Merge branch 'sh-fix-gocloud-cache-modtime' into 'main'

Fix cache extractor redownloading up-to-date caches for Go Cloud URLs

See merge request https://gitlab.com/gitlab-org/gitlab-runner/-/merge_requests/5394

Merged-by: Stan Hu <[email protected]>
Approved-by: Axel von Bertoldi <[email protected]>
Reviewed-by: Axel von Bertoldi <[email protected]>

Author: stanhu

commands/helpers/cache_extractor.go

@@ -50,9 +50,13 @@ func (c *CacheExtractorCommand) getClient() *CacheClient {
 }
 
 func checkIfUpToDate(path string, resp *http.Response) (bool, time.Time) {
-	fi, _ := os.Lstat(path)
 	date, _ := time.Parse(http.TimeFormat, resp.Header.Get("Last-Modified"))
-	return fi != nil && !date.After(fi.ModTime()), date
+	return isLocalCacheFileUpToDate(path, date), date
+}
+
+func isLocalCacheFileUpToDate(path string, date time.Time) bool {
+	fi, _ := os.Lstat(path)
+	return fi != nil && !date.After(fi.ModTime())
 }
 
 func getRemoteCacheSize(resp *http.Response) int64 {
@@ -151,6 +155,11 @@ func (c *CacheExtractorCommand) handleGoCloudURL() error {
 		return err
 	}
 
+	if isLocalCacheFileUpToDate(c.File, attrs.ModTime) {
+		logrus.Infoln(filepath.Base(c.File), "is up to date")
+		return nil
+	}
+
 	reader, err := b.NewReader(ctx, objectName, nil)
 	if err != nil {
 		return err

commands/helpers/cache_extractor_test.go

@@ -288,3 +288,25 @@ func TestCacheExtractorRemoteServerFailOnInvalidServer(t *testing.T) {
 	_, err := os.Stat(cacheExtractorTestArchivedFile)
 	assert.Error(t, err)
 }
+
+func TestIsLocalCacheFileUpToDate(t *testing.T) {
+	tmpDir := t.TempDir()
+	cacheFile := path.Join(tmpDir, "cache-file")
+
+	// Create cache file
+	err := os.WriteFile(cacheFile, []byte("test content"), 0644)
+	require.NoError(t, err)
+
+	// Set a specific modification time
+	modTime := time.Now()
+	err = os.Chtimes(cacheFile, modTime, modTime)
+	require.NoError(t, err)
+
+	// Test when remote file is older (cache is up to date)
+	result := isLocalCacheFileUpToDate(cacheFile, modTime.Add(-1*time.Hour))
+	require.True(t, result, "Cache should be up to date when remote file is older")
+
+	// Test when remote file is newer (cache is outdated)
+	result = isLocalCacheFileUpToDate(cacheFile, modTime.Add(1*time.Hour))
+	require.False(t, result, "Cache should be outdated when remote file is newer")
+}