From b3ac1158ba62dae92be4a92ba64914cf657b22b8 Mon Sep 17 00:00:00 2001
From: xZero707 <aleksandar@puharic.com>
Date: Wed, 12 Mar 2025 02:55:04 +0100
Subject: [PATCH] Refactor, add arch/noarch symlinks, simplify and rebase build
 stages to busybox

---
 Dockerfile        | 93 +++++++++++++++++++++++++----------------------
 Dockerfile.legacy | 10 ++---
 2 files changed, 54 insertions(+), 49 deletions(-)

diff --git a/Dockerfile b/Dockerfile
index c23b43f..8ed882d 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,69 +1,74 @@
 ARG S6_OVERLAY_VERSION="3.2.0.2"
-ARG S6_OVERLAY_RELEASE="https://github.com/just-containers/s6-overlay/releases/download/"
+ARG S6_OVERLAY_RELEASE="https://github.com/just-containers/s6-overlay/releases/download"
 ARG S6_OVERLAY_PAK_EXT=".tar.xz"
 
-# First stage - Download s6-overlay noarch base and unpack it
-FROM scratch AS downloader-s6-base
-ARG S6_OVERLAY_VERSION
-ARG S6_OVERLAY_RELEASE
-ARG S6_OVERLAY_PAK_EXT
-ADD "${S6_OVERLAY_RELEASE}/v${S6_OVERLAY_VERSION}/s6-overlay-noarch${S6_OVERLAY_PAK_EXT}" /s6overlay-base.tar.xz
 
 
-# Second stage - Download s6-overlay platform-dependent binaries and unpack
-FROM alpine:3.21 AS downloader-s6-bin
+# Downloader stage: download s6-overlay base, binary, symlinks and checksums
+FROM busybox AS downloader
 ARG TARGETPLATFORM
 ARG S6_OVERLAY_VERSION
 ARG S6_OVERLAY_RELEASE
 ARG S6_OVERLAY_PAK_EXT
-ARG S6_OVERLAY_RELEASE_URL="${S6_OVERLAY_RELEASE}/v${S6_OVERLAY_VERSION}/s6-overlay-${TARGETPLATFORM}${S6_OVERLAY_PAK_EXT}"
-ARG S6_OVERLAY_HASH_URL="${S6_OVERLAY_RELEASE}/v${S6_OVERLAY_VERSION}/s6-overlay-${TARGETPLATFORM}${S6_OVERLAY_PAK_EXT}.sha256"
+
+# Set environment variables
+ENV BASE_URL="${S6_OVERLAY_RELEASE}/v${S6_OVERLAY_VERSION}/s6-overlay-noarch${S6_OVERLAY_PAK_EXT}"
+ENV BASE_HASH_URL="${BASE_URL}.sha256"
+ENV BIN_URL="${S6_OVERLAY_RELEASE}/v${S6_OVERLAY_VERSION}/s6-overlay-${TARGETPLATFORM}${S6_OVERLAY_PAK_EXT}"
+ENV BIN_HASH_URL="${BIN_URL}.sha256"
+ENV SYMLINKS_ARCH_URL="${S6_OVERLAY_RELEASE}/v${S6_OVERLAY_VERSION}/s6-overlay-symlinks-arch${S6_OVERLAY_PAK_EXT}"
+ENV SYMLINKS_ARCH_HASH_URL="${SYMLINKS_ARCH_URL}.sha256"
+ENV SYMLINKS_NOARCH_URL="${S6_OVERLAY_RELEASE}/v${S6_OVERLAY_VERSION}/s6-overlay-symlinks-noarch${S6_OVERLAY_PAK_EXT}"
+ENV SYMLINKS_NOARCH_HASH_URL="${SYMLINKS_NOARCH_URL}.sha256"
 
