Monitoring client proxy (#5)

* Adding the proxy client code base + dockerfile

* Add the Helm chart for proxy client

* Delete workflows

* Changes on global variables,
metric type,
error handling, and channels for graceful shutdown

* Change checkProxy function to accept context,
Changes on ticker function

* Mostly change on ticker loop

* Final changes for client proxy

* Changes on checkproxy func client,
Add log for successMetric.Inc()

* Fix doecker image tag issue on image workflow

* Delete workflows

---------

Co-authored-by: Mahsa <[email protected]>

clients/proxy-client/Dockerfile

@@ -0,0 +1,19 @@
+FROM golang:alpine AS builder
+
+WORKDIR /go/src/app
+
+COPY . .
+
+RUN go build -o app
+
+FROM alpine:latest
+
+WORKDIR /app
+
+COPY --from=builder /go/src/app/app .
+
+ENV PROXY_URL="The proxy URL goes here."
+
+EXPOSE 8080
+
+CMD ["./app"]

clients/proxy-client/deploy/Chart.yaml

@@ -0,0 +1,7 @@
+apiVersion: v2
+name: snappcloud-proxy-client
+description: A Helm chart for Kubernetes
+
+type: application
+version: 0.1.0
+appVersion: "0.0.1"

clients/proxy-client/deploy/templates/deployment.yaml

@@ -0,0 +1,46 @@
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: {{ include "snappcloud-proxy-client.fullname" . }}
+  labels:
+    {{- include "snappcloud-proxy-client.labels" . | nindent 4 }}
+spec:
+  replicas: {{ .Values.replicaCount }}
+  selector:
+    matchLabels:
+      {{- include "snappcloud-proxy-client.selectorLabels" . | nindent 6 }}
+  template:
+    metadata:
+      labels:
+        {{- include "snappcloud-proxy-client.selectorLabels" . | nindent 8 }}
+      annotations:
+        {{- .Values.podAnnotations | toYaml | nindent 8 }}
+    spec:
+      serviceAccountName: {{ include "snappcloud-proxy-client.serviceAccountName" . }}
+      securityContext:
+        {{- toYaml .Values.podSecurityContext | nindent 8 }}
+      containers:
+        - name: {{ .Chart.Name }}
+          securityContext:
+            {{- toYaml .Values.securityContext | nindent 12 }}
+          image: "{{ .Values.image.repository }}:{{ .Values.image.tag }}"
+          imagePullPolicy: {{ .Values.image.pullPolicy }}
+          ports:
+            - name: http
+              containerPort: 80
+              protocol: TCP
+          env:
+            - name: PROXY_URL
+              valueFrom:
+                secretKeyRef:
+                  name: {{ .Values.configSecretName }}
+                  key: PROXY_URL
+          {{ .Values.nodeSelector | toYaml | nindent 8 }}
+      tolerations:
+        {{- with .Values.tolerations }}
+        {{- toYaml . | nindent 8 }}
+        {{- end }}
+      affinity:
+        {{- with .Values.affinity }}
+        {{- toYaml . | nindent 8 }}
+        {{- end }}

clients/proxy-client/deploy/templates/secret.yaml

@@ -0,0 +1,9 @@
+apiVersion: v1
+kind: Secret
+metadata:
+  name: {{ .Values.configSecretName }}
+  labels:
+    {{- include "snappcloud-proxy-client.labels" . | nindent 4 }}
+type: Opaque
+stringData:
+  PROXY_URL: "The proxy address."

clients/proxy-client/deploy/templates/service.yaml

@@ -0,0 +1,14 @@
+apiVersion: v1
+kind: Service
+metadata:
+  name: {{ include "snappcloud-proxy-client.fullname" . }}
+  labels:
+    {{- include "snappcloud-proxy-client.labels" . | nindent 4 }}
+spec:
+  type: {{ .Values.service.type }}
+  ports:
+    - port: {{ .Values.service.port }}
+      targetPort: http
+      protocol: TCP
+  selector:
+    {{- include "snappcloud-proxy-client.selectorLabels" . | nindent 4 }}

