Add go buildinfo to velero to assist with vmware-tanzu#8397

Dockerfile

@@ -26,16 +26,23 @@ ARG TARGETOS
 ARG TARGETARCH
 ARG TARGETVARIANT
 
+# GOTOOLCHAIN=auto allows the build to use the latest toolchain from the image instead of specified in go.mod
 ENV CGO_ENABLED=0 \
     GO111MODULE=on \
     GOPROXY=${GOPROXY} \
     GOOS=${TARGETOS} \
     GOARCH=${TARGETARCH} \
     GOARM=${TARGETVARIANT} \
+    GOTOOLCHAIN=auto \
     LDFLAGS="-X ${PKG}/pkg/buildinfo.Version=${VERSION} -X ${PKG}/pkg/buildinfo.GitSHA=${GIT_SHA} -X ${PKG}/pkg/buildinfo.GitTreeState=${GIT_TREE_STATE} -X ${PKG}/pkg/buildinfo.ImageRegistry=${REGISTRY}"
-
+    
 WORKDIR /go/src/github.com/vmware-tanzu/velero
 
+# Cache dependency downloads
+COPY go.mod  /go/src/github.com/vmware-tanzu/velero/go.mod
+COPY go.sum /go/src/github.com/vmware-tanzu/velero/go.sum
+RUN go mod download
+
 COPY . /go/src/github.com/vmware-tanzu/velero
 
 RUN mkdir -p /output/usr/bin && \
@@ -45,6 +52,15 @@ RUN mkdir -p /output/usr/bin && \
     go build -o /output/velero-helper \
     -ldflags "${LDFLAGS}" ${PKG}/cmd/velero-helper && \
     go clean -modcache -cache
+# check container image go version is used to build rather than toolchain from go.mod
+RUN export goCliVersion=$(go version | cut -d ' ' -f 3) && \
+    export veleroClientGoBuildInfoVersion=$(/output/${BIN} version --client-only) && \
+    echo "go version: $goCliVersion" && \
+    echo "velero client go version: $veleroClientGoBuildInfoVersion" && \
+    if [ $(go version | cut -d " " -f 3) = $(/output/${BIN} version --client-only | grep "Go version" | cut -d " " -f 3) ]; then \
+        echo "equal"; \
+    else (echo "not building using latest toolchain from image" >&2 && exit 1); \
+    fi
 
 # Restic binary build section
 FROM --platform=$BUILDPLATFORM golang:1.22-bookworm AS restic-builder
@@ -61,7 +77,13 @@ ENV CGO_ENABLED=0 \
     GOPROXY=${GOPROXY} \
     GOOS=${TARGETOS} \
     GOARCH=${TARGETARCH} \
-    GOARM=${TARGETVARIANT}
+    GOARM=${TARGETVARIANT} \
+    GOTOOLCHAIN=auto
+
+# Cache dependency downloads
+COPY go.mod  /go/src/github.com/vmware-tanzu/velero/go.mod
+COPY go.sum /go/src/github.com/vmware-tanzu/velero/go.sum
+RUN cd /go/src/github.com/vmware-tanzu/velero/ && go mod download
 
 COPY . /go/src/github.com/vmware-tanzu/velero
 

go.mod

@@ -1,5 +1,9 @@
 module github.com/vmware-tanzu/velero
 
+// Do not pin patch version here. Leave patch at X.Y.0
+// Use env GOTOOLCHAIN=auto to use newer of go cli used to build Velero.
+// or GOTOOLCHAIN=goX.Y.Z to use a specific toolchain version
+// See: https://go.dev/doc/toolchain#select and https://github.com/vmware-tanzu/velero/issues/8397
 go 1.22.0
 
 require (

pkg/buildinfo/buildinfo.go

@@ -19,12 +19,18 @@ limitations under the License.
 // worrying about introducing circular dependencies.
 package buildinfo
 
-import "fmt"
+import (
+	"fmt"
+	"runtime/debug"
+)
 
 var (
 	// Version is the current version of Velero, set by the go linker's -X flag at build time.
 	Version string
 
+	// goVersion is the version of Go that was used to build Velero
+	goBuildInfo *debug.BuildInfo
+
 	// GitSHA is the actual commit that is being built, set by the go linker's -X flag at build time.
 	GitSHA string
 
@@ -44,3 +50,14 @@ func FormattedGitSHA() string {
 	}
 	return GitSHA
 }
+
+func GoVersion() string {
+	if goBuildInfo == nil {
+		var ok bool
+		goBuildInfo, ok = debug.ReadBuildInfo()
+		if !ok {
+			return "cannot read Go BuildInfo"
+		}
+	}
+	return goBuildInfo.GoVersion
+}

pkg/cmd/cli/version/version.go

@@ -69,6 +69,7 @@ func printVersion(w io.Writer, clientOnly bool, kbClient kbclient.Client, server
 	fmt.Fprintln(w, "Client:")
 	fmt.Fprintf(w, "\tVersion: %s\n", buildinfo.Version)
 	fmt.Fprintf(w, "\tGit commit: %s\n", buildinfo.FormattedGitSHA())
+	fmt.Fprintf(w, "\tGo version: %s\n", buildinfo.GoVersion())
 
 	if clientOnly {
 		return

pkg/cmd/server/server.go

@@ -109,7 +109,7 @@ func NewCommand(f client.Factory) *cobra.Command {
 
 			logger.Infof("setting log-level to %s", strings.ToUpper(logLevel.String()))
 
-			logger.Infof("Starting Velero server %s (%s)", buildinfo.Version, buildinfo.FormattedGitSHA())
+			logger.Infof("Starting Velero server %s (%s) go-version: %s", buildinfo.Version, buildinfo.FormattedGitSHA(), buildinfo.GoVersion())
 			if len(features.All()) > 0 {
 				logger.Infof("%d feature flags enabled %s", len(features.All()), features.All())
 			} else {