 RUN set -eux \
-    && apk add --no-cache wget \
-    && wget -O /s6overlay-bin.tar.xz "$(echo ${S6_OVERLAY_RELEASE_URL} | sed 's/linux\///g' | sed 's/amd64/x86_64/g' | sed 's/arm64/aarch64/g' | sed 's/arm\/v7/armhf/g')"
+    # Replace platform
+    && BIN_URL_FIXED=$(echo "${BIN_URL}" | sed -e 's/linux\///g' -e 's/amd64/x86_64/g' -e 's/arm64/aarch64/g' -e 's|arm/v7|armhf|g') \
+    && BIN_HASH_URL_FIXED=$(echo "${BIN_HASH_URL}" | sed -e 's/linux\///g' -e 's/amd64/x86_64/g' -e 's/arm64/aarch64/g' -e 's|arm/v7|armhf|g') \
+    # Download s6-overlay binaries
+    && wget -O /s6overlay-bin.tar.xz "${BIN_URL_FIXED}" \
+    && wget -O /s6overlay-bin.tar.xz.sha256 "${BIN_HASH_URL_FIXED}" \
+    # Download s6-overlay base and its hash
+    && wget -O /s6overlay-base.tar.xz "${BASE_URL}" \
+    && wget -O /s6overlay-base.tar.xz.sha256 "${BASE_HASH_URL}" \
+    # Download s6-overlay symlinks \
+    && wget -O /s6overlay-arch-symlinks.tar.xz "${SYMLINKS_ARCH_URL}" \
+    && wget -O /s6overlay-arch-symlinks.tar.xz.sha256 "${SYMLINKS_ARCH_HASH_URL}" \
+    && wget -O /s6overlay-noarch-symlinks.tar.xz "${SYMLINKS_NOARCH_URL}" \
+    && wget -O /s6overlay-noarch-symlinks.tar.xz.sha256 "${SYMLINKS_NOARCH_HASH_URL}" \
+    # Build SHA256SUMS file
+    && echo "$(cut -d' ' -f1 /s6overlay-base.tar.xz.sha256)  /s6overlay-base.tar.xz" > /SHA256SUMS \
+    && echo "$(cut -d' ' -f1 /s6overlay-bin.tar.xz.sha256)  /s6overlay-bin.tar.xz" >> /SHA256SUMS \
+    && echo "$(cut -d' ' -f1 /s6overlay-arch-symlinks.tar.xz.sha256)  /s6overlay-arch-symlinks.tar.xz" >> /SHA256SUMS \
+    && echo "$(cut -d' ' -f1 /s6overlay-noarch-symlinks.tar.xz.sha256)  /s6overlay-noarch-symlinks.tar.xz" >> /SHA256SUMS \
+    # Verify integrity of downloaded files
+    && sha256sum -c /SHA256SUMS
 
 
+# Builder stage
+FROM busybox AS builder
 
-# Third stage - Download s6-overlay platform-dependent hashes
-FROM alpine:3.21 AS downloader-s6-sha256-sums
-ARG TARGETPLATFORM
-ARG S6_OVERLAY_VERSION
-ARG S6_OVERLAY_RELEASE
-ARG S6_OVERLAY_PAK_EXT
-ARG S6_OVERLAY_BASE_HASH_URL="${S6_OVERLAY_RELEASE}/v${S6_OVERLAY_VERSION}/s6-overlay-noarch${S6_OVERLAY_PAK_EXT}.sha256"
-ARG S6_OVERLAY_BIN_HASH_URL="${S6_OVERLAY_RELEASE}/v${S6_OVERLAY_VERSION}/s6-overlay-${TARGETPLATFORM}${S6_OVERLAY_PAK_EXT}.sha256"
+COPY --from=downloader ["/s6overlay-base.tar.xz", "/s6overlay-bin.tar.xz", "/s6overlay-arch-symlinks.tar.xz", "/s6overlay-noarch-symlinks.tar.xz", "/tmp/s6/"]
 
