Fix Docker build for loong64

Use debian:stable-slim as base image for loong64 since Alpine
has no loong64 support.

Author: nekohasekai

.github/workflows/docker.yml

@@ -1,10 +1,10 @@
 name: Publish Docker Images
 
 on:
-  #push:
-  #  branches:
-  #    - main-next
-  #    - dev-next
+  push:
+    branches:
+      - main-next
+      - dev-next
   release:
     types:
       - published
@@ -160,17 +160,17 @@ jobs:
     strategy:
       fail-fast: true
       matrix:
-        platform:
-          - linux/amd64
-          - linux/arm/v6
-          - linux/arm/v7
-          - linux/arm64
-          - linux/386
-          - linux/mipsle
-          - linux/ppc64le
-          - linux/riscv64
-          - linux/s390x
-          - linux/loong64
+        include:
+          - { platform: "linux/amd64" }
+          - { platform: "linux/arm/v6" }
+          - { platform: "linux/arm/v7" }
+          - { platform: "linux/arm64" }
+          - { platform: "linux/386" }
+          - { platform: "linux/mipsle" }
+          - { platform: "linux/ppc64le" }
+          - { platform: "linux/riscv64" }
+          - { platform: "linux/s390x" }
+          - { platform: "linux/loong64", base_image: "debian:stable-slim" }
     steps:
       - name: Get commit to build
         id: ref
@@ -223,6 +223,8 @@ jobs:
           platforms: ${{ matrix.platform }}
           context: .
           file: Dockerfile.binary
+          build-args: |
+            BASE_IMAGE=${{ matrix.base_image || 'alpine' }}
           labels: ${{ steps.meta.outputs.labels }}
           outputs: type=image,name=${{ env.REGISTRY_IMAGE }},push-by-digest=true,name-canonical=true,push=true
       - name: Export digest
@@ -238,6 +240,7 @@ jobs:
           if-no-files-found: error
           retention-days: 1
   merge:
+    if: github.event_name != 'push'
     runs-on: ubuntu-latest
     needs:
       - build_docker

Dockerfile.binary

@@ -1,8 +1,14 @@
-FROM alpine
+ARG BASE_IMAGE=alpine
+FROM ${BASE_IMAGE}
 ARG TARGETARCH
 ARG TARGETVARIANT
 LABEL maintainer="nekohasekai <contact-git@sekai.icu>"
 RUN set -ex \
-    && apk add --no-cache --upgrade bash tzdata ca-certificates nftables
+    && if command -v apk > /dev/null; then \
+        apk add --no-cache --upgrade bash tzdata ca-certificates nftables; \
+    else \
+        apt-get update && apt-get install -y --no-install-recommends bash tzdata ca-certificates nftables \
+        && rm -rf /var/lib/apt/lists/*; \
+    fi
 COPY sing-box-${TARGETARCH}${TARGETVARIANT} /usr/local/bin/sing-box
 ENTRYPOINT ["sing-box"]