feat: support i386 docker image.

.drone.yml

@@ -93,6 +93,19 @@ pipeline:
       event: [ push, tag ]
       local: false
 
+  publish_linux_i386:
+    image: plugins/docker:17.05
+    pull: true
+    secrets: [ docker_username, docker_password ]
+    group: release
+    repo: ${DRONE_REPO}
+    auto_tag: true
+    auto_tag_suffix: i386
+    dockerfile: Dockerfile.i386
+    when:
+      event: [ push, tag ]
+      local: false
+
   discord:
     image: appleboy/drone-discord
     pull: true

Dockerfile.i386

@@ -0,0 +1,19 @@
+FROM plugins/base:multiarch
+
+LABEL maintainer="Bo-Yi Wu <appleboy.tw@gmail.com>" \
+  org.label-schema.name="Drone Packer" \
+  org.label-schema.vendor="Bo-Yi Wu" \
+  org.label-schema.schema-version="1.0"
+
+RUN apk add --no-cache ca-certificates \
+  wget && \
+  rm -rf /var/cache/apk/*
+
+ENV PACKER_VERSION 1.3.1
+ENV PACKER_ARCH 386
+RUN wget -q https://releases.hashicorp.com/packer/${PACKER_VERSION}/packer_${PACKER_VERSION}_linux_${PACKER_ARCH}.zip -O packer.zip && \
+  unzip packer.zip -d /bin && \
+  rm -f packer.zip
+
+ADD release/linux/i${PACKER_ARCH}/drone-packer /bin/
+ENTRYPOINT ["/bin/drone-packer"]