Kubernetes Deployment YAML Generator & Manifest Builder

apiVersion: apps/v1
kind: Deployment
metadata:
  name: web-api-gateway
  namespace: production
  labels:
    app: "web-api-gateway"
    tier: "backend"
    env: "production"
  annotations:
    prometheus.io/scrape: "true"
    prometheus.io/port: "8080"
    prometheus.io/path: "/metrics"
spec:
  replicas: 3
  selector:
    matchLabels:
      app: "web-api-gateway"
  strategy:
    type: RollingUpdate
    rollingUpdate:
      maxSurge: 25%
      maxUnavailable: 0
  minReadySeconds: 5
  template:
    metadata:
      labels:
        app: "web-api-gateway"
        tier: "backend"
        env: "production"
      annotations:
        prometheus.io/scrape: "true"
        prometheus.io/port: "8080"
        prometheus.io/path: "/metrics"
    spec:
      serviceAccountName: web-api-sa
      securityContext:
        runAsNonRoot: true
        runAsUser: 10001
        runAsGroup: 10001
      containers:
      - name: api-server
        image: ghcr.io/acme-corp/api-gateway:v2.4.1
        imagePullPolicy: IfNotPresent
        ports:
        - name: http
          containerPort: 8080
          protocol: TCP
        - name: metrics
          containerPort: 9090
          protocol: TCP
        securityContext:
          readOnlyRootFilesystem: true
          allowPrivilegeEscalation: false
          capabilities:
            drop:
            - ALL
        resources:
          requests:
            cpu: "250m"
            memory: "256Mi"
            ephemeral-storage: "50Mi"
          limits:
            cpu: "1000m"
            memory: "512Mi"
            ephemeral-storage: "200Mi"
        livenessProbe:
          httpGet:
            path: /healthz
            port: 8080
          initialDelaySeconds: 15
          periodSeconds: 10
          timeoutSeconds: 3
          successThreshold: 1
          failureThreshold: 3
        readinessProbe:
          httpGet:
            path: /ready
            port: 8080
          initialDelaySeconds: 5
          periodSeconds: 5
          timeoutSeconds: 2
          successThreshold: 1
          failureThreshold: 2
        env:
        - name: NODE_ENV
          value: "production"
        - name: PORT
          value: "8080"
        - name: DB_PASSWORD
          valueFrom:
            secretKeyRef:
              name: db-credentials
              key: password
        - name: CONFIG_JSON
          valueFrom:
            configMapKeyRef:
              name: app-config
              key: settings.json
        volumeMounts:
        - name: tmp-cache
          mountPath: /tmp
      volumes:
      - name: tmp-cache
        emptyDir: {}
      nodeSelector:
        kubernetes.io/os: "linux"
      affinity:
        podAntiAffinity:
          preferredDuringSchedulingIgnoredDuringExecution:
          - weight: 100
            podAffinityTerm:
              labelSelector:
                matchExpressions:
                - key: app
                  operator: In
                  values:
                  - "web-api-gateway"
              topologyKey: "kubernetes.io/hostname"