
+    @Value("${priceClient.baseUrl}")
+    private String baseUrl;
+
+    public Price getPrice(@PathVariable("id") long productId){
+        LOGGER.info("Fetching Price Details With Product Id {}", productId);
+        String url = String.format("%s/price/%d", baseUrl, productId);
+        ResponseEntity<Price> price = restTemplate.getForEntity(url, Price.class);
+        return price.getBody();
+    }
+}

spring-cloud-modules/spring-cloud-open-telemetry/spring-cloud-open-telemetry1/src/main/java/com/baeldung/opentelemetry/configuration/RestConfiguration.java

@@ -0,0 +1,15 @@
+package com.baeldung.opentelemetry.configuration;
+
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.web.client.RestTemplate;
+
+@Configuration
+public class RestConfiguration {
+
+    @Bean
+    public RestTemplate restTemplate() {
+        return new RestTemplate();
+    }
+
+}

spring-cloud-modules/spring-cloud-open-telemetry/spring-cloud-open-telemetry1/src/main/java/com/baeldung/opentelemetry/controller/ProductController.java

@@ -0,0 +1,36 @@
+package com.baeldung.opentelemetry.controller;
+
+import com.baeldung.opentelemetry.api.client.PriceClient;
+import com.baeldung.opentelemetry.model.Product;
+import com.baeldung.opentelemetry.repository.ProductRepository;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.PathVariable;
+import org.springframework.web.bind.annotation.RestController;
+
+@RestController
+public class ProductController {
+
+    private static final Logger LOGGER = LoggerFactory.getLogger(ProductController.class);
+
+    private final PriceClient priceClient;
+
+    private final ProductRepository productRepository;
+
+    @Autowired
+    public ProductController(PriceClient priceClient, ProductRepository productRepository) {
+        this.priceClient = priceClient;
+        this.productRepository = productRepository;
+    }
+
+    @GetMapping(path = "/product/{id}")
+    public Product getProductDetails(@PathVariable("id") long productId){
+        LOGGER.info("Getting Product and Price Details With Product Id {}", productId);
+        Product product = productRepository.getProduct(productId);
+        product.setPrice(priceClient.getPrice(productId));
+
+        return product;
+    }
+}

spring-cloud-modules/spring-cloud-open-telemetry/spring-cloud-open-telemetry1/src/main/java/com/baeldung/opentelemetry/exception/ProductControllerAdvice.java

@@ -0,0 +1,22 @@
+package com.baeldung.opentelemetry.exception;
+
+import org.springframework.http.HttpStatus;
+import org.springframework.http.ResponseEntity;
+import org.springframework.web.bind.annotation.ExceptionHandler;
+import org.springframework.web.bind.annotation.RestControllerAdvice;
+import org.springframework.web.client.HttpServerErrorException;
+
+
+@RestControllerAdvice
+public class ProductControllerAdvice {
+
+    @ExceptionHandler(ProductNotFoundException.class)
+    public ResponseEntity<Object> handleProductNotFoundException(ProductNotFoundException exception) {
+        return new ResponseEntity<>(exception.getMessage(), HttpStatus.NOT_FOUND);
+    }
+
+    @ExceptionHandler(HttpServerErrorException.ServiceUnavailable.class)
+    public ResponseEntity<Object> handleException(HttpServerErrorException.ServiceUnavailable exception) {
+        return new ResponseEntity<>(exception.getMessage(), HttpStatus.INTERNAL_SERVER_ERROR);
+    }
+}

spring-cloud-modules/spring-cloud-open-telemetry/spring-cloud-open-telemetry1/src/main/java/com/baeldung/opentelemetry/exception/ProductNotFoundException.java

@@ -0,0 +1,7 @@
+package com.baeldung.opentelemetry.exception;
+
+public class ProductNotFoundException extends RuntimeException {
+    public ProductNotFoundException(String productNotFound) {
+        super(productNotFound);
+    }
+}

spring-cloud-modules/spring-cloud-open-telemetry/spring-cloud-open-telemetry1/src/main/java/com/baeldung/opentelemetry/model/Price.java

