Dockerfile

# Build stage
FROM golang:1.21-alpine AS builder

# Install dependencies
RUN apk add --no-cache git ca-certificates

# Set working directory
WORKDIR /app

# Copy go mod files
COPY go.mod go.sum ./

# Download dependencies
RUN go mod download

# Copy source code
COPY . .

# Build the binary
RUN CGO_ENABLED=0 GOOS=linux go build -a -installsuffix cgo -o pod-limit-checker .

# Runtime stage
FROM alpine:latest

# Install CA certificates for SSL
RUN apk --no-cache add ca-certificates

# Create non-root user
RUN addgroup -S appgroup && adduser -S appuser -G appgroup

# Set working directory
WORKDIR /app

# Copy binary from builder
COPY --from=builder /app/pod-limit-checker .

# Copy kubeconfig template (if needed)
# COPY --from=builder /app/kubeconfig.template /app/kubeconfig.template

# Set permissions
RUN chown -R appuser:appgroup /app

# Switch to non-root user
USER appuser

# Set entrypoint
ENTRYPOINT ["/app/pod-limit-checker"]