chore(makefile): enhance reproducible build (#1181)

Signed-off-by: Batuhan Apaydın <[email protected]> Co-authored-by: Morten Linderud <[email protected]> Signed-off-by: Batuhan Apaydın <[email protected]> Co-authored-by: Morten Linderud <[email protected]>
aws · Jan 19, 2022 · dc72a87 · dc72a87
1 parent 43ede27
commit dc72a87
Showing 1 changed file with 9 additions and 1 deletion.
diff --git a/Makefile b/Makefile
@@ -2,8 +2,16 @@ RELEASE_REPO ?= public.ecr.aws/karpenter
 RELEASE_VERSION ?= $(shell git describe --tags --always)
 RELEASE_PLATFORM ?= --platform=linux/amd64,linux/arm64
 
+# https://reproducible-builds.org/docs/source-date-epoch/
+DATE_FMT = +%Y-%m-%dT%H:%M:%SZ
+ifdef SOURCE_DATE_EPOCH
+    BUILD_DATE ?= $(shell date -u -d "@$(SOURCE_DATE_EPOCH)" "$(DATE_FMT)" 2>/dev/null || date -u -r "$(SOURCE_DATE_EPOCH)" "$(DATE_FMT)" 2>/dev/null || date -u "$(DATE_FMT)")
+else
+    BUILD_DATE ?= $(shell date "$(DATE_FMT)")
+endif
+
 ## Inject these annotations to cosign signing
-COSIGN_FLAGS ?= -a GIT_HASH=$(shell git rev-parse HEAD) -a GIT_VERSION=${RELEASE_VERSION} -a BUILD_DATE=$(shell date +'%Y-%m-%dT%H:%M:%SZ')
+COSIGN_FLAGS ?= -a GIT_HASH=$(shell git rev-parse HEAD) -a GIT_VERSION=${RELEASE_VERSION} -a BUILD_DATE=$BUILD_DATE
 
 ## Inject the app version into project.Version
 LDFLAGS ?= "-ldflags=-X=github.com/aws/karpenter/pkg/utils/project.Version=$(RELEASE_VERSION)"