Merge pull request #151 from marcel-dempers/servicemonitors

servicemonitors

kubernetes/servicemonitors/README.md

@@ -0,0 +1,110 @@
+# Introduction to Service Monitors
+
+In order to understand service monitors, we will need to understand how to monitor 
+kubernetes environment. </br>
+You will need a base understanding of Kubernetes and have a basic understanding of the `kube-prometheus` monitoring stack. </br>
+
+Checkout the video [How to monitor Kubernetes in 2022](https://youtu.be/YDtuwlNTzRc): 
+
+<a href="https://youtu.be/YDtuwlNTzRc" title="Monitoring Kubernetes"><img src="https://i.ytimg.com/vi/YDtuwlNTzRc/hqdefault.jpg" width="50%" alt="Monitoring Kubernetes" /></a>
+
+
+## Create a kubernetes cluster
+
+```
+# create cluster
+kind create cluster --name monitoring --image kindest/node:v1.23.5
+
+# see cluster up and running
+kubectl get nodes
+NAME                  STATUS   ROLES                  AGE     VERSION
+monitoring-control-plane   Ready    control-plane,master   2m12s   v1.23.5
+```
+
+## Deploy kube-prometheus
+
+Installation: 
+
+```
+kubectl create -f ./monitoring/prometheus/kubernetes/1.23/manifests/setup/
+kubectl create -f ./monitoring/prometheus/kubernetes/1.23/manifests/
+```
+
+Check the install:
+
+```
+kubectl -n monitoring get pods
+```
+
+After a few minutes, everything should be up and running:
+
+```
+kubectl -n monitoring get pods
+NAME                                   READY   STATUS    RESTARTS   AGE
+alertmanager-main-0                    2/2     Running   0          3m10s
+alertmanager-main-1                    2/2     Running   0          3m10s
+alertmanager-main-2                    2/2     Running   0          3m10s
+blackbox-exporter-6b79c4588b-t4czf     3/3     Running   0          4m7s
+grafana-7fd69887fb-zm2d2               1/1     Running   0          4m7s
+kube-state-metrics-55f67795cd-f7frb    3/3     Running   0          4m6s
+node-exporter-xjdtn                    2/2     Running   0          4m6s
+prometheus-adapter-85664b6b74-bvmnj    1/1     Running   0          4m6s
+prometheus-adapter-85664b6b74-mcgbz    1/1     Running   0          4m6s
+prometheus-k8s-0                       2/2     Running   0          3m9s
+prometheus-k8s-1                       2/2     Running   0          3m9s
+prometheus-operator-6dc9f66cb7-z98nj   2/2     Running   0          4m6s
+```
+
+## View dashboards
+
+```
+kubectl -n monitoring port-forward svc/grafana 3000
+```
+
+Then access Grafana on [localhost:3000](http://localhost:3000)
+
+## Access Prometheus 
+
+```
+kubectl -n monitoring port-forward svc/prometheus-operated 9090
+```
+
+Then access Prometheus on [localhost:9090](http://localhost:9090).
+
+## Create our own Prometheus 
+
+
+```
+kubectl apply -n monitoring -f ./kubernetes/servicemonitors/prometheus.yaml
+
+```
+
+View our prometheus `prometheus-applications-0` instance:
+
+```
+kubectl -n monitoring get pods
+```
+
+Checkout our prometheus UI
+
+```
+kubectl -n monitoring port-forward prometheus-applications-0 9090
+```
+
+## Deploy a service monitor for example app
+
+```
+kubectl -n default apply -f ./kubernetes/servicemonitors/servicemonitor.yaml
+```
+
+After applying the service monitor, if Prometheus is correctly selecting it, we should see the item appear under the [Service Discovery](http://localhost:9090/service-discovery) page in Prometheus. </br>
+Double check with with `port-forward` before proceeding. </br>
+If it does not appear, that means your Prometheus instance is not selecting the service monitor accordingly. Either a label mismatch on the namespace or the service monitor. </br>
+
+## Deploy our example app
+
+```
+kubectl -n default apply -f kubernetes\servicemonitors\example-app\
+```
+
+Now we should see a target in the Prometheus [Targets](http://localhost:9090/targets) page. </br>

kubernetes/servicemonitors/example-app/deployment.yaml

@@ -0,0 +1,27 @@
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: example-deploy
+  labels:
+    app: example-app
+spec:
+  selector:
+    matchLabels:
+      app: example-app
+  replicas: 2
+  strategy:
+    type: RollingUpdate
+    rollingUpdate:
+      maxSurge: 1
+      maxUnavailable: 0
+  template:
+    metadata:
+      labels:
+        app: example-app
+    spec:
+      containers:
+      - name: example-app
+        image: aimvector/python:metrics
+        imagePullPolicy: Always
+        ports:
+        - containerPort: 5000

kubernetes/servicemonitors/example-app/service.yaml

@@ -0,0 +1,15 @@
+apiVersion: v1
+kind: Service
+metadata:
+  name: example-service
+  labels:
+    app: example-app
+spec:
+  type: ClusterIP
+  selector:
+    app: example-app
+  ports:
+    - protocol: TCP
+      name: web
+      port: 80
+      targetPort: 5000

kubernetes/servicemonitors/prometheus.yaml

@@ -0,0 +1,31 @@
+apiVersion: monitoring.coreos.com/v1
+kind: Prometheus
+metadata:
+  labels:
+    app.kubernetes.io/component: prometheus
+    app.kubernetes.io/instance: k8s
+    app.kubernetes.io/name: prometheus
+    app.kubernetes.io/part-of: kube-prometheus
+    app.kubernetes.io/version: 2.32.1
+  name: applications
+  namespace: monitoring
+spec:
+  image: quay.io/prometheus/prometheus:v2.32.1
+  nodeSelector:
+    kubernetes.io/os: linux
+  replicas: 1
+  resources:
+    requests:
+      memory: 400Mi
+  ruleSelector: {}
+  securityContext:
+    fsGroup: 2000
+    runAsNonRoot: true
+    runAsUser: 1000
+  serviceAccountName: prometheus-k8s
+  #serviceMonitorNamespaceSelector: {} #match all namespaces
+  serviceMonitorNamespaceSelector:
+    matchLabels:
+      kubernetes.io/metadata.name: default
+  serviceMonitorSelector: {} #match all servicemonitors
+  version: 2.32.1

kubernetes/servicemonitors/servicemonitor.yaml

@@ -0,0 +1,13 @@
+apiVersion: monitoring.coreos.com/v1
+kind: ServiceMonitor
+metadata:
+  labels:
+  name: example-app
+  namespace: default
+spec:
+  endpoints:
+  - interval: 30s
+    port: web
+  selector:
+    matchLabels:
+      app: example-app

monitoring/prometheus/python-application/dockerfile

@@ -1,4 +1,4 @@
-FROM python:3.7.3-alpine3.9 as prod
+FROM python:3.10.5-alpine3.16 as prod
 
 RUN mkdir /app/
 WORKDIR /app/

monitoring/prometheus/python-application/src/requirements.txt

@@ -1,2 +1,2 @@
-Flask == 1.0.3
-prometheus_client == 0.7.1
+Flask == 2.1.2
+prometheus_client == 0.14.1