README

This repo contains the source code and configuration files for the Oracle Cloudnative Labs workshop.

Prerequisites:

• an OKE cluster
• a kubeconfig downloaded and loaded
• helm installed

Install Prometheus

First, we need to install the Prometheus operator on to our cluster. Follow along with:

Prometheus Operator on OKE

The operator gets installed in the monitoring namespace.

kubectl get po --namespace monitoring

NAME                                                    READY     STATUS    RESTARTS   AGE
alertmanager-kube-prometheus-0                          2/2       Running   0          5d
factual-greyhound-prometheus-operator-6674d57cb-jr86m   1/1       Running   0          5d
kube-prometheus-exporter-kube-state-66b8849c9b-kgwck    2/2       Running   0          5d
kube-prometheus-exporter-node-6j69h                     1/1       Running   0          5d
kube-prometheus-exporter-node-92v7k                     1/1       Running   0          5d
kube-prometheus-exporter-node-trzsn                     1/1       Running   0          5d
kube-prometheus-grafana-f869c754-xkjmd                  2/2       Running   0          5d
*prometheus-kube-prometheus-0*                            *3/3*       *Running*   *1*          *5d*

Let's visit the Prometheus dashboard. Where is prometheus located?

kubectl port-forward --namespace=monitoring prometheus-kube-prometheus-0 9090:9090

We've now port forward prometheus to our localhost, which we can now visit. Open your browser here

Investigate alerts, graph and status plus targets.

Play around with the following PromQL query.

http_request_total

Source code

Let's have a look at our application code. Open up main.go in your favorite terminal.

Note that we've imported the Prometheus Go client library:

import (
	"log"
	"net/http"

	"github.com/prometheus/client_golang/prometheus"
	"github.com/prometheus/client_golang/prometheus/promauto"
	"github.com/prometheus/client_golang/prometheus/promhttp"
)```

var ( requests = promauto.NewCounter( prometheus.CounterOpts{ Name: "hello_worlds_total", Help: "Hello Worlds requests.", }) )

This adds a basic counter.


Which we increment in our HTTP handler:

func handler(w http.ResponseWriter, r *http.Request) { requests.Inc() w.Write([]byte("Hello, is it me you're looking for?")) }

We've now instrumented our code for prometheus.

## Build with Wercker

build yaml

box: golang:1.11 build: base-path: /go/src/github.com/mies/workshop-web steps: - script: name: install govendor code: go get -u github.com/kardianos/govendor

- script:
    name: install dependencies
    code: govendor sync

- script:
    name: go vet
    code: govendor vet +local

# - golint:
#     exclude: vendor

- script:
    name: go test
    code: govendor test -v +local

- script:
    name: go build
    code: |
        ls -la
        go build
        ls -la

## Push Docker image to OCIR
push yaml

push-release: steps: - script: name: prepare code: | ls -la / ls -la #mv workshop-web /workshop-web ls -la /

- internal/docker-push:
    ports: "8080"
    working-dir: /pipeline/source
    cmd: ./workshop-web
    env: "CI=true"
    username: $DOCKER_USERNAME
    password: $DOCKER_PASSWORD
    repository: $DOCKER_REPO
    registry: https://iad.ocir.io/v2

## Kubernetes manifest for deployment and monitoring

kind: Service apiVersion: v1 metadata: name: workshop-web labels: app: workshop-web annotations: prometheus.io/scrape: "true" prometheus.io/port: "8080" spec: type: NodePort selector: app: workshop-web ports:

• port: 8080 targetPort: 8080 name: http

---

kind: Deployment apiVersion: extensions/v1beta1 metadata: name: workshop-web spec: replicas: 1 template: metadata: labels: app: workshop-web version: v1 spec: containers: - name: workshop-web image: iad.ocir.io/oracle-cloudnative/workshop-web imagePullPolicy: Always ports: - containerPort: 8080

apiVersion: monitoring.coreos.com/v1 kind: ServiceMonitor metadata: name: workshop-web namespace: monitoring labels: prometheus: kube-prometheus spec: endpoints:

• interval: 30s port: http jobLabel: workshop-web namespaceSelector: matchNames:
  • default selector: matchLabels: app: workshop-web

Not that we've added a new Object to our deployment manifest called `ServiceMonitor`.

## Manual deploy to OKE

`kubectl create -f app.yaml`

Figure out our pod

kubectl get po

kubectl port-forward workshop-web-XXXXXXX-XXXX 8080:8080

proxy and curl our app


## Querying Prometheus


```kubectl get svc --namespace monitoring

NAME                                  TYPE           CLUSTER-IP      EXTERNAL-IP     PORT(S)             AGE
alertmanager-operated                 ClusterIP      None            <none>          9093/TCP,6783/TCP   5d
kube-prometheus                       NodePort       10.96.19.37     <none>          9090:31941/TCP      5d
kube-prometheus-alertmanager          ClusterIP      10.96.58.27     <none>          9093/TCP            5d
kube-prometheus-exporter-kube-state   ClusterIP      10.96.200.208   <none>          80/TCP              5d
kube-prometheus-exporter-node         ClusterIP      10.96.122.238   <none>          9100/TCP            5d
kube-prometheus-grafana               LoadBalancer   10.96.55.98     XXX.XXX.XXX.X   80:30239/TCP        5d
prometheus-operated                   ClusterIP      None            <none>          9090/TCP            5d

Adding a dashboard to Grafana

Log in with admin/admin

Create dashboard fill in query show graph hit url show graph

Profit

foo

---

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Licensed under the Apache License, Version 2.0 (the "License");

you may not use this file except in compliance with the License.

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http://www.apache.org/licenses/LICENSE-2.0

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distributed under the License is distributed on an "AS IS" BASIS,

WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

See the License for the specific language governing permissions and

limitations under the License.