@@ -0,0 +1,39 @@
+package com.baeldung.opentelemetry.model;
+
+import com.fasterxml.jackson.annotation.JsonProperty;
+
+public class Price {
+
+    @JsonProperty("productId")
+    private long productId;
+
+    @JsonProperty("price_amount")
+    private double priceAmount;
+
+    @JsonProperty("discount")
+    private double discount;
+
+    public long getProductId() {
+        return productId;
+    }
+
+    public void setProductId(long productId) {
+        this.productId = productId;
+    }
+
+    public double getPriceAmount() {
+        return priceAmount;
+    }
+
+    public void setPriceAmount(double priceAmount) {
+        this.priceAmount = priceAmount;
+    }
+
+    public double getDiscount() {
+        return discount;
+    }
+
+    public void setDiscount(double discount) {
+        this.discount = discount;
+    }
+}

spring-cloud-modules/spring-cloud-open-telemetry/spring-cloud-open-telemetry1/src/main/java/com/baeldung/opentelemetry/model/Product.java

@@ -0,0 +1,27 @@
+package com.baeldung.opentelemetry.model;
+
+import com.fasterxml.jackson.annotation.JsonProperty;
+
+public class Product {
+
+    @JsonProperty("id")
+    private long id;
+
+    @JsonProperty("name")
+    private String name;
+
+    @JsonProperty("price")
+    private Price price;
+
+    public void setId(long id) {
+        this.id = id;
+    }
+
+    public void setName(String name) {
+        this.name = name;
+    }
+
+    public void setPrice(Price price) {
+        this.price = price;
+    }
+}

spring-cloud-modules/spring-cloud-open-telemetry/spring-cloud-open-telemetry1/src/main/java/com/baeldung/opentelemetry/repository/ProductRepository.java

@@ -0,0 +1,55 @@
+package com.baeldung.opentelemetry.repository;
+
+import com.baeldung.opentelemetry.exception.ProductNotFoundException;
+import com.baeldung.opentelemetry.model.Product;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.stereotype.Component;
+
+import javax.annotation.PostConstruct;
+import java.util.HashMap;
+import java.util.Map;
+
+@Component
+public class ProductRepository {
+
+    private static final Logger LOGGER = LoggerFactory.getLogger(ProductRepository.class);
+
+    private final Map<Long, Product> productMap = new HashMap<>();
+
+    public Product getProduct(Long productId){
+        LOGGER.info("Getting Product from Product Repo With Product Id {}", productId);
+
+        if(!productMap.containsKey(productId)){
+            LOGGER.error("Product Not Found for Product Id {}", productId);
+            throw new ProductNotFoundException("Product Not Found");
+        }
+
+        return productMap.get(productId);
+    }
+
+    @PostConstruct
+    private void setupRepo() {
+        Product product1 = getProduct(100001, "apple");
+        productMap.put(100001L, product1);
+
+        Product product2 = getProduct(100002, "pears");
+        productMap.put(100002L, product2);
+
+        Product product3 = getProduct(100003, "banana");
+        productMap.put(100003L, product3);
+
+        Product product4 = getProduct(100004, "mango");
+        productMap.put(100004L, product4);
+
+        Product product5 = getProduct(100005, "test");
+        productMap.put(100005L, product5);
+    }
+
+    private static Product getProduct(int id, String name) {
+        Product product = new Product();
+        product.setId(id);
+        product.setName(name);
+        return product;
+    }
+}

spring-cloud-modules/spring-cloud-open-telemetry/spring-cloud-open-telemetry1/src/main/resources/application.properties

@@ -0,0 +1,5 @@
+server.port= 8080
+spring.application.name=product-service
+priceClient.baseUrl=http://price-service:8081
+spring.sleuth.otel.config.trace-id-ratio-based=1.0
+spring.sleuth.otel.exporter.otlp.endpoint=http://collector:4317

spring-cloud-modules/spring-cloud-open-telemetry/spring-cloud-open-telemetry1/src/test/java/com/baeldung/opentelemetry/SpringContextTest.java

