isabella232 / cloud-foundry-sampleapp

Wavefront Cloud Foundry (Spring Boot) Sample Application

Wavefront Cloud Foundry Sample Spring Boot Application

This project describes how to send application metrics from a Spring Boot app running in PCF to a Wavefront proxy.

Requirements

• A Wavefront proxy deployed in PCF as part of the Wavefront by VMware Nozzle for PCF
• A Wavefront proxy service instance provisioned in PCF using the Wavefront Service Broker for PCF.
• Java >= 1.8
• Maven

Wavefront Proxy

The rest of this document assumes the wavefront proxy service instance provisioned in PCF is called wfproxy-service. Replace the service name accordingly if different.

Application Manifest

A manifest.yml file is used to provide parameters to a PCF application. The developer needs to identify the wavefront proxy running in PCF and add it to the manifest file.

Here is a sample manifest file:

---
 services:
  - wfproxy-service

Maven pom.xml File

Update the Maven pom.xml file to include the wavefrontHQ public repositories and dependencies dropwizard-metrics-3.1. It should also include spring-boot-maven-plugin and maven-shade-plugin.

Parse VCAP_SERVICES

The VCAP_SERVICES present in the manifest file (or externally bound to the application using cf bind-services ... command) are passed to the application as environment variable. It is parsed to retrieve the wavefront-proxy hostname and port:

VCAP_SERVICES =
{
  "wavefront-proxy": [
    {
      "credentials": {
        "hostname": "10.202.1.15",
        "port": 2878
      },
      "syslog_drain_url": null,
      "volume_mounts": [],
      "label": "wavefront-proxy",
      "provider": null,
      "plan": "standard",
      "name": "wfproxy-service",
      "tags": [
        "wavefront",
        "metrics"
      ]
    }
  ]
}

Send metrics from the application

Most of the sample code is present in the MetricSystem.java file. It determines all the metrics to be reported and adds them to the metricRegistry. The WavefrontReporter is then used to send the metrics to the proxy.

WavefrontReporter wfReporter = WavefrontReporter.forRegistry(metricRegistry)
    .withSource("springboot")
    .prefixedWith("pcf")
    .bindToCloudFoundryService("wavefront-proxy", true);
wfReporter.start(10,  TimeUnit.SECONDS);

The wavefront-proxy is the name of the wavefront proxy service running in PCF. The Wavefront tile should be used to install the wavefront proxy service. Once the tile is installed, the default name of the wavefront proxy service will be wavefront-proxy.

There are additional overloaded methods available in WavefrontReporter class, which can be used to bind to wavefront proxy (e.g., bindToCloudFoundryService()).

Build and push the application

mvn clean install -DskipTests
cf login -a <pcf-api-url> --skip-ssl-validation --sso
cf push wavefront-sample-app -f src/main/resources/manifest.yml -p target/springboot-0.0.1-SNAPSHOT.jar
cf logs wavefront-sample-app --recent

If the manifest does not have wavefront-proxy service info, then the service can be bound to it later using the following commands:

cf bind-service wavefront-sample-app wfproxy-service
cf restage wavefront-sample-app