Dockerfile

# Build stage
FROM golang:1.21-alpine AS builder

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

# Set working directory
WORKDIR /build

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

# Download dependencies
RUN go mod download

# Copy source code
COPY . .

# Build the application with optimizations
RUN CGO_ENABLED=0 GOOS=linux GOARCH=amd64 go build \
    -ldflags='-w -s -extldflags "-static"' \
    -a -installsuffix cgo \
    -o voidprobber \
    main.go

# Final stage
FROM scratch

# Copy ca-certificates for HTTPS requests
COPY --from=builder /etc/ssl/certs/ca-certificates.crt /etc/ssl/certs/

# Copy timezone data
COPY --from=builder /usr/share/zoneinfo /usr/share/zoneinfo

# Copy the binary
COPY --from=builder /build/voidprobber /voidprobber

# Create a non-root user (using numeric ID for scratch)
USER 65534:65534

# Set entrypoint
ENTRYPOINT ["/voidprobber"]

# Add labels for metadata
LABEL maintainer="nullifiedsec"
LABEL description="Take a list of domains and probe for working HTTP and HTTPS servers"
LABEL version="2.0.0"