@@ -0,0 +1,16 @@
+package com.baeldung.opentelemetry;
+
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.test.context.junit.jupiter.SpringExtension;
+
+
+@ExtendWith(SpringExtension.class)
+@SpringBootTest(classes = ProductApplication.class)
+class SpringContextTest {
+    
+    @Test
+    void whenSpringContextIsBootstrapped_thenNoExceptions() {
+    }
+}

spring-cloud-modules/spring-cloud-open-telemetry/spring-cloud-open-telemetry1/src/test/java/com/baeldung/opentelemetry/controller/ProductControllerUnitTest.java

@@ -0,0 +1,92 @@
+package com.baeldung.opentelemetry.controller;
+
+import com.baeldung.opentelemetry.api.client.PriceClient;
+import com.baeldung.opentelemetry.exception.ProductNotFoundException;
+import com.baeldung.opentelemetry.model.Price;
+import com.baeldung.opentelemetry.model.Product;
+import com.baeldung.opentelemetry.repository.ProductRepository;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.autoconfigure.web.servlet.WebMvcTest;
+
+import org.springframework.boot.test.mock.mockito.MockBean;
+import org.springframework.http.HttpStatus;
+import org.springframework.test.context.junit.jupiter.SpringExtension;
+import org.springframework.test.web.servlet.MockMvc;
+import org.springframework.web.client.HttpServerErrorException;
+
+
+import static org.mockito.Mockito.when;
+import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.get;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;
+
+
+@ExtendWith(SpringExtension.class)
+@WebMvcTest(ProductController.class)
+class ProductControllerUnitTest {
+
+    @MockBean
+    private PriceClient priceCLient;
+
+    @MockBean
+    private ProductRepository productRepository;
+
+    @Autowired
+    private MockMvc mockMvc;
+
+
+    @Test
+    void givenProductandPriceDataAvailable_whenGetProductCalled_thenReturnProductDetails() throws Exception {
+        long productId = 100000L;
+
+        Price price = createPrice(productId);
+        Product product = createProduct(productId);
+        product.setPrice(price);
+
+        when(productRepository.getProduct(productId)).thenReturn(product);
+        when(priceCLient.getPrice(productId)).thenReturn(price);
+
+        mockMvc.perform(get("/product/" + productId))
+            .andExpect(status().is(HttpStatus.OK.value()));
+    }
+
+    @Test
+    void givenProductNotFound_whenGetProductCalled_thenReturnInternalServerError() throws Exception {
+        long productId = 100000L;
+        Price price = createPrice(productId);
+
+        when(productRepository.getProduct(productId)).thenThrow(ProductNotFoundException.class);
+        when(priceCLient.getPrice(productId)).thenReturn(price);
+
+        mockMvc.perform(get("/product/" + productId))
+            .andExpect(status().is(HttpStatus.NOT_FOUND.value()));
+    }
+
+    @Test
+    void givenPriceServiceNotAvailable_whenGetProductCalled_thenReturnInternalServerError() throws Exception {
+        long productId = 100000L;
+        Product product = createProduct(productId);
+
+        when(productRepository.getProduct(productId)).thenReturn(product);
+        when(priceCLient.getPrice(productId)).thenThrow(HttpServerErrorException.ServiceUnavailable.class);
+
+        mockMvc.perform(get("/product/" + productId))
+                .andExpect(status().is(HttpStatus.INTERNAL_SERVER_ERROR.value()));
+    }
+
+    private static Product createProduct(long productId) {
+        Product product = new Product();
+        product.setId(productId);
+        product.setName("test");
+        return product;
+    }
+
+    private static Price createPrice(long productId) {
+        Price price = new Price();
+        price.setProductId(productId);
+        price.setPriceAmount(12.00);
+        price.setDiscount(2.5);
+        return price;
+    }
+}

spring-cloud-modules/spring-cloud-open-telemetry/spring-cloud-open-telemetry2/Dockerfile

@@ -0,0 +1,7 @@
+FROM adoptopenjdk/openjdk11:alpine
+
+COPY target/spring-cloud-open-telemetry2-1.0.0-SNAPSHOT.jar spring-cloud-open-telemetry.jar
+
+EXPOSE 8081
+
+ENTRYPOINT ["java","-jar","/spring-cloud-open-telemetry.jar"]

spring-cloud-modules/spring-cloud-open-telemetry/spring-cloud-open-telemetry2/pom.xml

