From 2895e12476368f9b494a37191cf362a88632c383 Mon Sep 17 00:00:00 2001
From: "Dustin C. Hatch" <dustin@hatch.name>
Date: Thu, 18 Jan 2024 07:45:35 -0600
Subject: [PATCH] Build a static executable, from scratch container

This reduces the size of the container image from 150 MB to 10 MB.
---
 Containerfile | 13 +++++++++----
 1 file changed, 9 insertions(+), 4 deletions(-)

diff --git a/Containerfile b/Containerfile
index f627193..76ae3a9 100644
--- a/Containerfile
+++ b/Containerfile
@@ -1,12 +1,17 @@
-FROM docker.io/library/golang:1.21 AS build
+FROM docker.io/library/golang:1.21-alpine AS build
+
+RUN --mount=type=cache,target=/var/cache \
+    apk add \
+        git \
+    && :
 
 RUN go install github.com/lucab/local_exporter@latest
 
 
-FROM registry.fedoraproject.org/fedora-minimal:38
+FROM scratch
 
-COPY --from=build /go/bin/local_exporter /usr/local/bin/local_exporter
+COPY --from=build /go/bin/local_exporter /local_exporter
 
-ENTRYPOINT ["local_exporter"]
+ENTRYPOINT ["/local_exporter"]
 
 USER 252:252