Avoid reuploading unchanged files (#352)

go.sum

@@ -471,7 +471,6 @@ golang.org/x/sys v0.0.0-20210615035016-665e8c7367d1/go.mod h1:oPkhp1MJrh7nUepCBc
 golang.org/x/sys v0.0.0-20210616094352-59db8d763f22/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.0.0-20210630005230-0f9fa26af87c/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.0.0-20210806184541-e5e7981a1069/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
-golang.org/x/sys v0.0.0-20211216021012-1d35b9e2eb4e/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.0.0-20220209214540-3681064d5158 h1:rm+CHSpPEEW2IsXUib1ThaHIjuBVZjxNgSKmBLFfD4c=
 golang.org/x/sys v0.0.0-20220209214540-3681064d5158/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/term v0.0.0-20201117132131-f5c789dd3221/go.mod h1:Nr5EML6q2oocZ2LXRh80K7BxOlk5/8JxuGnuhpl+muw=

phase/upload_binaries.go

@@ -1,6 +1,9 @@
 package phase
 
 import (
+	"fmt"
+	"os"
+
 	"github.com/k0sproject/k0sctl/pkg/apis/k0sctl.k0sproject.io/v1beta1"
 	"github.com/k0sproject/k0sctl/pkg/apis/k0sctl.k0sproject.io/v1beta1/cluster"
 	"github.com/k0sproject/rig/exec"
@@ -38,15 +41,28 @@ func (p *UploadBinaries) Run() error {
 }
 
 func (p *UploadBinaries) uploadBinary(h *cluster.Host) error {
-	log.Infof("%s: uploading k0s binary from %s", h, h.UploadBinaryPath)
-	if err := h.Upload(h.UploadBinaryPath, h.Configurer.K0sBinaryPath(), exec.Sudo(h)); err != nil {
-		return err
+	stat, err := os.Stat(h.UploadBinaryPath)
+	if err != nil {
+		return fmt.Errorf("failed to stat %s: %w", h.UploadBinaryPath, err)
+	}
+	if h.FileChanged(h.UploadBinaryPath, h.Configurer.K0sBinaryPath()) {
+		log.Infof("%s: uploading k0s binary from %s", h, h.UploadBinaryPath)
+		if err := h.Upload(h.UploadBinaryPath, h.Configurer.K0sBinaryPath(), exec.Sudo(h)); err != nil {
+			return err
+		}
+	} else {
+		log.Infof("%s: k0s binary %s already exists on the target and hasn't been changed, skipping upload", h, h.UploadBinaryPath)
 	}
 
 	if err := h.Configurer.Chmod(h, h.Configurer.K0sBinaryPath(), "0700", exec.Sudo(h)); err != nil {
 		return err
 	}
 
+	log.Debugf("%s: touching %s", h, h.Configurer.K0sBinaryPath())
+	if err := h.Configurer.Touch(h, h.Configurer.K0sBinaryPath(), stat.ModTime(), exec.Sudo(h)); err != nil {
+		return fmt.Errorf("failed to touch %s: %w", h.Configurer.K0sBinaryPath(), err)
+	}
+
 	h.Metadata.K0sBinaryVersion = p.Config.Spec.K0s.Version
 
 	return nil

phase/uploadfiles.go

@@ -2,6 +2,7 @@ package phase
 
 import (
 	"fmt"
+	"os"
 	"path"
 
 	"github.com/alessio/shellescape"
@@ -107,8 +108,12 @@ func (p *UploadFiles) uploadFile(h *cluster.Host, f *cluster.UploadFile) error {
 			return err
 		}
 
-		if err := h.Upload(path.Join(f.Base, s.Path), dest, exec.Sudo(h)); err != nil {
-			return err
+		if h.FileChanged(src, dest) {
+			if err := h.Upload(path.Join(f.Base, s.Path), dest, exec.Sudo(h)); err != nil {
+				return err
+			}
+		} else {
+			log.Infof("%s: file already exists and hasn't been changed, skipping upload", h)
 		}
 
 		if owner != "" {
@@ -121,6 +126,14 @@ func (p *UploadFiles) uploadFile(h *cluster.Host, f *cluster.UploadFile) error {
 		if err := h.Configurer.Chmod(h, dest, s.PermMode, exec.Sudo(h)); err != nil {
 			return err
 		}
+		stat, err := os.Stat(src)
+		if err != nil {
+			return fmt.Errorf("failed to stat %s: %s", src, err)
+		}
+		log.Debugf("%s: touching %s", h, dest)
+		if err := h.Configurer.Touch(h, dest, stat.ModTime(), exec.Sudo(h)); err != nil {
+			return fmt.Errorf("failed to touch %s: %w", dest, err)
+		}
 	}
 
 	return nil

pkg/apis/k0sctl.k0sproject.io/v1beta1/cluster/host.go

@@ -3,6 +3,7 @@ package cluster
 import (
 	"encoding/json"
 	"fmt"
+	gos "os"
 	"regexp"
 	"strconv"
 	"strings"
@@ -112,6 +113,8 @@ type configurer interface {
 	TempFile(os.Host) (string, error)
 	UpdateServiceEnvironment(os.Host, string, map[string]string) error
 	CleanupServiceEnvironment(os.Host, string) error
+	Stat(os.Host, string, ...exec.Option) (*os.FileInfo, error)
+	Touch(os.Host, string, time.Time, ...exec.Option) error
 }
 
 // HostMetadata resolved metadata for host
@@ -494,3 +497,30 @@ func (h *Host) WaitKubeAPIReady(port int) error {
 	// thus we need to accept both 200 and 401 as valid statuses when checking kube api
 	return h.WaitHTTPStatus(fmt.Sprintf("https://localhost:%d/version", port), 200, 401)
 }
+
+// FileChanged returns true when a remote file has different size or mtime compared to local
+// or if an error occurs
+func (h *Host) FileChanged(lpath, rpath string) bool {
+	lstat, err := gos.Stat(lpath)
+	if err != nil {
+		log.Debugf("%s: local stat failed: %s", h, err)
+		return true
+	}
+	rstat, err := h.Configurer.Stat(h, rpath, exec.Sudo(h))
+	if err != nil {
+		log.Debugf("%s: remote stat failed: %s", h, err)
+		return true
+	}
+
+	if lstat.Size() != rstat.Size() {
+		log.Debugf("%s: file sizes for %s differ (%d vs %d)", h, lpath, lstat.Size(), rstat.Size())
+		return true
+	}
+
+	if !lstat.ModTime().Equal(rstat.ModTime()) {
+		log.Debugf("%s: file modtimes for %s differ (%s vs %s)", h, lpath, lstat.ModTime(), rstat.ModTime())
+		return true
+	}
+
+	return false
+}