clients/proxy-client/deploy/values.yaml

@@ -0,0 +1,37 @@
+replicaCount: 1
+
+image:
+  repository: ghcr.io/snapp-incubator/snappcloud-status-backend
+  pullPolicy: Always
+  tag: "0.0.1"
+
+imagePullSecrets: []
+nameOverride: ""
+fullnameOverride: ""
+
+serviceAccount:
+  create: false
+  automount: true
+  annotations: {}
+  name: ""
+
+service:
+  type: ClusterIP
+  port: 8080
+
+resources:
+  limits:
+    cpu: 100m
+    memory: 128Mi
+  requests:
+    cpu: 100m
+    memory: 128Mi
+
+autoscaling:
+  enabled: false
+  minReplicas: 1
+  maxReplicas: 100
+  targetCPUUtilizationPercentage: 80
+  # targetMemoryUtilizationPercentage: 80
+
+configSecretName: spcld-proxy-health-client

clients/proxy-client/go.mod

@@ -0,0 +1,16 @@
+module github.com/snapp-incubator/snappcloud-status-backend/clients/proxy-client
+
+go 1.21.0
+
+require github.com/prometheus/client_golang v1.18.0
+
+require (
+	github.com/beorn7/perks v1.0.1 // indirect
+	github.com/cespare/xxhash/v2 v2.2.0 // indirect
+	github.com/matttproud/golang_protobuf_extensions/v2 v2.0.0 // indirect
+	github.com/prometheus/client_model v0.5.0 // indirect
+	github.com/prometheus/common v0.45.0 // indirect
+	github.com/prometheus/procfs v0.12.0 // indirect
+	golang.org/x/sys v0.15.0 // indirect
+	google.golang.org/protobuf v1.31.0 // indirect
+)

clients/proxy-client/go.sum

@@ -0,0 +1,26 @@
+github.com/beorn7/perks v1.0.1 h1:VlbKKnNfV8bJzeqoa4cOKqO6bYr3WgKZxO8Z16+hsOM=
+github.com/beorn7/perks v1.0.1/go.mod h1:G2ZrVWU2WbWT9wwq4/hrbKbnv/1ERSJQ0ibhJ6rlkpw=
+github.com/cespare/xxhash/v2 v2.2.0 h1:DC2CZ1Ep5Y4k3ZQ899DldepgrayRUGE6BBZ/cd9Cj44=
+github.com/cespare/xxhash/v2 v2.2.0/go.mod h1:VGX0DQ3Q6kWi7AoAeZDth3/j3BFtOZR5XLFGgcrjCOs=
+github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
+github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/golang/protobuf v1.5.0/go.mod h1:FsONVRAS9T7sI+LIUmWTfcYkHO4aIWwzhcaSAoJOfIk=
+github.com/google/go-cmp v0.5.5/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
+github.com/google/go-cmp v0.5.9 h1:O2Tfq5qg4qc4AmwVlvv0oLiVAGB7enBSJ2x2DqQFi38=
+github.com/google/go-cmp v0.5.9/go.mod h1:17dUlkBOakJ0+DkrSSNjCkIjxS6bF9zb3elmeNGIjoY=
+github.com/matttproud/golang_protobuf_extensions/v2 v2.0.0 h1:jWpvCLoY8Z/e3VKvlsiIGKtc+UG6U5vzxaoagmhXfyg=
+github.com/matttproud/golang_protobuf_extensions/v2 v2.0.0/go.mod h1:QUyp042oQthUoa9bqDv0ER0wrtXnBruoNd7aNjkbP+k=
+github.com/prometheus/client_golang v1.18.0 h1:HzFfmkOzH5Q8L8G+kSJKUx5dtG87sewO+FoDDqP5Tbk=
+github.com/prometheus/client_golang v1.18.0/go.mod h1:T+GXkCk5wSJyOqMIzVgvvjFDlkOQntgjkJWKrN5txjA=
+github.com/prometheus/client_model v0.5.0 h1:VQw1hfvPvk3Uv6Qf29VrPF32JB6rtbgI6cYPYQjL0Qw=
+github.com/prometheus/client_model v0.5.0/go.mod h1:dTiFglRmd66nLR9Pv9f0mZi7B7fk5Pm3gvsjB5tr+kI=
+github.com/prometheus/common v0.45.0 h1:2BGz0eBc2hdMDLnO/8n0jeB3oPrt2D08CekT0lneoxM=
+github.com/prometheus/common v0.45.0/go.mod h1:YJmSTw9BoKxJplESWWxlbyttQR4uaEcGyv9MZjVOJsY=
+github.com/prometheus/procfs v0.12.0 h1:jluTpSng7V9hY0O2R9DzzJHYb2xULk9VTR1V1R/k6Bo=
+github.com/prometheus/procfs v0.12.0/go.mod h1:pcuDEFsWDnvcgNzo4EEweacyhjeA9Zk3cnaOZAZEfOo=
+golang.org/x/sys v0.15.0 h1:h48lPFYpsTvQJZF4EKyI4aLHaev3CxivZmv7yZig9pc=
+golang.org/x/sys v0.15.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
+golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
+google.golang.org/protobuf v1.26.0-rc.1/go.mod h1:jlhhOSvTdKEhbULTjvd4ARK9grFBp09yW+WbY/TyQbw=
+google.golang.org/protobuf v1.31.0 h1:g0LDEJHgrBl9N9r17Ru3sqWhkIx2NB67okBHPwC7hs8=
+google.golang.org/protobuf v1.31.0/go.mod h1:HV8QOd/L58Z+nl8r43ehVNZIU/HEI6OcFqwMG9pJV4I=