@@ -0,0 +1,115 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+    <artifactId>spring-cloud-open-telemetry2</artifactId>
+    <groupId>com.baeldung.spring.cloud</groupId>
+    <version>1.0.0-SNAPSHOT</version>
+    <name>spring-cloud-open-telemetry2</name>
+    <packaging>jar</packaging>
+
+    <parent>
+        <groupId>com.baeldung.spring.cloud</groupId>
+        <artifactId>spring-cloud-open-telemetry</artifactId>
+        <version>1.0.0-SNAPSHOT</version>
+    </parent>
+
+    <dependencyManagement>
+        <dependencies>
+            <dependency>
+                <groupId>org.springframework.boot</groupId>
+                <artifactId>spring-boot-dependencies</artifactId>
+                <version>${spring-boot-dependencies.version}</version>
+                <type>pom</type>
+                <scope>import</scope>
+            </dependency>
+            <dependency>
+                <groupId>org.springframework.cloud</groupId>
+                <artifactId>spring-cloud-dependencies</artifactId>
+                <version>${release.train.version}</version>
+                <type>pom</type>
+                <scope>import</scope>
+            </dependency>
+            <dependency>
+                <groupId>org.springframework.cloud</groupId>
+                <artifactId>spring-cloud-sleuth-otel-dependencies</artifactId>
+                <version>${spring-cloud-sleuth-otel.version}</version>
+                <scope>import</scope>
+                <type>pom</type>
+            </dependency>
+        </dependencies>
+    </dependencyManagement>
+
+    <dependencies>
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-starter-web</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>org.springframework.cloud</groupId>
+            <artifactId>spring-cloud-starter-sleuth</artifactId>
+            <exclusions>
+                <exclusion>
+                    <groupId>org.springframework.cloud</groupId>
+                    <artifactId>spring-cloud-sleuth-brave</artifactId>
+                </exclusion>
+            </exclusions>
+        </dependency>
+        <dependency>
+            <groupId>org.springframework.cloud</groupId>
+            <artifactId>spring-cloud-sleuth-otel-autoconfigure</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>io.opentelemetry</groupId>
+            <artifactId>opentelemetry-exporter-otlp-trace</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>io.grpc</groupId>
+            <artifactId>grpc-okhttp</artifactId>
+            <version>${grpc-okhttp.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>org.junit.jupiter</groupId>
+            <artifactId>junit-jupiter-engine</artifactId>
+            <version>${junit-jupiter.version}</version>
+            <scope>test</scope>
+        </dependency>
+    </dependencies>
+
+    <build>
+        <plugins>
+            <plugin>
+                <groupId>org.springframework.boot</groupId>
+                <artifactId>spring-boot-maven-plugin</artifactId>
+                <executions>
+                    <execution>
+                        <goals>
+                            <goal>repackage</goal>
+                        </goals>
+                    </execution>
+                </executions>
+            </plugin>
+        </plugins>
+    </build>
+
+    <repositories>
+        <repository>
+            <id>spring-milestones</id>
+            <url>https://repo.spring.io/milestone</url>
+        </repository>
+    </repositories>
+    <pluginRepositories>
+        <pluginRepository>
+            <id>spring-milestones</id>
+            <url>https://repo.spring.io/milestone</url>
+        </pluginRepository>
+    </pluginRepositories>
+
+    <properties>
+        <spring-boot-dependencies.version>2.5.7</spring-boot-dependencies.version>
+        <release.train.version>2020.0.4</release.train.version>
+        <spring-cloud-sleuth-otel.version>1.0.0-M12</spring-cloud-sleuth-otel.version>
+        <grpc-okhttp.version>1.42.1</grpc-okhttp.version>
+    </properties>
+
+</project>

spring-cloud-modules/spring-cloud-open-telemetry/spring-cloud-open-telemetry2/src/main/java/com/baeldung/opentelemetry/PriceApplication.java

