feat: 채윤희의 서비스 컨테이너 이미지 제작

2025/helm/dst03106/Dockerfile

@@ -0,0 +1,10 @@
+FROM golang:alpine AS builder
+WORKDIR /app
+COPY main.go .
+RUN CGO_ENABLED=0 go build -ldflags="-s -w" -o main main.go
+# -s : (디버거를 위한) 심볼 테이블 제거, -w: 디버깅 정보 제거
+
+FROM scratch
+COPY --from=builder /app/main /main
+
+ENTRYPOINT ["/main"]

2025/helm/dst03106/Makefile

@@ -0,0 +1,40 @@
+CLUSTER_NAME=my-cluster
+APP_NAME=my-app
+NAMESPACE=my-namespace
+CHART_PATH=./charts
+
+.PHONY: all docker-build docker-test create-cluster delete-cluster install helm-debug pod-debug test
+
+all: docker-build create-cluster install test delete-cluster
+
+docker-build:
+	docker build -t $(APP_NAME):latest .
+
+docker-test:
+	make docker-build
+	docker images $(APP_NAME):latest
+	docker run -d -p "8000:8080" --rm --name $(APP_NAME) $(APP_NAME):latest
+	sleep 2
+	curl http://localhost:8000/healthcheck 
+	docker stop $(APP_NAME) 
+
+create-cluster:
+	k3d cluster create ${CLUSTER_NAME} --port "30080:30080@loadbalancer"
+	k3d image import ${APP_NAME}:latest -c ${CLUSTER_NAME}
+	docker exec k3d-${CLUSTER_NAME}-server-0 sh -c 'echo "nameserver 8.8.8.8" > /etc/resolv.conf'
+
+delete-cluster:
+	k3d cluster delete ${CLUSTER_NAME}
+
+install:
+	helm install ${APP_NAME} ${CHART_PATH}/ --wait 
+
+helm-debug:
+	helm template ${CHART_PATH}/ --debug
+
+pod-debug:
+	kubectl describe pod
+
+test:
+	curl http://localhost:30080/api/v1/dst03106
+	curl http://localhost:30080/healthcheck

2025/helm/dst03106/charts/Chart.yaml

@@ -0,0 +1,5 @@
+apiVersion: v2
+name: my-service
+description: A minimal Helm chart for my app
+version: 0.1.0
+appVersion: "1.0"

2025/helm/dst03106/charts/templates/_helpers.tpl

@@ -0,0 +1,7 @@
+{{- define "my-chart.name" -}}
+{{- .Chart.Name -}}
+{{- end -}}
+
+{{- define "my-chart.fullname" -}}
+{{- printf "%s-%s" .Release.Name .Chart.Name | trunc 63 | trimSuffix "-" -}}
+{{- end -}}

2025/helm/dst03106/charts/templates/deployment.yaml

@@ -0,0 +1,34 @@
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: {{ include "my-chart.fullname" . }}
+spec:
+  replicas: {{ .Values.replicaCount }}
+  # Existing ReplicaSets whose pods are selected by this
+  # ... will be the ones affected by this deployment.
+  selector: 
+    matchLabels:
+      app: {{ include "my-chart.name" . }}
+      tier: backend
+    matchExpressions: # ref. https://kubernetes.io/ko/docs/concepts/overview/working-with-objects/labels/
+      - {key : environment, operator: NotIn, values: [dev]}
+  # Template describes the pods that will be created.
+  template:
+    metadata:
+      labels: # labels과 selector는 object 타입
+        app: {{ include "my-chart.name" . }}
+        tier: backend
+        environment: prod
+    spec:
+      containers:
+        - name: {{ .Chart.Name }}
+          image: "{{ .Values.image.name }}"
+          imagePullPolicy: {{ .Values.image.pullPolicy }}
+          env:
+            - name: PORT
+              value: "{{ .Values.service.targetPort }}"
+          ports:
+            - containerPort: {{ .Values.service.targetPort }} # 문서화용 데이터
+              # List of ports to expose from the container. 
+              # Not specifying a port here DOES NOT prevent that port from being exposed. 
+              # Any port which is listening on the default "0.0.0.0" address inside a container will be accessible from the network.

2025/helm/dst03106/charts/templates/service.yaml

@@ -0,0 +1,17 @@
+apiVersion: v1
+kind: Service
+metadata:
+  name: {{ include "my-chart.fullname" . }}
+spec:
+  type: {{ .Values.service.type }}
+  ports:
+    - name: http
+      port: {{ .Values.service.port }}
+      targetPort: {{ .Values.service.targetPort }}
+      {{- if and (or (eq .Values.service.type "NodePort") (eq .Values.service.type "LoadBalancer")) .Values.service.nodePort }}
+      nodePort: {{ .Values.service.nodePort }}
+      {{- end }}
+      protocol: TCP
+  selector: # 어떤 파드에 트래픽을 보낼지 라벨로 선택
+    app: {{ include "my-chart.name" . }}
+    tier: backend

2025/helm/dst03106/charts/values.yaml

@@ -0,0 +1,12 @@
+replicaCount: 1
+
+image:
+  name: my-app:latest
+  pullPolicy: IfNotPresent
+
+service:
+  type: NodePort
+  port: 80 # Service가 제공하는 포트 번호 (클러스터 내부에서 사용)
+  nodePort: 30080 # 클러스터 외부에서 노드 IP를 통해 접근하는 포트 번호
+  targetPort: 8080 # 실제 Pod 내부 컨테이너의 포트 번호
+    # 30080 포트 요청 -> Kubernetes Service (80) -> 선택된 Pod의 컨테이너 내부 포트(8080)으로 전달 

2025/helm/dst03106/main.go

@@ -0,0 +1,38 @@
+package main
+
+import (
+	"fmt"
+	"log"
+	"net/http"
+	"os"
+)
+
+func healthcheckHandler(w http.ResponseWriter, r *http.Request) {
+	w.Header().Set("Content-Type", "application/json")
+	fmt.Fprint(w, `{"status": "ok"}`)
+}
+
+func myHandler(w http.ResponseWriter, r *http.Request) {
+	w.Header().Set("Content-Type", "application/json")
+	fmt.Fprintln(w, `{"message": "Hello world"}`)
+}
+
+func getPort() string {
+	if port := os.Getenv("PORT"); port != "" {
+		return port
+	}
+	return "8080"
+}
+
+func main() {
+	http.HandleFunc("/healthcheck", healthcheckHandler)
+	http.HandleFunc("/api/v1/dst03106", myHandler)
+
+	port := getPort()
+	host := "0.0.0.0"
+	log.Printf("Server running on http://%s:%s\n", host, port)
+	err := http.ListenAndServe(host+":"+port, nil)
+	if err != nil {
+		log.Fatalf("Failed to start server: %v", err)
+	}
+}