From aa15d1e9c1a01b137dd75b3a6b752ff328815e6e Mon Sep 17 00:00:00 2001
From: Tom Wieczorek <twieczorek@mirantis.com>
Date: Mon, 2 Oct 2023 11:51:46 +0200
Subject: [PATCH] Forward SOURCE_DATE_EPOCH to embedded k8s binaries

Make it possible for embedded binaries to pick up the SOURCE_DATE_EPOCH
with which k0s is built. If supported, the embedded binaries will
display the same build date as the k0s binary.

Currently, only Kubernetes binaries will get the timestamp. It still
needs to be checked what other binaries embed the build date.

Also remove some Go build flags that get added by default in the
Kubernetes build.

Signed-off-by: Tom Wieczorek <twieczorek@mirantis.com>
---
 Makefile                            | 12 +++++-------
 embedded-bins/Makefile              |  5 +++++
 embedded-bins/Makefile.variables    |  2 +-
 embedded-bins/kubernetes/Dockerfile |  5 ++++-
 4 files changed, 15 insertions(+), 9 deletions(-)

diff --git a/Makefile b/Makefile
index 32e7f7f29c8c..ec3f418b5a60 100644
--- a/Makefile
+++ b/Makefile
@@ -41,13 +41,9 @@ endif
 
 # https://reproducible-builds.org/docs/source-date-epoch/#makefile
 # https://reproducible-builds.org/docs/source-date-epoch/#git
-# https://stackoverflow.com/a/15103333
+SOURCE_DATE_EPOCH ?= $(shell git log -1 --pretty=%ct || date -u +%s)
 BUILD_DATE_FMT = %Y-%m-%dT%H:%M:%SZ
-ifdef SOURCE_DATE_EPOCH
-	BUILD_DATE ?= $(shell date -u -d "@$(SOURCE_DATE_EPOCH)" "+$(BUILD_DATE_FMT)" 2>/dev/null || date -u -r "$(SOURCE_DATE_EPOCH)" "+$(BUILD_DATE_FMT)" 2>/dev/null || date -u "+$(BUILD_DATE_FMT)")
-else
-	BUILD_DATE ?= $(shell TZ=UTC git log -1 --pretty=%cd --date='format-local:$(BUILD_DATE_FMT)' || date -u +$(BUILD_DATE_FMT))
-endif
+BUILD_DATE ?= $(shell date -u -d "@$(SOURCE_DATE_EPOCH)" "+$(BUILD_DATE_FMT)" 2>/dev/null || date -u -r "$(SOURCE_DATE_EPOCH)" "+$(BUILD_DATE_FMT)" 2>/dev/null || date -u "+$(BUILD_DATE_FMT)")
 
 LD_FLAGS += -X github.com/k0sproject/k0s/pkg/build.Version=$(VERSION)
 LD_FLAGS += -X github.com/k0sproject/k0s/pkg/build.RuncVersion=$(runc_version)
@@ -197,7 +193,9 @@ k0s.exe k0s: $(GO_SRCS) $(codegen_targets) go.sum
 		&& mv $@.tmp $@
 
 .bins.windows.stamp .bins.linux.stamp: embedded-bins/Makefile.variables
-	$(MAKE) -C embedded-bins buildmode=$(EMBEDDED_BINS_BUILDMODE) TARGET_OS=$(patsubst .bins.%.stamp,%,$@)
+	$(MAKE) -C embedded-bins \
+	  TARGET_OS=$(patsubst .bins.%.stamp,%,$@) \
+	  SOURCE_DATE_EPOCH=$(SOURCE_DATE_EPOCH)
 	touch $@
 
 .PHONY: codegen
diff --git a/embedded-bins/Makefile b/embedded-bins/Makefile
index 5babe263845d..8b833a6d8087 100644
--- a/embedded-bins/Makefile
+++ b/embedded-bins/Makefile
@@ -6,6 +6,10 @@ export GOOS
 TARGET_OS ?= linux
 export TARGET_OS
 