@@ -0,0 +1,12 @@
+package com.baeldung.opentelemetry;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+
+@SpringBootApplication
+public class PriceApplication {
+
+    public static void main(String[] args) {
+        SpringApplication.run(PriceApplication.class, args);
+    }
+}

spring-cloud-modules/spring-cloud-open-telemetry/spring-cloud-open-telemetry2/src/main/java/com/baeldung/opentelemetry/controller/PriceController.java

@@ -0,0 +1,29 @@
+package com.baeldung.opentelemetry.controller;
+
+import com.baeldung.opentelemetry.model.Price;
+import com.baeldung.opentelemetry.repository.PriceRepository;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.PathVariable;
+import org.springframework.web.bind.annotation.RestController;
+
+@RestController
+public class PriceController {
+
+    private static final Logger LOGGER = LoggerFactory.getLogger(PriceController.class);
+
+    private final PriceRepository priceRepository;
+
+    @Autowired
+    public PriceController(PriceRepository priceRepository) {
+        this.priceRepository = priceRepository;
+    }
+
+    @GetMapping(path = "/price/{id}")
+    public Price getPrice(@PathVariable("id") long productId) {
+        LOGGER.info("Getting Price details for Product Id {}", productId);
+        return priceRepository.getPrice(productId);
+  }
+}

spring-cloud-modules/spring-cloud-open-telemetry/spring-cloud-open-telemetry2/src/main/java/com/baeldung/opentelemetry/exception/PriceNotFoundException.java

@@ -0,0 +1,7 @@
+package com.baeldung.opentelemetry.exception;
+
+public class PriceNotFoundException extends RuntimeException {
+    public PriceNotFoundException(String priceNotFound) {
+        super(priceNotFound);
+    }
+}

spring-cloud-modules/spring-cloud-open-telemetry/spring-cloud-open-telemetry2/src/main/java/com/baeldung/opentelemetry/exception/ProductControllerAdvice.java

@@ -0,0 +1,16 @@
+package com.baeldung.opentelemetry.exception;
+
+import org.springframework.http.HttpStatus;
+import org.springframework.http.ResponseEntity;
+import org.springframework.web.bind.annotation.ExceptionHandler;
+import org.springframework.web.bind.annotation.RestControllerAdvice;
+
+@RestControllerAdvice
+public class ProductControllerAdvice {
+
+    @ExceptionHandler(PriceNotFoundException.class)
+    public ResponseEntity<Object> handlePriceNotFoundException(PriceNotFoundException exception) {
+        return new ResponseEntity<>(exception.getMessage(), HttpStatus.NOT_FOUND);
+    }
+
+}

spring-cloud-modules/spring-cloud-open-telemetry/spring-cloud-open-telemetry2/src/main/java/com/baeldung/opentelemetry/model/Price.java

@@ -0,0 +1,27 @@
+package com.baeldung.opentelemetry.model;
+
+import com.fasterxml.jackson.annotation.JsonProperty;
+
+public class Price {
+
+    @JsonProperty("productId")
+    private long productId;
+
+    @JsonProperty("price_amount")
+    private double priceAmount;
+
+    @JsonProperty("discount")
+    private double discount;
+
+    public void setDiscount(double discount) {
+        this.discount = discount;
+	}
+
+    public void setProductId(long productId) {
+        this.productId = productId;
+    }
+
+    public void setPriceAmount(double priceAmount) {
+        this.priceAmount = priceAmount;
+    }
+}

spring-cloud-modules/spring-cloud-open-telemetry/spring-cloud-open-telemetry2/src/main/java/com/baeldung/opentelemetry/repository/PriceRepository.java

