From 9b28fbc24ddad49b29146fe48fad78cac02838e4 Mon Sep 17 00:00:00 2001
From: jebabin <github.com@jeb.be>
Date: Mon, 18 Sep 2023 14:30:32 +0200
Subject: [PATCH] chore: update Dockerfile.dev-self-contained to allow better
 build cache (#1755)

---
 dockerfiles/Dockerfile.dev-self-contained | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/dockerfiles/Dockerfile.dev-self-contained b/dockerfiles/Dockerfile.dev-self-contained
index 7126459..1a39c26 100644
--- a/dockerfiles/Dockerfile.dev-self-contained
+++ b/dockerfiles/Dockerfile.dev-self-contained
@@ -7,6 +7,13 @@ FROM golang:alpine as builder
 # use version (for example "v0.3.3") or "main"
 ARG WATCHTOWER_VERSION=main
 
+# Pre download required modules to avoid redownloading at each build thanks to docker layer caching.
+# Copying go.mod and go.sum ensure to invalid the layer/build cache if there is a change in module requirement
+WORKDIR /watchtower
+COPY go.mod .
+COPY go.sum .
+RUN go mod download
+
 RUN apk add --no-cache \
     alpine-sdk \
     ca-certificates \