# Build stage
FROM mcr.microsoft.com/dotnet/sdk:8.0 AS build
WORKDIR /src
COPY ["Api/Api.csproj", "Api/"]
RUN dotnet restore "Api/Api.csproj"
COPY . .
WORKDIR "/src/Api"
RUN dotnet build "Api.csproj" -c Release -o /app/build
 
# Publish stage
FROM build AS publish
RUN dotnet publish "Api.csproj" -c Release -o /app/publish
 
# Runtime stage
FROM mcr.microsoft.com/dotnet/aspnet:8.0 AS final
WORKDIR /app
COPY --from=publish /app/publish .
ENTRYPOINT ["dotnet", "Api.dll"]

FROM mcr.microsoft.com/dotnet/sdk:8.0 AS build
# ... build steps
 
FROM mcr.microsoft.com/dotnet/aspnet:8.0 AS runtime
# ... runtime steps

apiVersion: apps/v1
kind: Deployment
metadata:
  name: dotnet-api
spec:
  replicas: 3
  selector:
    matchLabels:
      app: dotnet-api
  template:
    metadata:
      labels:
        app: dotnet-api
    spec:
      containers:
      - name: api
        image: myregistry.azurecr.io/dotnet-api:latest
        ports:
        - containerPort: 8080
        env:
        - name: ASPNETCORE_ENVIRONMENT
          value: "Production"
        - name: ConnectionStrings__DefaultConnection
          valueFrom:
            secretKeyRef:
              name: app-secrets
              key: connection-string
        resources:
          requests:
            memory: "256Mi"
            cpu: "250m"
          limits:
            memory: "512Mi"
            cpu: "500m"
        livenessProbe:
          httpGet:
            path: /health
            port: 8080
          initialDelaySeconds: 30
          periodSeconds: 10
        readinessProbe:
          httpGet:
            path: /ready
            port: 8080
          initialDelaySeconds: 10
          periodSeconds: 5

apiVersion: v1
kind: Service
metadata:
  name: dotnet-api-service
spec:
  selector:
    app: dotnet-api
  ports:
  - protocol: TCP
    port: 80
    targetPort: 8080
  type: LoadBalancer

// Program.cs
builder.Services.AddHealthChecks()
    .AddCheck("liveness", () => HealthCheckResult.Healthy())
    .AddCheck("readiness", () => 
    {
        // Check database connectivity, external dependencies
        return HealthCheckResult.Healthy();
    });
 
app.MapHealthChecks("/health");
app.MapHealthChecks("/ready", new HealthCheckOptions
{
    Predicate = check => check.Tags.Contains("readiness")
});

apiVersion: v1
kind: ConfigMap
metadata:
  name: app-config
data:
  appsettings.json: |
    {
      "Logging": {
        "LogLevel": "Information"
      },
      "AllowedHosts": "*"
    }

apiVersion: v1
kind: Secret
metadata:
  name: app-secrets
type: Opaque
data:
  connection-string: <base64-encoded-value>

// Load from environment variables (Kubernetes injects these)
var connectionString = Environment.GetEnvironmentVariable("ConnectionStrings__DefaultConnection");
 
// Or use IConfiguration
var connectionString = configuration.GetConnectionString("DefaultConnection");

apiVersion: autoscaling/v2
kind: HorizontalPodAutoscaler
metadata:
  name: dotnet-api-hpa
spec:
  scaleTargetRef:
    apiVersion: apps/v1
    kind: Deployment
    name: dotnet-api
  minReplicas: 2
  maxReplicas: 10
  metrics:
  - type: Resource
    resource:
      name: cpu
      target:
        type: Utilization
        averageUtilization: 70
  - type: Resource
    resource:
      name: memory
      target:
        type: Utilization
        averageUtilization: 80

// Use Serilog for structured logging
builder.Host.UseSerilog((context, configuration) =>
{
    configuration
        .ReadFrom.Configuration(context.Configuration)
        .Enrich.FromLogContext()
        .WriteTo.Console()
        .WriteTo.Seq("http://seq-service:5341");
});

// Prometheus metrics
builder.Services.AddSingleton<IMetricsFactory, PrometheusMetricsFactory>();
app.UseMetricServer(); // Exposes /metrics endpoint

spec:
  strategy:
    type: RollingUpdate
    rollingUpdate:
      maxSurge: 1
      maxUnavailable: 0

# View pods
kubectl get pods
 
# View logs
kubectl logs <pod-name>
 
# Describe pod
kubectl describe pod <pod-name>
 
# Execute command in pod
kubectl exec -it <pod-name> -- /bin/bash