Eureka Prometheus Aggregator and Exporter

Experimental project for collecting metrics from Netflix Eureka attached application instances running inside of Kubernetes cluster.

The goal is to collect metrics outside of Kubernetes (external monitoring).

Overview

                          +---------------------------------------------------------+
                          |Kubernetes cluster                                       |
                          |---------------------------------------------------------|
                          |                                                         |
                          | +---------------+  +---------------+ +----------------+ |
                          | |NS: monitoring |  |NS: staging    | |NS: live        | |
                          | |---------------|  |---------------| |----------------| |
   +------------------+   | |               |  |               | |                | |
   |                  |   | | +-----------+ |  |               | |                | |
   |    Prometheus    +------>|Exporter   +-------------+-----------------+       | |
   |                  |   | | +-----+-----+ |  |        |      | |        |       | |
   +------------------+   | |       |       |  |        |      | |        |       | |
                          | |       |       |  | +------v----+ | | +------v-----+ | |
                          | |       |       |  | |Eureka #1  | | | |Eureka #2   | | |
                          | |       |       |  | +-----------+ | | +------------+ | |
                          | |       |       |  |               | |                | |
                          | |       |       |  | +-----------+ | |                | |
                          | |       +----------->|Service #1 | | |                | |
                          | |               |  | +-----------+ | |                | |
                          | |               |  |               | |                | |
                          | +---------------+  +---------------+ +----------------+ |
                          |                                                         |
                          +---------------------------------------------------------+

• Expose eureka-exporter endpoint either via NodePort or Ingress
• Point Prometheus to eureka-exporter endpoint
• On each Prometheus collect request, eureka-exporter will:
  • Discover Eureka services across all namespaces or configured namespace
  • Call each found Eureka endpoint and collect attached instances
  • For each instance which exposes promethesURI metadata:
    • Collect metrics
  • Relabel all collected metrics (enrich with app, namespace and instanceId labels)
  • Return all collected and relabeled metrics back to Prometheus

Running on minikube

$ minikube start

## deploy system components
$ kubectl create ns prod
$ kubectl apply -f ./demo/cloud-config-service.yml
$ kubectl apply -f ./demo/eureka-service.yml

## wait a little and deploy services
$ kubectl apply -f ./demo/auto-service.yml
$ kubectl apply -f ./demo/moto-service.yml

## check eureka
$ kubectl proxy
$ curl http://localhost:8001/api/v1/namespaces/prod/services/eureka-service:8761/proxy/eureka/apps

## deploy exporter
$ kubectl apply -f ./deployment.yml

## get metrics
$ curl http://$(minikube ip):31000/metrics

Options

> go build
> ./eureka_exporter -h
  -c, --config string      Kubernetes config file path (when running outside of cluster) (default "/Users/user/.kube/config")
  -d, --debug              Display debug output
  -h, --help               Display help
  -l, --listen-port int    Server listen port (default 8080)
  -n, --namespace string   Namespace to search, default: search all
  -s, --selector string    Eureka service selector (default "app=eureka-service")
  -t, --test               Run metric collection write to stdout and exit (requires 'kubectl proxy')
  -o, --timeout int        HTTP call timeout, ms (default 5000)