 RUN set -eux \
-    && apk add --no-cache wget \
-    && wget -O /s6overlay-base.tar.xz.sha256 "${S6_OVERLAY_BASE_HASH_URL}" \
-    && wget -O /s6overlay-bin.tar.xz.sha256 "$(echo "${S6_OVERLAY_BIN_HASH_URL}" | sed 's/linux\///g' | sed 's/amd64/x86_64/g' | sed 's/arm64/aarch64/g' | sed 's/arm\/v7/armhf/g')" \
-    && echo "$(cat /s6overlay-base.tar.xz.sha256 | cut -d' ' -f1)  /s6overlay-base.tar.xz" > /SHA256SUMS \
-    && echo "$(cat /s6overlay-bin.tar.xz.sha256 | cut -d' ' -f1)  /s6overlay-bin.tar.xz" >> /SHA256SUMS \
-    && rm /s6overlay-base.tar.xz.sha256 \
-    && rm /s6overlay-bin.tar.xz.sha256
+    && mkdir -p /build \
+    && tar -Jxpf /tmp/s6/s6overlay-base.tar.xz -C /build \
+    && tar -Jxpf /tmp/s6/s6overlay-bin.tar.xz -C /build \
+    && tar -Jxpf /tmp/s6/s6overlay-arch-symlinks.tar.xz -C /build \
+    && tar -Jxpf /tmp/s6/s6overlay-noarch-symlinks.tar.xz -C /build
 
 
 
-# Fourth stage - Build rootfs from s6 parts
-FROM alpine:3.21 AS rootfs-builder
+# Rootfs
+FROM scratch AS rootfs
 
-COPY --from=downloader-s6-sha256-sums ["/SHA256SUMS", "/"]
-COPY --from=downloader-s6-base ["/s6overlay-base.tar.xz", "/s6overlay-base.tar.xz"]
-COPY --from=downloader-s6-bin  ["/s6overlay-bin.tar.xz", "/s6overlay-bin.tar.xz"]
-
-WORKDIR "/rootfs-build/"
-
-RUN set -eux \
-    && sha256sum -c /SHA256SUMS \
-    && apk add --no-cache tar xz \
-    && tar -Jxpf /s6overlay-base.tar.xz -C /rootfs-build \
-    && tar -Jxpf /s6overlay-bin.tar.xz -C /rootfs-build
+COPY --from=builder ["/build/", "/"]
 
 
-# Final stage
-FROM scratch AS s6-rootfs
+
+# Final image: minimal rootfs
+FROM scratch
 
 LABEL maintainer="Aleksandar Puharic <aleksandar@puharic.com>"
 
-COPY --from=rootfs-builder ["/rootfs-build/", "/"]
+COPY --from=rootfs ["/", "/"]
diff --git a/Dockerfile.legacy b/Dockerfile.legacy
index 5472c19..e240af3 100644
--- a/Dockerfile.legacy
+++ b/Dockerfile.legacy
@@ -1,5 +1,5 @@
 # First stage - Download s6-overlay and unpack it
-FROM alpine:3.21 AS downloader
+FROM busybox AS downloader
 
 ARG TARGETPLATFORM
 
@@ -7,15 +7,15 @@ ARG TARGETPLATFORM
 ARG S6_OVERLAY_VERSION="2.2.0.3"
 ARG S6_OVERLAY_RELEASE="https://github.com/just-containers/s6-overlay/releases/download/v${S6_OVERLAY_VERSION}/s6-overlay-${TARGETPLATFORM}.tar.gz"
 
-WORKDIR "/s6-overlay/"
-
-RUN apk add --no-cache wget tar gzip \
+RUN set -eux \
+    && mkdir -p /s6-overlay \
     && wget -O /tmp/s6overlay.tar.gz $(echo ${S6_OVERLAY_RELEASE} | sed 's/linux\///g' | sed 's/arm64/aarch64/g' | sed 's/arm\/v7/armhf/g') \
     && tar xzf /tmp/s6overlay.tar.gz -C /s6-overlay
 
 
+
 # Final stage
-FROM scratch AS s6-rootfs
+FROM scratch
 
 LABEL maintainer="Aleksandar Puharic <aleksandar@puharic.com>"