docker/compose · error

destination "%s:%s" must be a directory

Error message

destination "%s:%s" must be a directory

What it means

Error "destination "%s:%s" must be a directory" thrown in docker/compose.

Source

Thrown at pkg/compose/cp.go:207

	// path exists, in which case the copy may still succeed. If there is any
	// type of conflict (e.g., non-directory overwriting an existing directory
	// or vice versa) the extraction will fail. If the destination simply did
	// not exist, but the parent directory does, the extraction will still
	// succeed.
	if err == nil {
		dstInfo.Exists, dstInfo.IsDir = true, dstStat.Mode.IsDir()
	}

	var (
		content         io.Reader
		resolvedDstPath string
	)

	if srcPath == "-" {
		content = s.stdin()
		resolvedDstPath = dstInfo.Path
		if !dstInfo.IsDir {
			return fmt.Errorf("destination \"%s:%s\" must be a directory", containerID, dstPath)
		}
	} else {
		// Prepare source copy info.
		srcInfo, err := archive.CopyInfoSourcePath(srcPath, opts.FollowLink)
		if err != nil {
			return err
		}

		srcArchive, err := archive.TarResource(srcInfo)
		if err != nil {
			return err
		}
		defer srcArchive.Close() //nolint:errcheck

		// With the stat info about the local source as well as the
		// destination, we have enough information to know whether we need to
		// alter the archive that we upload so that when the server extracts
		// it to the specified directory in the container we get the desired

View on GitHub (pinned to ddc4b044b6)

Solutions

1. Point the destination at an existing directory inside the container, ending the path with a slash if needed.
2. Create the directory in the container first with docker compose exec <service> mkdir -p <path>.

When it happens

Trigger: When copying multiple source files into a container with 'docker compose cp', the in-container destination must be an existing directory and it is not.

Common situations: Multiple sources (or a wildcard-expanded copy) were given with a destination path that is a file or does not exist inside the container.

AI-assisted analysis of docker/compose@ddc4b044b6 (2026-08-15). Data as JSON: /api/errors/439268308eaf9bdc. Report an issue: GitHub.