PT-2164 version flag for pt-k8s-debug-collector (#576)

* PT-2164 - pt-k8s-debug-collector does not have version flag

Added flag
Updated README

* PT-2164 - pt-k8s-debug-collector does not have version flag

Added test case

* PT-2164 version flag for pt-k8s-debug-collector

go fmt for src/go/pt-k8s-debug-collector/main.go

* PT-2164 version flag for pt-k8s-debug-collector

Updated docs/pt-k8s-debug-collector.rst

docs/pt-k8s-debug-collector.rst

@@ -122,7 +122,7 @@ Usage
 
 ``pt-k8s-debug-collector <flags>``
 
-Supported Flags:
+Supported Flags
 ================
 
 ``--resource`` 
@@ -157,12 +157,18 @@ Path to kubeconfig. Default configuration be used if none specified
 
 Port to use when collecting database-specific summaries. By default, 3306 will be used for PXC and MySQL, 27017 for MongoDB, and 5432 for PostgreSQL
 
+``--version``
+
+Print version info
+
 Requirements
 ============
 
 - Installed, configured, and available in PATH ``kubectl``
 - Installed, configured, and available in PATH ``pt-mysql-summary`` for PXC and MySQL
+- Installed, configured, and available in PATH ``mysql`` for PXC and MySQL
 - Installed, configured, and available in PATH ``pt-mongodb-summary`` for MongoDB
+- Installed, configured, and available in PATH ``psql`` for PostgreSQL
 
 Known Issues
 ============

src/go/pt-k8s-debug-collector/README.rst

@@ -122,7 +122,7 @@ Usage
 
 ``pt-k8s-debug-collector <flags>``
 
-Supported Flags:
+Supported Flags
 ================
 
 ``--resource`` 
@@ -157,12 +157,18 @@ Path to kubeconfig. Default configuration be used if none specified
 
 Port to use when collecting database-specific summaries. By default, 3306 will be used for PXC and MySQL, 27017 for MongoDB, and 5432 for PostgreSQL
 
+``--version``
+
+Print version info
+
 Requirements
 ============
 
 - Installed, configured, and available in PATH ``kubectl``
 - Installed, configured, and available in PATH ``pt-mysql-summary`` for PXC and MySQL
+- Installed, configured, and available in PATH ``mysql`` for PXC and MySQL
 - Installed, configured, and available in PATH ``pt-mongodb-summary`` for MongoDB
+- Installed, configured, and available in PATH ``psql`` for PostgreSQL
 
 Known Issues
 ============

src/go/pt-k8s-debug-collector/main.go

@@ -2,26 +2,50 @@ package main
 
 import (
 	"flag"
+	"fmt"
 	"log"
 	"os"
 
 	"github.com/percona/percona-toolkit/src/go/pt-k8s-debug-collector/dumper"
 )
 
+const (
+	TOOLNAME = "pt-k8s-debug-collector"
+)
+
+// We do not set anything here, these variables are defined by the Makefile
+var (
+	Build     string
+	GoVersion string
+	Version   string
+	Commit    string
+)
+
 func main() {
 	namespace := ""
 	resource := ""
 	clusterName := ""
 	kubeconfig := ""
 	forwardport := ""
+	version := false
 
 	flag.StringVar(&namespace, "namespace", "", "Namespace for collecting data. If empty data will be collected from all namespaces")
 	flag.StringVar(&resource, "resource", "none", "Collect data, specific to the resource. Supported values: pxc, psmdb, pg, ps, none")
 	flag.StringVar(&clusterName, "cluster", "", "Cluster name")
 	flag.StringVar(&kubeconfig, "kubeconfig", "", "Path to kubeconfig")
 	flag.StringVar(&forwardport, "forwardport", "", "Port to use for  port forwarding")
+	flag.BoolVar(&version, "version", false, "Print version")
 	flag.Parse()
 
+	if version {
+		fmt.Println(TOOLNAME)
+		fmt.Printf("Version %s\n", Version)
+		fmt.Printf("Build: %s using %s\n", Build, GoVersion)
+		fmt.Printf("Commit: %s\n", Commit)
+
+		return
+	}
+
 	if len(clusterName) > 0 {
 		resource += "/" + clusterName
 	}

src/go/pt-k8s-debug-collector/main_test.go

@@ -7,6 +7,7 @@ import (
 	"path"
 	"strings"
 	"testing"
+	"regexp"
 
 	"golang.org/x/exp/slices"
 )
@@ -22,7 +23,7 @@ This test requires:
 
 You can additionally set option FORWARDPORT if you want to use custom port when testing summaries.
 
-pt-mysql-summary and pt-mongodb-summary must be in the PATH.
+pt-mysql-summary, mysql, psql, and pt-mongodb-summary must be in the PATH.
 
 Since running pt-k8s-debug-collector may take long time run go test with increase timeout:
 go test -timeout 6000s
@@ -158,3 +159,18 @@ func TestResourceOption(t *testing.T) {
 		}
 	}
 }
+
+/*
+Option --version
+*/
+func TestVersionOption(t *testing.T) {
+	out, err := exec.Command("../../../bin/pt-k8s-debug-collector", "--version").Output()
+	if err != nil {
+		t.Errorf("error executing pt-k8s-debug-collector --version: %s", err.Error())
+	}
+	// We are using MustCompile here, because hard-coded RE should not fail
+	re := regexp.MustCompile(TOOLNAME + `\n.*Version \d+\.\d+\.\d+\n`)
+	if !re.Match(out) {
+		t.Errorf("pt-k8s-debug-collector --version returns wrong result:\n%s", out)
+	}
+}