Include git-version in gitaly_build_info metrics

3 files changed, 36 insertions, 2 deletions

diff --git a/CHANGELOG.md b/CHANGELOG.md
index b498e63cc..98ca11a6f 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,6 +2,8 @@
 
 UNRELEASED
 
+- Add `git version` to `gitaly_build_info` metrics
+  https://gitlab.com/gitlab-org/gitaly/merge_requests/400
 - Use relative paths for git object dir attributes
   https://gitlab.com/gitlab-org/gitaly/merge_requests/393
 
diff --git a/cmd/gitaly/main.go b/cmd/gitaly/main.go
index 1ba31c693..749a53253 100644
--- a/cmd/gitaly/main.go
+++ b/cmd/gitaly/main.go
@@ -13,6 +13,7 @@ import (
 
 	"gitlab.com/gitlab-org/gitaly/internal/config"
 	"gitlab.com/gitlab-org/gitaly/internal/connectioncounter"
+	"gitlab.com/gitlab-org/gitaly/internal/git"
 	"gitlab.com/gitlab-org/gitaly/internal/linguist"
 	"gitlab.com/gitlab-org/gitaly/internal/rubyserver"
 	"gitlab.com/gitlab-org/gitaly/internal/server"
@@ -47,12 +48,18 @@ func loadConfig(configPath string) error {
 // registerServerVersionPromGauge registers a label with the current server version
 // making it easy to see what versions of Gitaly are running across a cluster
 func registerServerVersionPromGauge() {
+	gitVersion, err := git.Version()
+	if err != nil {
+		fmt.Printf("git version: %v\n", err)
+		os.Exit(1)
+	}
 	gitlabBuildInfoGauge := prometheus.NewGauge(prometheus.GaugeOpts{
 		Name: "gitlab_build_info",
 		Help: "Current build info for this GitLab Service",
 		ConstLabels: prometheus.Labels{
-			"version": version.GetVersion(),
-			"built":   version.GetBuildTime(),
+			"version":     version.GetVersion(),
+			"built":       version.GetBuildTime(),
+			"git_version": gitVersion,
 		},
 	})
 
diff --git a/internal/git/helper.go b/internal/git/helper.go
index dc755f437..00966d4d0 100644
--- a/internal/git/helper.go
+++ b/internal/git/helper.go
@@ -2,11 +2,15 @@ package git
 
 import (
 	"bytes"
+	"context"
 	"fmt"
+	"os/exec"
+	"strings"
 	"time"
 
 	"github.com/golang/protobuf/ptypes/timestamp"
 	pb "gitlab.com/gitlab-org/gitaly-proto/go"
+	"gitlab.com/gitlab-org/gitaly/internal/command"
 )
 
 // FallbackTimeValue is the value returned by `SafeTimeParse` in case it
@@ -64,3 +68,24 @@ func NewCommit(id, subject, body, authorName, authorEmail, authorDate,
 		ParentIds: parentIds,
 	}, nil
 }
+
+// Version returns the used git version.
+func Version() (string, error) {
+	var buf bytes.Buffer
+	cmd, err := command.New(context.Background(), exec.Command(command.GitPath(), "version"), nil, &buf, nil)
+	if err != nil {
+		return "", err
+	}
+
+	if err = cmd.Wait(); err != nil {
+		return "", err
+	}
+
+	out := strings.Trim(buf.String(), " \n")
+	ver := strings.SplitN(out, " ", 3)
+	if len(ver) != 3 {
+		return "", fmt.Errorf("invalid version format: %q", buf.String())
+	}
+
+	return ver[2], nil
+}