Introduction#

Elastic APM instruments the applications to ship performance metrics to Elasticsearch for visualization in Kibana with pre-configured dashboards. This article demonstrates, how we can use Elastic Apm with spring boot application for monitoring.

In business, the idea of measuring what you are doing, picking the measurements that count like customer satisfaction and performance… you thrive on that. - Bill Gates

Example Scenario#

First of all, We need to create one spring boot project with JPA support, to do so I will use a spring command line which will create a skeleton project for us.

The following command we need to run for the setup of the project:

spring init\
 -n=order-service\
 -d=web,jpa,h2,lombok\
 --groupId=io.github.bhuwanupadhyay\
 --package-name=io.github.bhuwanupadhyay.order\
 --description="Order Service"\
 --version=1.0-SNAPSHOT\
 --language=java \
order-service

Note: if you don’t have spring command line tool yet please refer. Now, Let’s create simple CRUD operation REST endpoints for order domain.

@Entity
@Table(name = "app_orders")
@Getter
class Order {
    @Id
    private String orderId;
    private String itemId;
    private String customerId;
}

interface OrderRepository extends CrudRepository<Order, String> {
}

@RestController
@RequestMapping("/orders")
@RequiredArgsConstructor
class OrderEndpoints {
    private final OrderRepository repository;

    @GetMapping
    public ResponseEntity<List<Order>> listOrders() {
        return ResponseEntity.ok((List<Order>) repository.findAll());
    }

    @PostMapping
    public ResponseEntity<Order> createOrder(@RequestBody Order order) {
        return ResponseEntity.ok(repository.save(order));
    }
}

The Dockerfile for order-service application to run elastic-apm-agent.jar

FROM openjdk:8-jdk-alpine
VOLUME /tmp
ARG JAR_FILE
ARG ELASTIC_APM_AGEN_VERSION=0.7.0
RUN wget https://search.maven.org/remotecontent?filepath=co/elastic/apm/elastic-apm-agent/${ELASTIC_APM_AGEN_VERSION}/elastic-apm-agent-${ELASTIC_APM_AGEN_VERSION}.jar \
    -O ${HOME}/elastic-apm-agent.jar
COPY ${JAR_FILE} app.jar
ENTRYPOINT [
    "java",
    "-javaagent:${HOME}/elastic-apm-agent.jar",
    "-Djava.security.egd=file:/dev/./urandom",
    "-jar",
    "/app.jar"
    ]

The complete docker-compose.yml file which includes all necessary components:

• Elasticsearch
• Kibana
• Elastic APM Server
• Order Service [ Spring Boot Application ]

version: '3'
services:
  apm-elasticsearch:
    ports:
      - "9200:9200"
  kibana:
    environment:
      ELASTICSEARCH_URL: http://apm-elasticsearch:9200
    ports:
      - "5601:5601"
    links:
      - apm-elasticsearch
    depends_on:
      - apm-elasticsearch
  elastic-apm-server:
    command: [
      'bash',
      '-c',
      "apm-server run -e -E output.elasticsearch.hosts=['http://apm-elasticsearch:9200']",
    ]
    ports:
      - "8200:8200"
    links:
      - apm-elasticsearch
    depends_on:
      - apm-elasticsearch
  order-service:
    build:
      context: ../archive
      dockerfile: Dockerfile
      args:
        - JAR_FILE=target/order-service-1.0-SNAPSHOT.jar
    ports:
      - "8080:8080"
    environment:
      ELASTIC_APM_SERVICE_NAME: order-service
      ELASTIC_APM_APPLICATION_PACKAGES: io.github.bhuwanupadhyay
      ELASTIC_APM_SERVER_URLS: http://elastic-apm-server:8200
    links:
      - elastic-apm-server
    depends_on:
      - elastic-apm-server

The following command to launch service with elastic apm agent and apm server components:

mvn clean package && docker-compose up

Finally, we need to perform load testing to see some result in kibana dashboard. To do so i will use load testing tool artillery.

mkdir artillery-load-testing
cd artillery-load-testing
touch package.json script.yml processor.js

package.json

{
  "name": "artillery-load-testing",
  "version": "1.0.0",
  "description": "Artillery Load Testing",
  "main": "index.js",
  "scripts": {
    "test": "./node_modules/.bin/artillery run script.yml"
  },
  "license": "MIT",
  "dependencies": {
    "artillery": "^1.6.0-24",
    "uuid": "^3.3.2"
  }
}

script.yml

config:
  target: 'http://localhost:8080'
  processor: './processor.js'
  phases:
    - duration: 60
      arrivalRate: 20
scenarios:
  - name: 'POST'
    flow:
      - post:
          headers:
            content-type: 'application/json'
          url: '/orders'
          beforeRequest: 'assignNewId'
          body: |
            {
              "orderId": "@@id@@",
              "itemId": "1",
              "customerId": "1"
            }

processor.js

'use strict';

const uuidv1 = require('uuid/v1');
// noinspection JSUnresolvedVariable
module.exports = { assignNewId };

function assignNewId(requestParams, context, eventEmitter, done) {
  const id = uuidv1();
  requestParams.body = requestParams.body.replace('@@id@@', id);
  return done();
}

The following command to perform load testing:

npm install
npm run test

Now, we need to analyze performance metrics in kibana dashboard under APM menu link in the left sidebar.