From ad164ac7f2055ac9061cc6a06eafed68d9365d4d Mon Sep 17 00:00:00 2001
From: Roberto Alsina <roberto.alsina@gmail.com>
Date: Thu, 1 Jun 2023 19:32:12 -0300
Subject: [PATCH] Make image smaller, use the correct platform

---
 template/crystal/Dockerfile | 28 +++++++++++++---------------
 1 file changed, 13 insertions(+), 15 deletions(-)

diff --git a/template/crystal/Dockerfile b/template/crystal/Dockerfile
index d3ffda0..6d41aaa 100644
--- a/template/crystal/Dockerfile
+++ b/template/crystal/Dockerfile
@@ -1,30 +1,28 @@
-FROM crystallang/crystal:1.8.0 as builder
+FROM --platform=${TARGETPLATFORM:-linux/amd64} ghcr.io/openfaas/of-watchdog:0.9.10 as watchdog
+FROM --platform=${TARGETPLATFORM:-linux/amd64} alpine as build
 
-RUN apt update \
-    && apt install -y curl \
-    && echo "Pulling watchdog binary from Github." \
-    && curl -sSL https://github.com/openfaas/faas/releases/download/0.9.6/fwatchdog > /usr/bin/fwatchdog \
-    && chmod +x /usr/bin/fwatchdog
 
+RUN apk add crystal shards
 WORKDIR /home/app
 COPY . .
 
 COPY function/shard.yml shard.yml
 RUN shards install
-RUN crystal build main.cr -o handler --release
-
-FROM crystallang/crystal:1.8.0
-RUN apt install ca-certificates
+RUN crystal build main.cr -o handler --release --static
+RUN strip handler
 
+FROM --platform=${TARGETPLATFORM:-linux/amd64} alpine as ship
 # Add non root user
-RUN adduser app
-RUN mkdir -p /home/app
+# Add non root user
+RUN addgroup -S app && adduser app -S -G app
+RUN chown app /home/app
 
 WORKDIR /home/app
 
-COPY --from=builder /usr/bin/fwatchdog   .
-COPY --from=builder /home/app/function/  .
-COPY --from=builder /home/app/handler    .
+COPY --from=build /home/app/function/  .
+COPY --from=build /home/app/handler    .
+COPY --from=watchdog /fwatchdog /home/app/fwatchdog
+RUN chmod +x /home/app/fwatchdog
 
 RUN chown -R app /home/app