Create a telemetry server

Create a server that receives telemetry events from the Che telemetry plugin and writes them to standard output. For production, consider integrating with a third-party telemetry system such as Segment or Woopra.

Prerequisites

You have a running instance of Eclipse Che.

Procedure

Create a main.go file for a Go application that starts a server on port 8080 and writes events to standard output:

package main

import (
	"io/ioutil"
	"net/http"

	"go.uber.org/zap"
)

var logger *zap.SugaredLogger

func event(w http.ResponseWriter, req *http.Request) {
	switch req.Method {
	case "GET":
		logger.Info("GET /event")
	case "POST":
		logger.Info("POST /event")
	}
	body, err := req.GetBody()
	if err != nil {
		logger.With("err", err).Info("error getting body")
		return
	}
	responseBody, err := ioutil.ReadAll(body)
	if err != nil {
		logger.With("error", err).Info("error reading response body")
		return
	}
	logger.With("body", string(responseBody)).Info("got event")
}

func activity(w http.ResponseWriter, req *http.Request) {
	switch req.Method {
	case "GET":
		logger.Info("GET /activity, doing nothing")
	case "POST":
		logger.Info("POST /activity")
		body, err := req.GetBody()
		if err != nil {
			logger.With("error", err).Info("error getting body")
			return
		}
		responseBody, err := ioutil.ReadAll(body)
		if err != nil {
			logger.With("error", err).Info("error reading response body")
			return
		}
		logger.With("body", string(responseBody)).Info("got activity")
	}
}

func main() {

	log, _ := zap.NewProduction()
	logger = log.Sugar()

	http.HandleFunc("/event", event)
	http.HandleFunc("/activity", activity)
	logger.Info("Added Handlers")

	logger.Info("Starting to serve")
	http.ListenAndServe(":8080", nil)
}

Create a container image based on this code and expose it as a deployment in Kubernetes in the eclipse-che namespace. Clone the repository and build the container:

$ git clone https://github.com/che-incubator/telemetry-server-example
$ cd telemetry-server-example
$ docker build -t registry/organization/telemetry-server-example:latest .
$ docker push registry/organization/telemetry-server-example:latest

Deploy the telemetry server to Kubernetes.

Both manifest_with_ingress.yaml and manifest_with_route contain definitions for a Deployment and Service. The former also defines a Kubernetes Ingress, while the latter defines an Kubernetes Route.

In the manifest file, replace the image and host fields to match the image you pushed, and the public hostname of your Kubernetes cluster. Then run:
```
$ kubectl apply -f manifest_with_[ingress|route].yaml -n eclipse-che
```

Verification

Verify that the telemetry server pod is running:

kubectl get pods -n eclipse-che -l app=telemetry-server-example

Additional resources