Prometheus configuration

Prometheus is a Open Source monitorization system which some interesting features for event monitoring and alerting. You can find a more detailed description at https://prometheus.io/.

This endpoint is already included in OpenKM since v8.1.10. To enable it you need to include these two lines at openkm.properties configuration file:

Once modified you need to restart OpenKM and the endpoint http://localhost:8080/openkm/actuator/prometheus will be available. This endpoint is protected and will be only accesible for users with the ROLE_ACTUATOR or ROLE_ADMIN roles.

Setup validation

In order to verify the access is valid, open a terminal and execute this command:

If the user and password matches, and the user has the right ROLE_ACTUATOR role the output will be something like:

Running Prometheus with Docker

The easiest way to get Prometheus running is using the Docker image, so we need to get it:

Once we have the image we need to create the prometheus.yml configuration file:

global:
  scrape_interval:     15s # Set the scrape interval to every 15 seconds. Default is every 1 minute.
  evaluation_interval: 15s # Evaluate rules every 15 seconds. The default is every 1 minute.
  # scrape_timeout is set to the global default (10s).

# Load rules once and periodically evaluate them according to the global 'evaluation_interval'.
rule_files:
  # - "first_rules.yml"
  # - "second_rules.yml"

# A scrape configuration containing exactly one endpoint to scrape:
# Here it's Prometheus itself.
scrape_configs:
  # The job name is added as a label `job=<job_name>` to any timeseries scraped from this config.
  - job_name: 'prometheus'
    # metrics_path defaults to '/metrics'
    # scheme defaults to 'http'.
    static_configs:
    - targets: ['127.0.0.1:9090']

  - job_name: 'spring-actuator'
    metrics_path: '/openkm/actuator/prometheus'
    scrape_interval: 5s
    static_configs:
    - targets: ['172.18.0.1:8080']
    basic_auth:
      username: 'okmAdmin'
      password: 'admin'

Let's create the appropiate Docker Compose file:

version: '3.2'

services:

  prometheus:
    image: prom/prometheus
    container_name: prometheus
    hostname: prometheus
    command:
      - "--config.file=/etc/prometheus/prometheus.yml"
    ports:
      - 9090:9090
    volumes:
      - ./prometheus.yml:/etc/prometheus/prometheus.yml

And you can start it by:

Once started, Prometheus will be accesible at http://localhost:9090/ and you can see a graph of application CPU usage filtering by "process_cpu_usage":

Grafana will be available at http://localhost:3000/ and to login use "admin" as default user and password. Go to "Data sources" and add a Prometheus datasource using the URL http://172.18.0.1:9090. To create a sample dashboard, go to Dashboard  and click on "Create Dashboard" button. After that click on "Import dashboard" and choose the "spring boot template" which has the id 11378. Use the previously created Prometheus datasource.

More info at Prometheus and Grafana websites.