From c2724f88a6aadbfeb1f41e89fa66c243243e2471 Mon Sep 17 00:00:00 2001
From: Alexander Staubo <alex@purefiction.net>
Date: Mon, 10 Aug 2020 13:12:31 -0400
Subject: [PATCH] Add --version flag.

---
 gen_version.sh | 19 +++++++++++++++++++
 main.go        |  9 ++++++++-
 version.go     |  7 +++++++
 3 files changed, 34 insertions(+), 1 deletion(-)
 create mode 100755 gen_version.sh
 create mode 100644 version.go

diff --git a/gen_version.sh b/gen_version.sh
new file mode 100755
index 0000000..333c95f
--- /dev/null
+++ b/gen_version.sh
@@ -0,0 +1,19 @@
+#!/bin/sh
+
+v=$(git tag --contains HEAD)
+if [ "$v" = "" ]; then
+  echo "Cannot determine tag." >&2
+  exit 1
+fi
+
+v=$(echo "$v" | sed -Ee 's#^v(.*)#\1#')
+
+cat <<END >version.go
+// Code generated by gen_version.sh, DO NOT EDIT.
+
+package main
+
+//go:generate sh -c ./gen_version.sh
+
+const version = "$v"
+END
diff --git a/main.go b/main.go
index afd961a..1d67ee5 100644
--- a/main.go
+++ b/main.go
@@ -9,7 +9,7 @@ import (
 
 	"github.com/fatih/color"
 	"github.com/spf13/pflag"
-	"k8s.io/api/core/v1"
+	v1 "k8s.io/api/core/v1"
 	"k8s.io/apimachinery/pkg/labels"
 	"k8s.io/client-go/kubernetes"
 	_ "k8s.io/client-go/plugin/pkg/client/auth/gcp"
@@ -29,6 +29,7 @@ func main() {
 		raw                   bool
 		tmplString            string
 		sinceStart            bool
+		showVersion           bool
 		includePatterns       []*regexp.Regexp
 		excludePatternStrings []string
 	)
@@ -55,12 +56,18 @@ func main() {
 	flags.BoolVarP(&quiet, "quiet", "q", false, "Don't print events about new/deleted pods")
 	flags.BoolVarP(&sinceStart, "since-start", "s", false,
 		"Start reading log from the beginning of the container's lifetime.")
+	flags.BoolVarP(&showVersion, "version", "", false, "Show version.")
 
 	if err := flags.Parse(os.Args[1:]); err != nil {
 		fail(err.Error())
 		os.Exit(1)
 	}
 
+	if showVersion {
+		fmt.Printf("ktail %s\n", version)
+		os.Exit(0)
+	}
+
 	var excludePatterns []*regexp.Regexp
 	for _, p := range excludePatternStrings {
 		r, err := regexp.Compile(p)
diff --git a/version.go b/version.go
new file mode 100644
index 0000000..ca7e1d4
--- /dev/null
+++ b/version.go
@@ -0,0 +1,7 @@
+// Code generated by gen_version.sh, DO NOT EDIT.
+
+package main
+
+//go:generate sh -c ./gen_version.sh
+
+const version = "1.0.0"