GoogleContainerTools/skaffold · error

getting relative tar paths: %w

Error message

getting relative tar paths: %w

What it means

CreateDockerTarContext wraps any failure from GetDependenciesCached with 'getting relative tar paths'. When Skaffold builds a tar.gz Docker build context it must first compute the dependency file list (which requires resolving and parsing the Dockerfile); a failure anywhere in that dependency resolution surfaces here. The root cause is always in the wrapped error — commonly a missing or unreadable Dockerfile.

Source

Thrown at pkg/skaffold/docker/context.go:31

See the License for the specific language governing permissions and
limitations under the License.
*/

package docker

import (
	"context"
	"fmt"
	"io"
	"path/filepath"

	"github.com/GoogleContainerTools/skaffold/v2/pkg/skaffold/util"
)

func CreateDockerTarContext(ctx context.Context, w io.Writer, buildCfg BuildConfig, cfg Config) error {
	paths, err := GetDependenciesCached(ctx, buildCfg, cfg)
	if err != nil {
		return fmt.Errorf("getting relative tar paths: %w", err)
	}

	var p []string
	for _, path := range paths {
		p = append(p, filepath.Join(buildCfg.workspace, path))
	}

	if err := util.CreateTar(ctx, w, buildCfg.workspace, p); err != nil {
		return fmt.Errorf("creating tar gz: %w", err)
	}

	return nil
}

View on GitHub (pinned to a1189de023)

Solutions

1. Read the wrapped error: it names the real failure (e.g. Dockerfile not found vs missing COPY source).
2. Verify dockerfilePath resolves from the workspace: check the artifact's 'docker.dockerfile' value and that the file exists.
3. Confirm all COPY/ADD sources in the Dockerfile exist relative to the workspace.
4. Check that the workspace path is correct and readable from where Skaffold runs.
5. If a stale cache entry is suspected, restart Skaffold to clear the in-memory dependency cache.

Example fix

// before
build:
  artifacts:
    - image: app
      docker:
        dockerfile: Dockerfile.prod   # file does not exist
// after
build:
  artifacts:
    - image: app
      docker:
        dockerfile: Dockerfile        # exists at workspace root

ws := buildCfg.workspace
df := buildCfg.dockerfilePath
if df == "" {
    df = "Dockerfile"
}
if _, err := os.Stat(filepath.Join(ws, df)); err != nil {
    return fmt.Errorf("Dockerfile %s not found in workspace %s: %w", df, ws, err)
}

func dockerfileExists(ws, dockerfilePath string) bool {
    if dockerfilePath == "" {
        dockerfilePath = "Dockerfile"
    }
    info, err := os.Stat(filepath.Join(ws, dockerfilePath))
    return err == nil && !info.IsDir()
}

err := CreateDockerTarContext(ctx, w, buildCfg, cfg)
if err != nil {
    if strings.Contains(err.Error(), "getting relative tar paths") {
        return fmt.Errorf("build context dependency resolution failed — check the Dockerfile path and COPY sources: %w", err)
    }
    return err
}

When it happens

Trigger: Calling CreateDockerTarContext where GetDependenciesCached fails: NormalizeDockerfilePath can't find the Dockerfile, or the Dockerfile can't be parsed for dependencies (bad COPY/ADD sources, missing files).

Common situations: dockerfilePath points to a non-existent file; workspace path is wrong; Dockerfile references COPY sources that don't exist; .dockerignore handling fails; cached dependency error replayed for the artifact.

Related errors

• creating docker context: %w
• creating docker context: %w
• creating tar gz: %w
• loading image into docker daemon: %w
• %q running container image %q errored during run with status

AI-assisted analysis of GoogleContainerTools/skaffold@a1189de023 (2026-09-05). Data as JSON: /api/errors/f08af1f9685c00ce. Report an issue: GitHub.