Install mount binaries in Docker images (#47)

Signed-off-by: Tamal Saha <tamal@appscode.com>

Dockerfile.dbg

@@ -5,7 +5,7 @@ ENV DEBCONF_NONINTERACTIVE_SEEN true
 
 RUN set -x \
   && apt-get update \
-  && apt-get install -y --no-install-recommends ca-certificates tzdata locales \
+  && apt-get install -y --no-install-recommends ca-certificates tzdata locales e2fsprogs mount \
   && rm -rf /var/lib/apt/lists/* /usr/share/doc /usr/share/man /tmp/* \
   && localedef -i en_US -c -f UTF-8 -A /usr/share/locale/locale.alias en_US.UTF-8 \
   && echo 'Etc/UTC' > /etc/timezone && dpkg-reconfigure tzdata

Dockerfile.in

@@ -1,12 +1,8 @@
-FROM alpine as certs
-RUN apk add --update ca-certificates
-
 FROM {ARG_FROM}
 
-COPY --from=certs /etc/ssl/certs /etc/ssl/certs
-ADD bin/{ARG_OS}_{ARG_ARCH}/{ARG_BIN} /{ARG_BIN}
+RUN set -x \
+  && apk add --update --no-cache ca-certificates tzdata e2fsprogs findmnt
 
-# This would be nicer as `nobody:nobody` but distroless has no such entries.
-USER 65535:65535
+ADD bin/{ARG_OS}_{ARG_ARCH}/{ARG_BIN} /{ARG_BIN}
 
 ENTRYPOINT ["/{ARG_BIN}"]

Makefile

@@ -40,7 +40,7 @@ BIN_PLATFORMS    := $(DOCKER_PLATFORMS)
 OS   := $(if $(GOOS),$(GOOS),$(shell go env GOOS))
 ARCH := $(if $(GOARCH),$(GOARCH),$(shell go env GOARCH))
 
-BASEIMAGE_PROD   ?= busybox
+BASEIMAGE_PROD   ?= alpine:3.9
 BASEIMAGE_DBG    ?= debian:stretch
 
 IMAGE            := $(REGISTRY)/$(BIN)