From 74b0dc2d6dd3b0701c8527bfa889206b592e614b Mon Sep 17 00:00:00 2001
From: ofthesun9 <olivier@ofthesun.net>
Date: Fri, 3 Apr 2020 15:39:11 +0200
Subject: [PATCH] Modify Dockerfile to allow docker cross build Provide
 Readme.armhf with short instructions

---
 Dockerfile   | 16 +++++++++-------
 Readme.armhf |  5 +++++
 2 files changed, 14 insertions(+), 7 deletions(-)
 create mode 100644 Readme.armhf

diff --git a/Dockerfile b/Dockerfile
index 5276b8e..41486b5 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,4 +1,6 @@
-FROM nginx:1.17.3
+ARG  DIST=nginx:1.17.3
+FROM $DIST
+ARG  ARCH=amd64
 
 WORKDIR /root
 
@@ -6,14 +8,14 @@ ENV S6_OVERLAY_VERSION v1.22.1.0
 ENV DOCKER_GEN_VERSION 0.7.4
 ENV ACME_TINY_VERSION 4.1.0
 
-ADD https://github.com/just-containers/s6-overlay/releases/download/$S6_OVERLAY_VERSION/s6-overlay-amd64.tar.gz /tmp/
-ADD https://github.com/jwilder/docker-gen/releases/download/$DOCKER_GEN_VERSION/docker-gen-linux-amd64-$DOCKER_GEN_VERSION.tar.gz /tmp/
+ADD https://github.com/just-containers/s6-overlay/releases/download/$S6_OVERLAY_VERSION/s6-overlay-$ARCH.tar.gz /tmp/
+ADD https://github.com/jwilder/docker-gen/releases/download/$DOCKER_GEN_VERSION/docker-gen-linux-$ARCH-$DOCKER_GEN_VERSION.tar.gz /tmp/
 ADD https://raw.githubusercontent.com/diafygi/acme-tiny/$ACME_TINY_VERSION/acme_tiny.py /bin/acme_tiny
 
-RUN tar xzf /tmp/s6-overlay-amd64.tar.gz -C / &&\
-    tar -C /bin -xzf /tmp/docker-gen-linux-amd64-$DOCKER_GEN_VERSION.tar.gz && \
-    rm /tmp/docker-gen-linux-amd64-$DOCKER_GEN_VERSION.tar.gz && \
-    rm /tmp/s6-overlay-amd64.tar.gz && \
+RUN tar xzf /tmp/s6-overlay-$ARCH.tar.gz -C / &&\
+    tar -C /bin -xzf /tmp/docker-gen-linux-${ARCH}-$DOCKER_GEN_VERSION.tar.gz && \
+    rm /tmp/docker-gen-linux-$ARCH-$DOCKER_GEN_VERSION.tar.gz && \
+    rm /tmp/s6-overlay-$ARCH.tar.gz && \
     rm /etc/nginx/conf.d/default.conf && \
     apt-get update && \
     apt-get install -y python ruby cron iproute2 apache2-utils && \
diff --git a/Readme.armhf b/Readme.armhf
new file mode 100644
index 0000000..3b9e602
--- /dev/null
+++ b/Readme.armhf
@@ -0,0 +1,5 @@
+#to build armhf image from amd64 machine:
+#Install qemu, see https://github.com/multiarch/qemu-user-static
+docker run --rm --privileged multiarch/qemu-user-static --reset -p yes
+#Pass relevant args to the docker build cmd
+docker build  --build-arg DIST=arm32v7/nginx:1.17.3 --build-arg ARCH=armhf -t https-portal:armhf-master .