Dockerfile for Alpine 3.8.

FROM alpine:3.8 as scratch

ENV GOSU_VERSION 1.10

RUN set -ex; \

	\

	apk add --no-cache --virtual .gosu-deps \

		dpkg \

		gnupg \

		openssl \

	; \

	\

	dpkgArch="$(dpkg --print-architecture | awk -F- '{ print $NF }')"; \

	wget -O /usr/local/bin/gosu "https://github.com/tianon/gosu/releases/download/$GOSU_VERSION/gosu-$dpkgArch"; \

	wget -O /usr/local/bin/gosu.asc "https://github.com/tianon/gosu/releases/download/$GOSU_VERSION/gosu-$dpkgArch.asc"; \

	\

# verify the signature

	export GNUPGHOME="$(mktemp -d)"; \

	gpg --keyserver ha.pool.sks-keyservers.net --recv-keys B42F6819007F00F88E364FD4036A9C25BF357DD4; \

	gpg --batch --verify /usr/local/bin/gosu.asc /usr/local/bin/gosu; \

	\

	chmod +x /usr/local/bin/gosu; \

# verify that the binary works

	gosu nobody true;

FROM alpine:3.8

COPY --from=scratch /usr/local/bin/gosu /usr/local/bin/