inoxx03 / spring-boot-jolokia

Instructions to start Spring Boot with jolokia agent

When a Spring Boot application is deployed on Openshift using the openjdk java 1.8 S2I docker image, the jolokia agent is deployed within the image and, when the docker container is starter, then it is instrumented by the java -javaagent parameter. The HTTPS service exposed by Jolokia allows to access using the HTTP protocol the information about the MBeans created within the JVM.

The Jolokia service can be customized using the following parameters defined within the DeploymentConfig resource as env variables :

• AB_JOLOKIA_USER = "jolokia"
• AB_JOLOKIA_PASSWORD = "admin123"
• AB_JOLOKIA_PASSWORD_RANDOM = "false"

Remark : The list of the paramters available is defined here

Run the project locally

mvn clean package
java -javaagent:jar/jolokia-jvm-1.3.7-agent.jar=config=etc/jolokia.properties -jar target/spring-boot-jolokia-1.0.0-SNAPSHOT.jar

Query the Jolokia Service

• Get the Jolokia Info

curl -v -u jolokia:admin123 http://localhost:8778/jolokia/

or

http --auth jolokia:admin123 http://localhost:8778/jolokia/version
...

{
    "request": {
        "type": "version"
    },
    "status": 200,
    "timestamp": 1510659657,
    "value": {
        "agent": "1.3.7",
        "config": {
            "agentContext": "/jolokia",
            "agentId": "192.168.1.80-52647-2503dbd3-jvm",
            "agentType": "jvm",
            "debug": "false",
            "debugMaxEntries": "100",
            "discoveryEnabled": "true",
            "historyMaxEntries": "10",
            "maxCollectionSize": "0",
            "maxDepth": "15",
            "maxObjects": "0"
        },
        "info": {
            "product": "tomcat",
            "vendor": "Apache",
            "version": "8.5.23"
        },
        "protocol": "7.2"
    }
}

• Get the Memory usage

http --auth jolokia:admin123 http://localhost:8778/jolokia/read/java.lang:type\=Memory/HeapMemoryUsage
HTTP/1.1 200 OK
...

{
    "request": {
        "attribute": "HeapMemoryUsage",
        "mbean": "java.lang:type=Memory",
        "type": "read"
    },
    "status": 200,
    "timestamp": 1510660614,
    "value": {
        "committed": 378535936,
        "init": 268435456,
        "max": 3817865216,
        "used": 132615736
    }
}

Deploy on OpenShift

oc new-project demo-jolokia
mvn clean package fabric8:deploy -Popenshift

Access Jolokia Https Service

• Get the jolokia route endpoint

JOLOKIA_URL=$(oc get route spring-boot-monitoring-jolokia -o jsonpath='https://{.spec.host}')

• Next issue a curl or httpie request

curl -k -u jolokia:admin123 $JOLOKIA_URL/jolokia/version

or

http --verify=no --auth jolokia:admin123 $JOLOKIA_URL/jolokia/version

Install manually the Jolokia service/route

• Create Service/Route on Openshift

oc delete route/spring-boot-http-jolokia
oc delete svc/spring-boot-http-jolokia
oc create -f src/fabric8/jolokia-svc.yaml          
oc create -f src/fabric8/jolokia-route.yaml