FoundationAgents/OpenManus · error · RuntimeError

Failed to extract file: {src_path}

Error message

Failed to extract file: {src_path}

What it means

Raised as RuntimeError by DockerSandbox.copy_from (app/sandbox/core/sandbox.py:305) when tar.extractfile(members[0]) returns None. extractfile returns None for members that carry no data stream — directories, symlinks, devices, FIFOs. So the archive's first member is not a regular file even though the tar had exactly one member.

Source

Thrown at app/sandbox/core/sandbox.py:305

                with tarfile.open(tar_path) as tar:
                    members = tar.getmembers()
                    if not members:
                        raise FileNotFoundError(f"Source file is empty: {src_path}")

                    # If destination is a directory, we should preserve relative path structure
                    if os.path.isdir(dst_path):
                        tar.extractall(dst_path)
                    else:
                        # If destination is a file, we only extract the source file's content
                        if len(members) > 1:
                            raise RuntimeError(
                                f"Source path is a directory but destination is a file: {src_path}"
                            )

                        with open(dst_path, "wb") as dst:
                            src_file = tar.extractfile(members[0])
                            if src_file is None:
                                raise RuntimeError(
                                    f"Failed to extract file: {src_path}"
                                )
                            dst.write(src_file.read())

        except docker.errors.NotFound:
            raise FileNotFoundError(f"Source file not found: {src_path}")
        except Exception as e:
            raise RuntimeError(f"Failed to copy file: {e}")

    async def copy_to(self, src_path: str, dst_path: str) -> None:
        """Copies a file to the container.

        Args:
            src_path: Source file path (host).
            dst_path: Destination path (container).

        Raises:
            FileNotFoundError: If source file does not exist.

View on GitHub (pinned to 52a13f2a57)

Solutions

1. Check what the source is: run_command(f"ls -ld {src_path}") — copy real files with copy_from or the whole tree as a directory dst.
2. If src is a symlink, resolve it in the container first (readlink) and copy the target.
3. Use a directory destination so tar.extractall handles mixed member types.

Example fix

# before
await sandbox.copy_from("latest", "./latest")  # 'latest' is a symlink -> RuntimeError

# after
target = (await sandbox.run_command("readlink -f latest")).strip()
await sandbox.copy_from(target, "./latest")

kind = (await sandbox.run_command(f"ls -ld {shlex.quote(src)}")).split()[0]
regular = kind.startswith("-")

try:
    await sandbox.copy_from(src, dst)
except RuntimeError as e:
    if "Failed to extract" in str(e):
        real = (await sandbox.run_command(f"readlink -f {shlex.quote(src)}")).strip()
        await sandbox.copy_from(real, dst)
    else:
        raise

When it happens

Trigger: src_path is a directory containing a single subdirectory (one member: the subdir entry); src is a symlink whose link target is the only member; special files (sockets/fifos) in the archive.

Common situations: Copying a path that is actually a symlink created by a build step; copying a directory with one empty subdir; docker get_archive on a path whose parent structure yields a non-regular first entry.

Related errors

• Source file is empty: {src_path}
• Source path is a directory but destination is a file: {src_p
• Failed to copy file: {e}
• Failed to read file: {e}
• Source file not found: {src_path}

AI-assisted analysis of FoundationAgents/OpenManus@52a13f2a57 (2026-08-15). Data as JSON: /api/errors/731a7df8fda9ed57. Report an issue: GitHub.