+# https://reproducible-builds.org/docs/source-date-epoch/#makefile
+# https://reproducible-builds.org/docs/source-date-epoch/#git
+SOURCE_DATE_EPOCH ?= $(shell git log -1 --pretty=%ct || date -u +%s)
+
 bindir = staging/${TARGET_OS}/bin
 posix_bins = runc kubelet containerd containerd-shim containerd-shim-runc-v1 containerd-shim-runc-v2 kube-apiserver kube-scheduler kube-controller-manager etcd kine konnectivity-server xtables-legacy-multi xtables-nft-multi
 windows_bins = kubelet.exe kube-proxy.exe containerd.exe containerd-shim-runhcs-v1.exe
@@ -79,6 +83,7 @@ build_docker_image = \
 	  --build-arg CONTAINERD_BINS="$(containerd_bins)" \
 	  --build-arg KUBERNETES_BINS="$(kubernetes_bins)" \
 	  --build-arg VERSION=$($(patsubst %/Dockerfile,%,$<)_version) \
+	  --build-arg SOURCE_DATE_EPOCH=$(SOURCE_DATE_EPOCH) \
 	  --build-arg BUILDIMAGE=$($(patsubst %/Dockerfile,%,$<)_buildimage) \
 	  --build-arg BUILD_GO_TAGS=$($(patsubst %/Dockerfile,%,$<)_build_go_tags) \
 	  --build-arg BUILD_GO_CGO_ENABLED=$($(patsubst %/Dockerfile,%,$<)_build_go_cgo_enabled) \
diff --git a/embedded-bins/Makefile.variables b/embedded-bins/Makefile.variables
index a8350b9d3f9c..5e05d5a935cf 100644
--- a/embedded-bins/Makefile.variables
+++ b/embedded-bins/Makefile.variables
@@ -30,7 +30,7 @@ kubernetes_build_go_tags = "providerless"
 #kubernetes_build_go_cgo_cflags =
 kubernetes_build_go_flags = "-v"
 #kubernetes_build_go_ldflags =
-kubernetes_build_go_ldflags_extra = "-w -s -extldflags=-static"
+kubernetes_build_go_ldflags_extra = "-extldflags=-static"
 
 kine_version = 0.10.3
 kine_buildimage = $(golang_buildimage)
diff --git a/embedded-bins/kubernetes/Dockerfile b/embedded-bins/kubernetes/Dockerfile
index a453ad7c3b9c..99b023fd5b07 100644
--- a/embedded-bins/kubernetes/Dockerfile
+++ b/embedded-bins/kubernetes/Dockerfile
@@ -9,6 +9,7 @@ RUN git -c advice.detachedHead=false clone -b v$VERSION --depth=1 https://github
 WORKDIR /go/src/github.com/kubernetes/kubernetes
 
 ARG TARGET_OS \
+  SOURCE_DATE_EPOCH \
   BUILD_GO_TAGS \
   BUILD_GO_CGO_ENABLED \
   BUILD_GO_FLAGS \
@@ -17,7 +18,7 @@ ARG TARGET_OS \
   KUBERNETES_BINS
 
 RUN \
-  set -e; \
+  set -ex; \
   export GOPATH=/go; \
   if [ "${TARGET_OS}" = windows ]; then \
     commands="${KUBERNETES_BINS}"; \
@@ -34,7 +35,9 @@ RUN \
     export KUBE_STATIC_OVERRIDES=$commands; \
   fi; \
   mkdir /out; \
+  export SOURCE_DATE_EPOCH=$SOURCE_DATE_EPOCH; \
   export FORCE_HOST_GO=y; \
+  export KUBE_VERBOSE=9; \
   export KUBE_GIT_VERSION="v$VERSION+k0s"; \
   for cmd in $commands; do \
     make GOFLAGS="${BUILD_GO_FLAGS} -tags=${BUILD_GO_TAGS}" GOLDFLAGS="${BUILD_GO_LDFLAGS_EXTRA}" WHAT=cmd/$cmd; \