# syntax=docker/dockerfile:1.4

# SPDX-FileCopyrightText: Copyright (c) 2025-2026 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
# SPDX-License-Identifier: Apache-2.0

# Supervisor image build.
#
# The final image is `scratch`: it only carries the static `openshell-sandbox`
# binary used by Docker extraction, Podman image volumes, and the Kubernetes
# init container copy-self path. A static musl binary lets the image stay
# `scratch` while still being executable as an init container.
#
# The Rust binary is built natively before this image build runs and staged at:
#   deploy/docker/.build/prebuilt-binaries/<arch>/openshell-sandbox
#
# Use tasks/scripts/docker-build-image.sh supervisor (or `mise run build:docker:supervisor`)
# to stage the binary and build the image in one step. CI builds the binary
# per-architecture via the `rust-native-build.yml` workflow (with the musl
# target) and uploads it as an artifact, which is downloaded into the same
# staging directory before the image build job runs.

FROM scratch AS supervisor

ARG TARGETARCH

# --chmod=0550 drops world-execute and survives the actions/upload-artifact
# + download-artifact roundtrip (which strips exec perms). Ownership is left
# at root (0:0) deliberately: the Podman driver mounts this image as a
# read-only image volume into the sandbox container and drops DAC_OVERRIDE,
# so the container's UID 0 must own the binary to read+exec it. Mode 0550
# (r-xr-x---) is the security win; the chown to a non-root UID was breaking
# Podman without buying anything since the container is always UID 0.
COPY --chmod=0550 deploy/docker/.build/prebuilt-binaries/${TARGETARCH}/openshell-sandbox /openshell-sandbox

ENTRYPOINT ["/openshell-sandbox"]