@@ -0,0 +1,53 @@
+package com.baeldung.opentelemetry.repository;
+
+import com.baeldung.opentelemetry.model.Price;
+import com.baeldung.opentelemetry.exception.PriceNotFoundException;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.stereotype.Component;
+
+import javax.annotation.PostConstruct;
+import java.util.HashMap;
+import java.util.Map;
+
+@Component
+public class PriceRepository {
+
+    private static final Logger LOGGER = LoggerFactory.getLogger(PriceRepository.class);
+
+    private final Map<Long, Price> priceMap = new HashMap<>();
+
+    public Price getPrice(Long productId){
+        LOGGER.info("Getting Price from Price Repo With Product Id {}", productId);
+
+        if(!priceMap.containsKey(productId)){
+            LOGGER.error("Price Not Found for Product Id {}", productId);
+            throw new PriceNotFoundException("Product Not Found");
+        }
+
+        return priceMap.get(productId);
+    }
+
+    @PostConstruct
+    private void setupRepo(){
+        Price price1 = getPrice(100001L, 12.5, 2.5);
+        priceMap.put(100001L, price1);
+
+        Price price2 = getPrice(100002L, 10.5, 2.1);
+        priceMap.put(100002L, price2);
+
+        Price price3 = getPrice(100003L, 18.5, 2.0);
+        priceMap.put(100003L, price3);
+
+        Price price4 = getPrice(100004L, 18.5, 2.0);
+        priceMap.put(100004L, price4);
+    }
+
+    private static Price getPrice(long productId, double priceAmount, double discount) {
+        Price price = new Price();
+        price.setProductId(productId);
+        price.setPriceAmount(priceAmount);
+        price.setDiscount(discount);
+        return price;
+    }
+}

spring-cloud-modules/spring-cloud-open-telemetry/spring-cloud-open-telemetry2/src/main/resources/application.properties

@@ -0,0 +1,4 @@
+server.port= 8081
+spring.application.name=price-service
+spring.sleuth.otel.config.trace-id-ratio-based=1.0
+spring.sleuth.otel.exporter.otlp.endpoint=http://collector:4317

spring-cloud-modules/spring-cloud-open-telemetry/spring-cloud-open-telemetry2/src/test/java/com/baeldung/opentelemetry/SpringContextTest.java

@@ -0,0 +1,16 @@
+package com.baeldung.opentelemetry;
+
+import org.junit.jupiter.api.Test;
+
+import org.junit.jupiter.api.extension.ExtendWith;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.test.context.junit.jupiter.SpringExtension;
+
+@ExtendWith(SpringExtension.class)
+@SpringBootTest(classes = PriceApplication.class)
+class SpringContextTest {
+    
+    @Test
+    void whenSpringContextIsBootstrapped_thenNoException() {
+    }
+}

spring-cloud-modules/spring-cloud-open-telemetry/spring-cloud-open-telemetry2/src/test/java/com/baeldung/opentelemetry/controller/PriceControllerUnitTest.java

@@ -0,0 +1,57 @@
+package com.baeldung.opentelemetry.controller;
+
+
+import com.baeldung.opentelemetry.exception.PriceNotFoundException;
+import com.baeldung.opentelemetry.model.Price;
+import com.baeldung.opentelemetry.repository.PriceRepository;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.autoconfigure.web.servlet.WebMvcTest;
+import org.springframework.boot.test.mock.mockito.MockBean;
+import org.springframework.http.HttpStatus;
+import org.springframework.test.context.junit.jupiter.SpringExtension;
+import org.springframework.test.web.servlet.MockMvc;
+
+import static org.mockito.Mockito.when;
+import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.get;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;
+
+
+@ExtendWith(SpringExtension.class)
+@WebMvcTest(PriceController.class)
+class PriceControllerUnitTest {
+
+    @MockBean
+    private PriceRepository priceRepository;
+
+    @Autowired
+    private MockMvc mockMvc;
+
+    @Test
+    void givenProductandPriceAvailable_whenGetProductCalled_thenReturnProductDetails() throws Exception {
+        long productId = 100000L;
+        Price price = new Price();
+        price.setProductId(productId);
+        price.setPriceAmount(12.00);
+        price.setDiscount(2.5);
+
+        when(priceRepository.getPrice(productId)).thenReturn(price);
+
+        mockMvc.perform(get("/price/" + productId))
+          .andExpect(status().is(HttpStatus.OK.value()));
+    }
+
+
+    @Test
+    void givenProductNotFound_whenGetProductCalled_thenReturnInternalServerError() throws Exception {
+        long productId = 100000L;
+
+        when(priceRepository.getPrice(productId)).thenThrow(PriceNotFoundException.class);
+
+        mockMvc.perform(get("/price/" + productId))
+          .andExpect(status().is(HttpStatus.NOT_FOUND.value()));
+    }
+
+}