Add observation support

Add banner
Fix docker volume location
Improve swagger documentation
Remove unused ID in Product request

.gitignore

@@ -31,3 +31,6 @@ build/
 
 ### VS Code ###
 .vscode/
+
+### Docker volumes ###
+/docker/volumes/

docker-compose.yml

@@ -9,4 +9,4 @@ services:
       MONGO_INITDB_ROOT_PASSWORD: password
       MONGO_INITDB_DATABASE: product-service
     volumes:
-      - ./docker/mongodb/data:/data/db
+      - ./docker/volumes/mongodb/data:/data/db

pom.xml

@@ -55,6 +55,45 @@
 			<artifactId>lombok</artifactId>
 			<optional>true</optional>
 		</dependency>
+		<!-- Observation -->
+		<!-- Enable AOP for the endpoints -->
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-aop</artifactId>
+		</dependency>
+		<!-- Enable JVM Metrics -->
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-actuator</artifactId>
+		</dependency>
+		<!-- Configure Micrometer to expose an endpoint that can be scraped by Prometheus. -->
+		<dependency>
+			<groupId>io.micrometer</groupId>
+			<artifactId>micrometer-registry-prometheus</artifactId>
+			<scope>runtime</scope>
+		</dependency>
+		<!-- Add distributed tracing capabilities to our application -->
+		<dependency>
+			<groupId>io.micrometer</groupId>
+			<artifactId>micrometer-tracing-bridge-brave</artifactId>
+		</dependency>
+		<dependency>
+			<groupId>io.zipkin.reporter2</groupId>
+			<artifactId>zipkin-reporter-brave</artifactId>
+		</dependency>
+		<!-- Add datasource monitoring -->
+		<dependency>
+			<groupId>net.ttddyy.observation</groupId>
+			<artifactId>datasource-micrometer-spring-boot</artifactId>
+			<version>1.0.1</version>
+		</dependency>
+		<!-- Logging -->
+		<dependency>
+			<groupId>com.github.loki4j</groupId>
+			<artifactId>loki-logback-appender</artifactId>
+			<version>1.3.2</version>
+		</dependency>
+		<!-- Test dependencies -->
 		<dependency>
 			<groupId>org.springframework.boot</groupId>
 			<artifactId>spring-boot-starter-test</artifactId>

src/main/java/com/example/microservices/product/config/ObservationConfig.java

@@ -0,0 +1,14 @@
+package com.example.microservices.product.config;
+
+import io.micrometer.observation.ObservationRegistry;
+import io.micrometer.observation.aop.ObservedAspect;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+
+@Configuration
+public class ObservationConfig {
+    @Bean
+    ObservedAspect observedAspect(ObservationRegistry registry) {
+        return new ObservedAspect(registry);
+    }
+}

src/main/java/com/example/microservices/product/controller/ProductController.java

@@ -12,7 +12,6 @@
 import com.example.microservices.product.service.ProductService;
 
 import io.swagger.v3.oas.annotations.Operation;
-import io.swagger.v3.oas.annotations.Parameters;
 import io.swagger.v3.oas.annotations.media.ArraySchema;
 import io.swagger.v3.oas.annotations.media.Content;
 import io.swagger.v3.oas.annotations.media.Schema;

src/main/java/com/example/microservices/product/dto/ProductRequest.java

@@ -1,7 +1,9 @@
 package com.example.microservices.product.dto;
 
 import java.math.BigDecimal;
+import io.swagger.v3.oas.annotations.media.Schema;
 
-public record ProductRequest(String id, String name, String description,
-                String skuCode, BigDecimal price) {
+@Schema(description = "Details the product to create")
+public record ProductRequest(String name, String description,
+        String skuCode, BigDecimal price) {
 }

src/main/java/com/example/microservices/product/dto/ProductResponse.java

@@ -2,6 +2,9 @@
 
 import java.math.BigDecimal;
 
+import io.swagger.v3.oas.annotations.media.Schema;
+
+@Schema(description = "Product details")
 public record ProductResponse(String id, String name, String description,
         String skuCode, BigDecimal price) {
 }

src/main/java/com/example/microservices/product/repository/ProductRepository.java

@@ -4,5 +4,8 @@
 
 import com.example.microservices.product.model.Product;
 
+import io.micrometer.observation.annotation.Observed;
+
+@Observed
 public interface ProductRepository extends MongoRepository<Product, String> {
 }

src/main/resources/application.properties

@@ -1,4 +1,4 @@
-spring.application.name=product
+spring.application.name=product-service
 ## MongoDB
 spring.data.mongodb.uri=mongodb://root:password@localhost:27017/product-service?authSource=admin
 ## Swagger
@@ -8,3 +8,12 @@ springdoc.api-docs.enabled=true
 springdoc.api-docs.path=/api-docs
 springdoc.packagesToScan=com.example.microservices.product.controller
 springdoc.pathsToMatch=/**
+
+## Observation management
+management.endpoints.web.exposure.include=health, info, metrics, prometheus
+management.metrics.distribution.percentiles-histogram.http.server.requests=true
+management.observations.key-values.application=product-service
+management.tracing.sampling.probability=1.0
+
+# Loki URL
+loki.url=http://localhost:3100/loki/api/v1/push

src/main/resources/banner.txt

@@ -0,0 +1,9 @@
+______              _            _     _____                 _          
+| ___ \            | |          | |   /  ___|               (_)         
+| |_/ / __ ___   __| |_   _  ___| |_  \ `--.  ___ _ ____   ___  ___ ___ 
+|  __/ '__/ _ \ / _` | | | |/ __| __|  `--. \/ _ \ '__\ \ / / |/ __/ _ \
+| |  | | | (_) | (_| | |_| | (__| |_  /\__/ /  __/ |   \ V /| | (_|  __/
+\_|  |_|  \___/ \__,_|\__,_|\___|\__| \____/ \___|_|    \_/ |_|\___\___|
+
+${application.title} ${application.version}
+Powered by Spring Boot ${spring-boot.version}

src/main/resources/logback-spring.xml

@@ -0,0 +1,25 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<configuration>
+    <include resource="org/springframework/boot/logging/logback/base.xml"/>
+    <springProperty scope="context" name="appName" source="spring.application.name"/>
+    <springProperty scope="context" name="lokiUrl" source="loki.url"/>
+
+    <appender name="LOKI" class="com.github.loki4j.logback.Loki4jAppender">
+        <http>
+            <url>${lokiUrl}</url>
+        </http>
+        <format>
+            <label>
+                <pattern>application=${appName},host=${HOSTNAME},level=%level</pattern>
+            </label>
+            <message>
+                <pattern>${FILE_LOG_PATTERN}</pattern>
+            </message>
+            <sortByTime>true</sortByTime>
+        </format>
+    </appender>
+
+    <root level="INFO">
+        <appender-ref ref="LOKI"/>
+    </root>
+</configuration>

src/test/java/com/example/microservices/product/ProductApplicationTests.java

@@ -59,7 +59,7 @@ void shouldCreateProduct() throws Exception {
 	}
 
 	private ProductRequest getProductRequest() {
-		return new ProductRequest("iPhone 13", "iPhone 13", "iPhone 13", "iPhone 13", BigDecimal.valueOf(1200));
+		return new ProductRequest("iPhone 13", "iPhone 13", "iPhone 13", BigDecimal.valueOf(1200));
 	}
 
 	@Test