zylon-ai/private-gpt · error · RuntimeError

File transfer failed: {e}

Error message

File transfer failed: {e}

What it means

The catch-all wrapper in transfer_file(): any exception during the transfer — including the result.success-failure RuntimeError from line 505, transport errors from _client.run_code, or serialization problems building the transfer code — is logged and re-raised as RuntimeError('File transfer failed: <cause>') with the original chained. The interpolated message identifies the underlying failure.

Source

Thrown at private_gpt/components/tabular/pandasai_sandbox.py:508

            _csv_content = {csv_content!r}
            with open({filepath!r}, 'w') as _f:
                _f.write(_csv_content)
            print("File transferred: {filepath}")
        """
        ).strip()

        try:
            result = self._run(
                self._client.run_code(
                    transfer_code, SandboxCodeOptions(language="python")
                )
            )
            if not result.success:
                raise RuntimeError(f"File transfer failed: {result.error}")
            logger.debug("Successfully transferred file: %s", filename)
        except Exception as e:
            logger.error("Failed to transfer file %s: %s", filename, e)
            raise RuntimeError(f"File transfer failed: {e}") from e

    def get_file_content(self, filename: str) -> str | None:
        if not self._client:
            raise RuntimeError("Sandbox not started")

        temp_dir = f"/tmp/{self._user_id}"
        filepath = f"{temp_dir}/{filename}"

        read_code = textwrap.dedent(
            f"""
            import os
            _filepath = {filepath!r}
            if os.path.exists(_filepath):
                with open(_filepath, 'r') as _f:
                    _content = _f.read()
                print("FILE_CONTENT_START")
                print(_content)
                print("FILE_CONTENT_END")

View on GitHub (pinned to 4a030776a3)

Solutions

1. Check e.__cause__ to distinguish transport failure from in-sandbox write failure (error 250).
2. For expired sessions: restart the sandbox (start()) and retry the transfer once.
3. For serialization issues: sanitize the dataframe (drop/convert object columns with non-str values) before transfer.
4. Keep the interval between start() and transfers short to avoid session expiry.

Example fix

# before
sandbox.transfer_file(df, "ctx.csv")

# after
try:
    sandbox.transfer_file(df, "ctx.csv")
except RuntimeError as e:
    logger.warning("Transfer failed (%s); restarting sandbox and retrying", e)
    sandbox.stop()
    sandbox.start()
    sandbox.transfer_file(df, "ctx.csv")

try:
    sandbox.transfer_file(df, "ctx.csv")
except RuntimeError as e:
    logger.warning("transfer failed, restarting sandbox: %s", e)
    sandbox.stop(); sandbox.start()
    sandbox.transfer_file(df, "ctx.csv")  # one retry only

When it happens

Trigger: Transport-level failure calling run_code (connection dropped, sandbox session expired); the inner 'File transfer failed: {result.error}' being re-wrapped; exceptions building the transfer snippet (e.g. csv_content repr failing on exotic dtypes).

Common situations: Sandbox session timed out between start() and transfer_file(); network instability to the sandbox service; non-serializable cell values in the dataframe.

Related errors

• Failed to start sandbox: {e}
• Code execution failed: {message}
• Sandbox not started
• File transfer failed: {result.error}
• Path '{canonical_path}' does not match any session mount.

AI-assisted analysis of zylon-ai/private-gpt@4a030776a3 (2026-08-15). Data as JSON: /api/errors/21c2aace7c0e8ff6. Report an issue: GitHub.