From 2cfe043f5eaf9e8ac79dcb1e640649f9fba2d715 Mon Sep 17 00:00:00 2001
From: "Brian C. Lane" <bcl@redhat.com>
Date: Fri, 28 Mar 2025 14:35:46 -0700
Subject: [PATCH] main: Add a --version flag to show the build version

This embeds the version at build time and displays it when passed the
--version flag.
---
 Makefile                  | 2 +-
 cmd/image-builder/main.go | 6 ++++--
 image-builder.spec        | 1 +
 3 files changed, 6 insertions(+), 3 deletions(-)

diff --git a/Makefile b/Makefile
index ca48e59..404dc3f 100644
--- a/Makefile
+++ b/Makefile
@@ -98,7 +98,7 @@ $(BUILDDIR)/%/:
 
 .PHONY: build
 build: $(BUILDDIR)/bin/  ## build the binary from source
-	go build -o $<image-builder ./cmd/image-builder/
+	go build -ldflags="-X main.BuildVersion=${VERSION}" -o $<image-builder ./cmd/image-builder/
 
 .PHONY: clean
 clean:  ## Remove all built binaries
diff --git a/cmd/image-builder/main.go b/cmd/image-builder/main.go
index c1ea44a..0757da4 100644
--- a/cmd/image-builder/main.go
+++ b/cmd/image-builder/main.go
@@ -25,8 +25,9 @@ import (
 )
 
 var (
-	osStdout io.Writer = os.Stdout
-	osStderr io.Writer = os.Stderr
+	osStdout     io.Writer = os.Stdout
+	osStderr     io.Writer = os.Stderr
+	BuildVersion           = "DEVEL"
 )
 
 // basenameFor returns the basename for directory and filenames
@@ -378,6 +379,7 @@ image-type and blueprint.
 Image-builder builds operating system images for a range of predefined
 operating systems like Fedora, CentOS and RHEL with easy customizations support.`,
 		SilenceErrors: true,
+		Version:       BuildVersion,
 	}
 	rootCmd.PersistentFlags().String("data-dir", "", `Override the default data directory for e.g. custom repositories/*.json data`)
 	rootCmd.PersistentFlags().StringArray("extra-repo", nil, `Add an extra repository during build (will *not* be gpg checked and not be part of the final image)`)
diff --git a/image-builder.spec b/image-builder.spec
index be683f2..219bdcc 100644
--- a/image-builder.spec
+++ b/image-builder.spec
@@ -85,6 +85,7 @@ export GOFLAGS+=" -mod=vendor"
 GOTAGS="exclude_graphdriver_btrfs"
 %endif
 
+export LDFLAGS="${LDFLAGS} -X 'main.BuildVersion=%{version}'"
 %gobuild ${GOTAGS:+-tags=$GOTAGS} -o %{gobuilddir}/bin/image-builder %{goipath}/cmd/image-builder
 
 %install