SupportBundles: Build tars in memory (#61581)

* build tar in memory

* match tag

pkg/services/supportbundles/supportbundlesimpl/service_bundle.go

@@ -6,11 +6,10 @@ import (
 	"compress/gzip"
 	"context"
 	"errors"
-	"fmt"
 	"io"
-	"os"
 	"path/filepath"
 	"runtime/debug"
+	"time"
 
 	"github.com/grafana/grafana/pkg/services/supportbundles"
 )
@@ -18,8 +17,8 @@ import (
 var ErrCollectorPanicked = errors.New("collector panicked")
 
 type bundleResult struct {
-	path string
-	err  error
+	tarBytes []byte
+	err      error
 }
 
 func (s *Service) startBundleWork(ctx context.Context, collectors []string, uid string) {
@@ -33,47 +32,43 @@ func (s *Service) startBundleWork(ctx context.Context, collectors []string, uid
 			}
 		}()
 
-		sbFilePath, err := s.bundle(ctx, collectors, uid)
+		bundleBytes, err := s.bundle(ctx, collectors, uid)
 		if err != nil {
 			result <- bundleResult{err: err}
 		}
-		result <- bundleResult{
-			path: sbFilePath,
-		}
+		result <- bundleResult{tarBytes: bundleBytes}
 		close(result)
 	}()
 
 	select {
 	case <-ctx.Done():
 		s.log.Warn("Context cancelled while collecting support bundle")
-		if err := s.store.Update(ctx, uid, supportbundles.StateTimeout, ""); err != nil {
+		if err := s.store.Update(ctx, uid, supportbundles.StateTimeout, nil); err != nil {
 			s.log.Error("failed to update bundle after timeout")
 		}
 		return
 	case r := <-result:
 		if r.err != nil {
-			if err := s.store.Update(ctx, uid, supportbundles.StateError, ""); err != nil {
+			s.log.Error("failed to make bundle", "error", r.err, "uid", uid)
+			if err := s.store.Update(ctx, uid, supportbundles.StateError, nil); err != nil {
 				s.log.Error("failed to update bundle after error")
 			}
 			return
 		}
-		if err := s.store.Update(ctx, uid, supportbundles.StateComplete, r.path); err != nil {
+		if err := s.store.Update(ctx, uid, supportbundles.StateComplete, r.tarBytes); err != nil {
 			s.log.Error("failed to update bundle after completion")
 		}
 		return
 	}
 }
 
-func (s *Service) bundle(ctx context.Context, collectors []string, uid string) (string, error) {
+func (s *Service) bundle(ctx context.Context, collectors []string, uid string) ([]byte, error) {
 	lookup := make(map[string]bool, len(collectors))
 	for _, c := range collectors {
 		lookup[c] = true
 	}
 
-	sbDir, err := os.MkdirTemp("", "")
-	if err != nil {
-		return "", err
-	}
+	files := map[string][]byte{}
 
 	for _, collector := range s.collectors {
 		if !lookup[collector.UID] && !collector.IncludedByDefault {
@@ -86,70 +81,42 @@ func (s *Service) bundle(ctx context.Context, collectors []string, uid string) (
 
 		// write item to file
 		if item != nil {
-			if err := os.WriteFile(filepath.Join(sbDir, item.Filename), item.FileBytes, 0600); err != nil {
-				s.log.Warn("Failed to collect support bundle item", "error", err)
-			}
+			files[item.Filename] = item.FileBytes
 		}
 	}
 
 	// create tar.gz file
 	var buf bytes.Buffer
-	errCompress := compress(sbDir, &buf)
+	errCompress := compress(files, &buf)
 	if errCompress != nil {
-		return "", errCompress
+		return nil, errCompress
 	}
 
-	finalFilePath := filepath.Join(sbDir, fmt.Sprintf("%s.tar.gz", uid))
-
-	// Ignore gosec G304 as this function is only used internally.
-	//nolint:gosec
-	fileToWrite, err := os.OpenFile(finalFilePath, os.O_CREATE|os.O_RDWR, 0600)
-	if err != nil {
-		return "", err
-	}
-	if _, err := io.Copy(fileToWrite, &buf); err != nil {
-		return "", err
-	}
-
-	return finalFilePath, nil
+	return buf.Bytes(), nil
 }
 
-func compress(src string, buf io.Writer) error {
+func compress(files map[string][]byte, buf io.Writer) error {
 	// tar > gzip > buf
 	zr := gzip.NewWriter(buf)
 	tw := tar.NewWriter(zr)
 
-	// walk through every file in the folder
-	err := filepath.Walk(src, func(file string, fi os.FileInfo, err error) error {
-		// if not a dir, write file content
-		if !fi.IsDir() {
-			// generate tar header
-			header, err := tar.FileInfoHeader(fi, file)
-			if err != nil {
-				return err
-			}
-
-			header.Name = filepath.ToSlash("/bundle/" + header.Name)
-
-			// write header
-			if err := tw.WriteHeader(header); err != nil {
-				return err
-			}
-
-			// Ignore gosec G304 as this function is only used internally.
-			//nolint:gosec
-			data, err := os.Open(file)
-			if err != nil {
-				return err
-			}
-			if _, err := io.Copy(tw, data); err != nil {
-				return err
-			}
+	for name, data := range files {
+		header := &tar.Header{
+			Name:    name,
+			ModTime: time.Now(),
+			Mode:    int64(0o644),
+			Size:    int64(len(data)),
+		}
+
+		header.Name = filepath.ToSlash("/bundle/" + header.Name)
+		// write header
+		if err := tw.WriteHeader(header); err != nil {
+			return err
+		}
+
+		if _, err := io.Copy(tw, bytes.NewReader(data)); err != nil {
+			return err
 		}
-		return nil
-	})
-	if err != nil {
-		return err
 	}
 
 	// produce tar