第13章 Prometheus metrics monitoring in Red Hat Decision Manager

Procedure

1. In your KIE Server instance, set the org.kie.prometheus.server.ext.disabled system property to false to enable the Prometheus extension. You can define this property when you start KIE Server or in the standalone.xml or standalone-full.xml file of Red Hat Decision Manager distribution.

2. If you are running Red Hat Decision Manager on Spring Boot, configure the required key in the application.properties system property:

   Spring Boot application.properties key for Red Hat Decision Manager and Prometheus

   kieserver.drools.enabled=true
   kieserver.dmn.enabled=true
   kieserver.prometheus.enabled=true

3. In the prometheus.yaml file of your Prometheus distribution, add the following settings in the scrape_configs section to configure Prometheus to scrape metrics from KIE Server:

   Scrape configurations in prometheus.yaml file

   scrape_configs:
     - job_name: 'kie-server'
       metrics_path: /SERVER_PATH/services/rest/metrics
       basicAuth:
         username: USER_NAME
         password: PASSWORD
       static_configs:
         - targets: ["HOST:PORT"]

   Scrape configurations in prometheus.yaml file for Spring Boot (if applicable)

   scrape_configs:
     - job_name: 'kie'
       metrics_path: /rest/metrics
       static_configs:
         - targets: ["HOST:PORT"]

   Replace the values according to your KIE Server location and settings.

4. Start the KIE Server instance.

   Example start command for Red Hat Decision Manager on Red Hat JBoss EAP

   $ cd ~/EAP_HOME/bin
   $ ./standalone.sh --c standalone-full.xml

   After you start the configured KIE Server instance, Prometheus begins collecting metrics and KIE Server publishes the metrics to the REST API endpoint http://HOST:PORT/SERVER/services/rest/metrics (or on Spring Boot, to http://HOST:PORT/rest/metrics).

5. In a REST client or curl utility, send a REST API request with the following components to verify that KIE Server is publishing the metrics:

   For REST client:

   • Authentication: Enter the user name and password of the KIE Server user with the kie-server role.

   • HTTP Headers: Set the following header:

     • Accept: application/json
   • HTTP method: Set to GET.
   • URL: Enter the KIE Server REST API base URL and metrics endpoint, such as http://localhost:8080/kie-server/services/rest/metrics (or on Spring Boot, http://localhost:8080/rest/metrics).

   For curl utility:

   • -u: Enter the user name and password of the KIE Server user with the kie-server role.

   • -H: Set the following header:

     • accept: application/json
   • -X: Set to GET.
   • URL: Enter the KIE Server REST API base URL and metrics endpoint, such as http://localhost:8080/kie-server/services/rest/metrics (or on Spring Boot, http://localhost:8080/rest/metrics).

   Example curl command for Red Hat Decision Manager on Red Hat JBoss EAP

   curl -u 'baAdmin:password@1' -X GET "http://localhost:8080/kie-server/services/rest/metrics"

   Example curl command for Red Hat Decision Manager on Spring Boot

   curl -u 'baAdmin:password@1' -X GET "http://localhost:8080/rest/metrics"

   Example server response

   # HELP kie_server_container_started_total Kie Server Started Containers
   # TYPE kie_server_container_started_total counter
   kie_server_container_started_total{container_id="task-assignment-kjar-1.0",} 1.0
   # HELP solvers_running Number of solvers currently running
   # TYPE solvers_running gauge
   solvers_running 0.0
   # HELP dmn_evaluate_decision_nanosecond DMN Evaluation Time
   # TYPE dmn_evaluate_decision_nanosecond histogram
   # HELP solver_duration_seconds Time in seconds it took solver to solve the constraint problem
   # TYPE solver_duration_seconds summary
   solver_duration_seconds_count{solver_id="100tasks-5employees.xml",} 1.0
   solver_duration_seconds_sum{solver_id="100tasks-5employees.xml",} 179.828255925
   solver_duration_seconds_count{solver_id="24tasks-8employees.xml",} 1.0
   solver_duration_seconds_sum{solver_id="24tasks-8employees.xml",} 179.995759653
   # HELP drl_match_fired_nanosecond Drools Firing Time
   # TYPE drl_match_fired_nanosecond histogram
   # HELP dmn_evaluate_failed_count DMN Evaluation Failed
   # TYPE dmn_evaluate_failed_count counter
   # HELP kie_server_start_time Kie Server Start Time
   # TYPE kie_server_start_time gauge
   kie_server_start_time{name="myapp-kieserver",server_id="myapp-kieserver",location="http://myapp-kieserver-demo-monitoring.127.0.0.1.nip.io:80/services/rest/server",version="7.4.0.redhat-20190428",} 1.557221271502E12
   # HELP kie_server_container_running_total Kie Server Running Containers
   # TYPE kie_server_container_running_total gauge
   kie_server_container_running_total{container_id="task-assignment-kjar-1.0",} 1.0
   # HELP solver_score_calculation_speed Number of moves per second for a particular solver solving the constraint problem
   # TYPE solver_score_calculation_speed summary
   solver_score_calculation_speed_count{solver_id="100tasks-5employees.xml",} 1.0
   solver_score_calculation_speed_sum{solver_id="100tasks-5employees.xml",} 6997.0
   solver_score_calculation_speed_count{solver_id="24tasks-8employees.xml",} 1.0
   solver_score_calculation_speed_sum{solver_id="24tasks-8employees.xml",} 19772.0

   If the metrics are not available in KIE Server, review and verify the KIE Server and Prometheus configurations described in this section.

   You can also interact with your collected metrics in the Prometheus expression browser at http://HOST:PORT/graph, or integrate your Prometheus data source with a data-graphing tool such as Grafana:

   図13.1 Prometheus expression browser with KIE Server metrics

   

   図13.2 Prometheus expression browser with KIE Server target

   

   図13.3 Grafana dashboard with KIE Server metrics for DMN models

   

   図13.4 Grafana dashboard with KIE Server metrics for solvers