Read Go build info from the binary (#2319)

Problem: We're injecting information about the environment at build time. This could be unreliable and doesn't need to be done since `go` has all this info at build time already.

Solution: Get the info directly from the build.

Author: lucacome

.goreleaser.yml

@@ -18,8 +18,6 @@ builds:
     ldflags:
       - -s -w
       - -X main.version={{.Version}}
-      - -X main.commit={{.Commit}}
-      - -X main.date={{.Date}}
       - -X main.telemetryReportPeriod=24h
       - -X main.telemetryEndpoint={{.Env.TELEMETRY_ENDPOINT}}
       - -X main.telemetryEndpointInsecure={{.Env.TELEMETRY_ENDPOINT_INSECURE}}

Makefile

@@ -1,7 +1,5 @@
 # variables that should not be overridden by the user
 VERSION = edge
-GIT_COMMIT = $(shell git rev-parse HEAD || echo "unknown")
-DATE = $(shell date -u +"%Y-%m-%dT%H:%M:%SZ")
 SELF_DIR := $(dir $(lastword $(MAKEFILE_LIST)))
 MANIFEST_DIR = $(CURDIR)/deploy/manifests
 CHART_DIR = $(SELF_DIR)charts/nginx-gateway-fabric
@@ -22,7 +20,7 @@ ENABLE_EXPERIMENTAL ?= false
 NODE_VERSION = $(shell cat .nvmrc)
 
 # go build flags - should not be overridden by the user
-GO_LINKER_FlAGS_VARS = -X main.version=${VERSION} -X main.commit=${GIT_COMMIT} -X main.date=${DATE} -X main.telemetryReportPeriod=${TELEMETRY_REPORT_PERIOD} -X main.telemetryEndpoint=${TELEMETRY_ENDPOINT} -X main.telemetryEndpointInsecure=${TELEMETRY_ENDPOINT_INSECURE}
+GO_LINKER_FlAGS_VARS = -X main.version=${VERSION} -X main.telemetryReportPeriod=${TELEMETRY_REPORT_PERIOD} -X main.telemetryEndpoint=${TELEMETRY_ENDPOINT} -X main.telemetryEndpointInsecure=${TELEMETRY_ENDPOINT_INSECURE}
 GO_LINKER_FLAGS_OPTIMIZATIONS = -s -w
 GO_LINKER_FLAGS = $(GO_LINKER_FLAGS_OPTIMIZATIONS) $(GO_LINKER_FlAGS_VARS)
 

cmd/gateway/commands.go

@@ -4,6 +4,7 @@ import (
 	"errors"
 	"fmt"
 	"os"
+	"runtime/debug"
 	"strconv"
 	"time"
 
@@ -124,11 +125,13 @@ func createStaticModeCommand() *cobra.Command {
 			atom := zap.NewAtomicLevel()
 
 			logger := ctlrZap.New(ctlrZap.Level(atom))
+			commit, date, dirty := getBuildInfo()
 			logger.Info(
 				"Starting NGINX Gateway Fabric in static mode",
 				"version", version,
 				"commit", commit,
 				"date", date,
+				"dirty", dirty,
 			)
 			log.SetLogger(logger)
 
@@ -410,11 +413,13 @@ func createProvisionerModeCommand() *cobra.Command {
 		Hidden: true,
 		RunE: func(_ *cobra.Command, _ []string) error {
 			logger := ctlrZap.New()
+			commit, date, dirty := getBuildInfo()
 			logger.Info(
 				"Starting NGINX Gateway Fabric Provisioner",
 				"version", version,
 				"commit", commit,
 				"date", date,
+				"dirty", dirty,
 			)
 
 			return provisioner.StartManager(provisioner.Config{
@@ -495,3 +500,30 @@ func parseFlags(flags *pflag.FlagSet) ([]string, []string) {
 
 	return flagKeys, flagValues
 }
+
+type buildInfoFunc func() (info *debug.BuildInfo, ok bool)
+
+var buildInfo buildInfoFunc = debug.ReadBuildInfo
+
+func getBuildInfo() (commitHash string, commitTime string, dirtyBuild string) {
+	commitHash = "unknown"
+	commitTime = "unknown"
+	dirtyBuild = "unknown"
+
+	info, ok := buildInfo()
+	if !ok {
+		return
+	}
+	for _, kv := range info.Settings {
+		switch kv.Key {
+		case "vcs.revision":
+			commitHash = kv.Value
+		case "vcs.time":
+			commitTime = kv.Value
+		case "vcs.modified":
+			dirtyBuild = kv.Value
+		}
+	}
+
+	return
+}

cmd/gateway/commands_test.go

@@ -2,6 +2,7 @@ package main
 
 import (
 	"io"
+	"runtime/debug"
 	"testing"
 
 	. "github.com/onsi/gomega"
@@ -582,3 +583,59 @@ func TestParseFlags(t *testing.T) {
 	g.Expect(flagKeys).Should(Equal(expectedKeys))
 	g.Expect(flagValues).Should(Equal(expectedValues))
 }
+
+func TestGetBuildInfo(t *testing.T) {
+	g := NewWithT(t)
+	stubBuildInfo := func() (info *debug.BuildInfo, ok bool) {
+		return &debug.BuildInfo{
+			Settings: []debug.BuildSetting{
+				{Key: "vcs.revision", Value: "abc123"},
+				{Key: "vcs.time", Value: "2024-07-30T12:34:56Z"},
+				{Key: "vcs.modified", Value: "true"},
+			},
+		}, true
+	}
+
+	buildInfo = stubBuildInfo
+
+	commitHash, commitTime, dirtyBuild := getBuildInfo()
+
+	g.Expect(commitHash).To(Equal("abc123"))
+	g.Expect(commitTime).To(Equal("2024-07-30T12:34:56Z"))
+	g.Expect(dirtyBuild).To(Equal("true"))
+}
+
+func TestGetBuildInfoNoBuildInfo(t *testing.T) {
+	g := NewWithT(t)
+	stubBuildInfo := func() (info *debug.BuildInfo, ok bool) {
+		return nil, false
+	}
+
+	buildInfo = stubBuildInfo
+
+	commitHash, commitTime, dirtyBuild := getBuildInfo()
+
+	g.Expect(commitHash).To(Equal("unknown"))
+	g.Expect(commitTime).To(Equal("unknown"))
+	g.Expect(dirtyBuild).To(Equal("unknown"))
+}
+
+func TestGetBuildInfoMissingValue(t *testing.T) {
+	g := NewWithT(t)
+	stubBuildInfo := func() (info *debug.BuildInfo, ok bool) {
+		return &debug.BuildInfo{
+			Settings: []debug.BuildSetting{
+				{Key: "vcs.time", Value: "2024-07-30T12:34:56Z"},
+				{Key: "vcs.modified", Value: "true"},
+			},
+		}, true
+	}
+
+	buildInfo = stubBuildInfo
+
+	commitHash, commitTime, dirtyBuild := getBuildInfo()
+
+	g.Expect(commitHash).To(Equal("unknown"))
+	g.Expect(commitTime).To(Equal("2024-07-30T12:34:56Z"))
+	g.Expect(dirtyBuild).To(Equal("true"))
+}

cmd/gateway/main.go

@@ -8,8 +8,6 @@ import (
 // Set during go build.
 var (
 	version string
-	commit  string
-	date    string
 
 	// telemetryReportPeriod is the period at which telemetry reports are sent.
 	telemetryReportPeriod string