docker/cli · error

invalid platform: %w

Error message

invalid platform: %w

What it means

Error "invalid platform: %w" thrown in docker/cli.

Source

Thrown at cli/command/image/save.go:62

	flags := cmd.Flags()

	flags.StringVarP(&opts.output, "output", "o", "", "Write to a file, instead of STDOUT")
	flags.StringSliceVar(&opts.platform, "platform", []string{}, `Save only the given platform(s). Formatted as a comma-separated list of "os[/arch[/variant]]" (e.g., "linux/amd64,linux/arm64/v8")`)
	_ = flags.SetAnnotation("platform", "version", []string{"1.48"})

	_ = cmd.RegisterFlagCompletionFunc("platform", completion.Platforms())
	return cmd
}

// runSave performs a save against the engine based on the specified options
func runSave(ctx context.Context, dockerCLI command.Cli, opts saveOptions) error {
	var options []client.ImageSaveOption

	platformList := []ocispec.Platform{}
	for _, p := range opts.platform {
		pp, err := platforms.Parse(p)
		if err != nil {
			return fmt.Errorf("invalid platform: %w", err)
		}
		platformList = append(platformList, pp)
	}
	if len(platformList) > 0 {
		options = append(options, client.ImageSaveWithPlatforms(platformList...))
	}

	var output io.Writer
	if opts.output == "" {
		if dockerCLI.Out().IsTerminal() {
			return errors.New("cowardly refusing to save to a terminal. Use the -o flag or redirect")
		}
		output = dockerCLI.Out()
	} else {
		writer, err := atomicwriter.New(opts.output, 0o600)
		if err != nil {
			return fmt.Errorf("failed to save image: %w", err)
		}

View on GitHub (pinned to e9452d6e78)

When it happens

Trigger: Thrown at cli/command/image/save.go:62 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of docker/cli@e9452d6e78 (2026-08-01). Data as JSON: /data/errors/ceb7a90cbb3ef14f.json. Report an issue: GitHub.