Merge pull request #6 from spotguides/kafka

Add optional KafkaController

.banzaicloud/charts/spotguide-spring-boot/templates/deployment.yaml

@@ -57,6 +57,8 @@ spec:
                 secretKeyRef:
                   name: {{ if .Values.mysql.existingSecret }}{{ .Values.mysql.existingSecret }}{{- else }}{{ include "call-nested" (list . "mysql" "mysql.fullname") }}{{- end }}
                   key: mysql-password
+            - name: SPRING_KAFKA_BOOTSTRAP_SERVERS
+              value: {{ .Values.kafka.bootstrapServers }}
             {{ range $key, $value := .Values.env }}
             - name: {{ $key }}
               value: {{ $value | quote }}

.banzaicloud/charts/spotguide-spring-boot/values.yaml

@@ -55,6 +55,10 @@ mysql:
     livenessProbe:
       initialDelaySeconds: 200
 
+kafka:
+  enabled: false
+  bootstrapServers: "kafka-headless.kafka:29092"
+
 pipeline-ingress:
   enabled: false
 

.banzaicloud/pipeline.yaml

@@ -36,7 +36,7 @@ pipeline:
     image: lachlanevenson/k8s-helm:latest
     commands:
     - helm init -c
-    - helm repo add banzaicloud-stable http://kubernetes-charts.banzaicloud.com/branch/master
+    - helm repo add banzaicloud-stable https://kubernetes-charts.banzaicloud.com
     - helm dep update ./.banzaicloud/charts/spotguide-spring-boot
     - helm package ./.banzaicloud/charts/spotguide-spring-boot
 

README.md

@@ -135,7 +135,7 @@ Our [`Spring Boot Actuator` library](https://docs.spring.io/spring-boot/docs/cur
 
 ## Endpoints
 
-These are the implemented REST endpoints in the sample application.
+These are the available REST endpoints in the sample application:
 
 ### `GET /actuator/health/kubernetes`
 
@@ -149,7 +149,6 @@ Kubernetes endpoint, returns basic [Pod](https://kubernetes.io/docs/concepts/wor
 
 Health check, liveness probe endpoint. Returns `200` when the application is healthy, can reach the database.
 
-
 ### `GET /api/v1/users`
 
 Fetch all users.
@@ -179,6 +178,22 @@ Update a user. The request body has the same schema as [`POST /api/v1/users`](#p
 
 Delete a user.
 
+## Optional Kafka endpoints if running with SPRING_KAFKA_ENABLED=true
+
+### `GET /api/v1/kafka`
+
+Fetch all Kafka messages.
+
+### `POST /api/v1/kafka`
+
+Send a new message to the `"spring-boot"` Kafka topic.
+
+```json
+{
+  "message": "hello-spring-boot"
+}
+```
+
 ## Build Run and Test locally
 
 ```bash
@@ -205,5 +220,5 @@ mvn clean package -DskipTests
 
 SPRING_DATASOURCE_USERNAME=sparky SPRING_DATASOURCE_PASSWORD=sparky123 java -jar target/app.jar
 
-curl -H "Content-Type: application/json" http://localhost:8080/users -d '{"userName":"john","email":"[email protected]"}'
+curl -H "Content-Type: application/json" http://localhost:8080/api/v1/users -d '{"userName":"john","email":"[email protected]"}'
 ```

docker-compose.yml

@@ -12,3 +12,20 @@ services:
       MYSQL_PASSWORD: sparky123
     ports:
       - 3306:3306
+
+  zookeeper:
+    image: wurstmeister/zookeeper
+    ports:
+      - 2181:2181
+
+  kafka:
+    image: wurstmeister/kafka
+    depends_on:
+      - zookeeper
+    ports:
+      - 9092:9092
+    environment:
+      KAFKA_ADVERTISED_HOST_NAME: 127.0.0.1
+      KAFKA_ZOOKEEPER_CONNECT: zookeeper:2181
+    volumes:
+      - /var/run/docker.sock:/var/run/docker.sock

pom.xml

@@ -60,6 +60,11 @@
             <version>${spring-cloud-kubernetes.version}</version>
         </dependency>
 
+        <dependency>
+            <groupId>org.springframework.kafka</groupId>
+            <artifactId>spring-kafka</artifactId>
+        </dependency>
+
         <dependency>
             <groupId>org.springframework.boot</groupId>
             <artifactId>spring-boot-devtools</artifactId>
@@ -110,7 +115,7 @@
             <plugin>
                 <groupId>com.google.cloud.tools</groupId>
                 <artifactId>jib-maven-plugin</artifactId>
-                <version>1.0.2</version>
+                <version>1.7.0</version>
                 <configuration>
                     <from>
                         <image>gcr.io/distroless/java:11</image>

src/main/java/com/banzaicloud/spotguide/KafkaController.java

@@ -0,0 +1,46 @@
+package com.banzaicloud.spotguide;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.autoconfigure.condition.ConditionalOnProperty;
+import org.springframework.http.HttpStatus;
+import org.springframework.http.ResponseEntity;
+import org.springframework.kafka.annotation.KafkaListener;
+import org.springframework.kafka.core.KafkaTemplate;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.PostMapping;
+import org.springframework.web.bind.annotation.RequestBody;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RestController;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Map;
+
+@RestController
+@RequestMapping("/api/v1/kafka")
+@ConditionalOnProperty(value = "spring.kafka.enabled", havingValue = "true")
+public class KafkaController {
+
+    private static final String BOOT_TOPIC = "spring-boot";
+
+    private final List<String> messages = new ArrayList<>();
+
+    @Autowired
+    private KafkaTemplate<String, String> kafkaTemplate;
+
+    @PostMapping
+    public ResponseEntity sendMessage(@RequestBody Map<String, String> body) {
+        kafkaTemplate.send(BOOT_TOPIC, body.get("message"));
+        return new ResponseEntity(HttpStatus.ACCEPTED);
+    }
+
+    @GetMapping
+    public List<String> listMessages() {
+        return messages;
+    }
+
+    @KafkaListener(topics = KafkaController.BOOT_TOPIC)
+    public void consume(String message) {
+        messages.add(message);
+    }
+}

src/main/resources/application.yml

@@ -10,6 +10,12 @@ spring:
     username: sparky
     password: sparky123
 
+  kafka:
+    enabled: false
+    bootstrap-servers: localhost:9092
+    consumer:
+      group-id: myGroup
+
 # There is an issue with `spring-cloud-starter-config`, when mixed with `spring-boot-starter-data-jpa` and `Spring Boot v2.1.x`.
 # https://github.com/spring-cloud/spring-cloud-security/issues/143#issuecomment-376391930
 spring.main.allow-bean-definition-overriding: true