feat: initial docker

Dockerfile

@@ -0,0 +1,18 @@
+FROM plugins/base:amd64
+
+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 1.2.5
+RUN wget -q https://releases.hashicorp.com/packer/${PACKER_VERSION}/packer_${PACKER_VERSION}_linux_amd64.zip -O packer.zip && \
+  unzip packer.zip -d /bin && \
+  rm -f packer.zip
+
+ADD release/linux/amd64/drone-packer /bin/
+ENTRYPOINT ["/bin/drone-packer"]