# ───── Stage 1: Build the adapter binary ─────
FROM golang:1.22-alpine AS builder

RUN apk add --no-cache git make gcc musl-dev

WORKDIR /src
COPY . .

# Fix missing go.sum entries
RUN go mod tidy

# Build (default target = all)
RUN make

# Verify binary exists and is executable — no --version check
RUN ls -la postgresql-prometheus-adapter && \
    ./postgresql-prometheus-adapter --help > /dev/null


# ───── Stage 2: Runtime (Alpine = has glibc + loader) ─────
FROM alpine:3.20

# Install only what the binary needs (tiny)
RUN apk add --no-cache libc6-compat

COPY --from=builder /src/postgresql-prometheus-adapter /usr/local/bin/postgresql-prometheus-adapter

# Make sure it's executable (just in case)
RUN chmod +x /usr/local/bin/postgresql-prometheus-adapter

USER 1001:1001

EXPOSE 9201

HEALTHCHECK --interval=30s --timeout=3s --start-period=5s --retries=3 \
  CMD ["wget", "--spider", "-q", "http://127.0.0.1:9201/health"] || exit 1

ENTRYPOINT ["/usr/local/bin/postgresql-prometheus-adapter"]