clients/proxy-client/main.go

@@ -0,0 +1,120 @@
+package main
+
+import (
+	"context"
+	"log"
+	"net/http"
+	"net/url"
+	"os"
+	"os/signal"
+	"sync"
+	"syscall"
+	"time"
+
+	"github.com/prometheus/client_golang/prometheus"
+	"github.com/prometheus/client_golang/prometheus/promhttp"
+)
+
+var (
+	successMetric = prometheus.NewCounter(prometheus.CounterOpts{
+		Name: "proxy_check_success",
+		Help: "Indicates the number of successful proxy checks",
+	})
+)
+
+func init() {
+	prometheus.MustRegister(successMetric)
+}
+
+func checkProxy(ctx context.Context, proxyURL, targetURL string) {
+	transport, _ := http.DefaultTransport.(*http.Transport)
+	transport.Proxy = http.ProxyURL(mustParseURL(proxyURL))
+
+	client := &http.Client{
+		Transport: transport,
+	}
+
+	req, err := http.NewRequestWithContext(ctx, "GET", targetURL, nil)
+	if err != nil {
+		log.Printf("Error creating HTTP request: %s\n", err)
+		return
+	}
+
+	resp, err := client.Do(req)
+	if err != nil {
+		log.Printf("Error performing HTTP request: %s\n", err)
+		return
+	}
+	defer resp.Body.Close()
+
+	if resp.StatusCode == http.StatusOK {
+		successMetric.Inc()
+		log.Printf("Proxy check succeed, Healthy status.")
+	} else {
+		log.Printf("Proxy check failed. Status code: %d\n", resp.StatusCode)
+	}
+}
+
+func mustParseURL(rawURL string) *url.URL {
+	u, err := url.Parse(rawURL)
+	if err != nil {
+		panic(err)
+	}
+	return u
+}
+
+func main() {
+	proxyURL := os.Getenv("PROXY_URL")
+	if proxyURL == "" {
+		log.Fatal("PROXY_URL environment variable not set")
+	}
+	targetURL := "https://ifconfig.me"
+
+	http.Handle("/metrics", promhttp.Handler())
+
+	server := &http.Server{
+		Addr: ":9090",
+	}
+
+	var wg sync.WaitGroup
+
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+
+	signalCh := make(chan os.Signal, 1)
+	signal.Notify(signalCh, syscall.SIGINT, syscall.SIGTERM)
+
+	go func() {
+		<-signalCh
+		log.Println("Received signal, shutting down gracefully...")
+		cancel()
+		server.Shutdown(ctx)
+	}()
+
+	wg.Add(1)
+	go func() {
+		defer wg.Done()
+		ticker := time.NewTicker(5 * time.Minute)
+		defer ticker.Stop()
+
+		for {
+			select {
+			case <-ctx.Done():
+				log.Println("Ticker routine shutting down...")
+				return
+			case <-ticker.C:
+				checkProxy(ctx, proxyURL, targetURL)
+			}
+		}
+	}()
+
+	wg.Add(1)
+	go func() {
+		defer wg.Done()
+		log.Fatal(server.ListenAndServe())
+	}()
+
+	log.Println("Waiting for the HTTP server to finish...")
+	wg.Wait()
+	log.Println("All goroutines shut down. Exiting.")
+}