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# nemo_gym.artifacts.exporters.isolated

## Module Contents

### Classes

| Name                                                                                          | Description                                                                      |
| --------------------------------------------------------------------------------------------- | -------------------------------------------------------------------------------- |
| [`ExportPreparationError`](#nemo_gym-artifacts-exporters-isolated-ExportPreparationError)     | The run cannot be handed to an isolated exporter's worker; the message says why. |
| [`ExporterEnvironmentError`](#nemo_gym-artifacts-exporters-isolated-ExporterEnvironmentError) | The virtual environment an isolated exporter needs could not be built.           |
| [`IsolatedExporter`](#nemo_gym-artifacts-exporters-isolated-IsolatedExporter)                 | An exporter whose backend work runs in its own virtual environment.              |

### Functions

| Name                                                                                                | Description                                                                                   |
| --------------------------------------------------------------------------------------------------- | --------------------------------------------------------------------------------------------- |
| [`_worker_environment`](#nemo_gym-artifacts-exporters-isolated-_worker_environment)                 | This process's environment minus what would point the worker's Python back at Gym's packages. |
| [`ensure_exporter_environment`](#nemo_gym-artifacts-exporters-isolated-ensure_exporter_environment) | Build the exporter's virtual environment if it is not ready, and return its Python.           |
| [`exporter_venv_path`](#nemo_gym-artifacts-exporters-isolated-exporter_venv_path)                   | `<venv_root>/exporters/<name>/<digest of requirements>/.venv`.              |

### Data

[`WORKER_HARNESS_FPATH`](#nemo_gym-artifacts-exporters-isolated-WORKER_HARNESS_FPATH)

### API

```python
class nemo_gym.artifacts.exporters.isolated.ExportPreparationError()
```

**Bases:** `RuntimeError`

The run cannot be handed to an isolated exporter's worker; the message says why.

```python
class nemo_gym.artifacts.exporters.isolated.ExporterEnvironmentError()
```

**Bases:** `RuntimeError`

The virtual environment an isolated exporter needs could not be built.

```python
class nemo_gym.artifacts.exporters.isolated.IsolatedExporter(
    config: nemo_gym.config.config_types.RunExportConfig,
    venv_root: pathlib.Path
)
```

**Bases:** [Exporter](/nemo/gym/nemo-gym/nemo_gym/artifacts/exporters/base#nemo_gym-artifacts-exporters-base-Exporter)

An exporter whose backend work runs in its own virtual environment.

The SDK and its dependencies never enter Gym's environment, and an SDK that updates itself cannot disturb
it. The main process validates the config and prepares what the backend needs (`build_payload`); the worker,
a standalone file run with the environment's Python, does the backend call.

The payload goes to the worker as JSON on stdin and may carry credentials, which therefore stay out of the
process list. The worker file defines `run(payload) -> dict` and must not import `nemo_gym`.

**`requirements`** `tuple[str, ...] = ()`

---

**`venv_root`** `= Path(venv_root).resolve()`

---

**`worker_fpath`** `Path`

---

```python
nemo_gym.artifacts.exporters.isolated.IsolatedExporter._run_worker(
    python: pathlib.Path,
    payload: dict[str, typing.Any],
    workdir: pathlib.Path
) -> nemo_gym.artifacts.exporters.base.ExportResult
```

```python
nemo_gym.artifacts.exporters.isolated.IsolatedExporter.build_payload(
    artifacts: nemo_gym.artifacts.run_artifacts.RunArtifacts,
    workdir: pathlib.Path
) -> dict[str, typing.Any]
```

abstract

The JSON-serializable input for the worker. Files it stages go under `workdir`, removed afterwards.

Raise `ExportPreparationError` when the run cannot be exported.

```python
nemo_gym.artifacts.exporters.isolated.IsolatedExporter.export(
    artifacts: nemo_gym.artifacts.run_artifacts.RunArtifacts
) -> nemo_gym.artifacts.exporters.base.ExportResult
```

```python
nemo_gym.artifacts.exporters.isolated.IsolatedExporter.from_global_config(
    global_config_dict: omegaconf.DictConfig
) -> nemo_gym.artifacts.exporters.isolated.IsolatedExporter
```

classmethod

```python
nemo_gym.artifacts.exporters.isolated.IsolatedExporter.required_packages() -> tuple[str, ...]
```

```python
nemo_gym.artifacts.exporters.isolated.IsolatedExporter.worker_timeout_s(
    payload: dict[str, typing.Any]
) -> typing.Optional[float]
```

Seconds the worker may run before it is killed and the export fails; None for no limit.

A backend SDK can hang (a stalled upload, a retry loop), and an export that runs in a job script would
hold the job's allocation until then.

```python
nemo_gym.artifacts.exporters.isolated._worker_environment(
    python: pathlib.Path
) -> dict[str, str]
```

This process's environment minus what would point the worker's Python back at Gym's packages.

The exporter environment's `bin` leads `PATH`, so a bare `python` or an SDK-installed command resolves there.

```python
nemo_gym.artifacts.exporters.isolated.ensure_exporter_environment(
    venv_root: pathlib.Path,
    name: str,
    requirements: tuple[str, ...]
) -> pathlib.Path
```

Build the exporter's virtual environment if it is not ready, and return its Python.

Concurrent exports share one build: `setup_environment` serializes installers with a file lock and skips a
ready environment.

```python
nemo_gym.artifacts.exporters.isolated.exporter_venv_path(
    venv_root: pathlib.Path,
    name: str,
    requirements: tuple[str, ...]
) -> pathlib.Path
```

`<venv_root>/exporters/<name>/<digest of requirements>/.venv`.

Keying on the requirements gives a changed requirement list a fresh environment, while a given list keeps
its environment, which an SDK is free to update itself within.

```python
nemo_gym.artifacts.exporters.isolated.WORKER_HARNESS_FPATH = Path(__file__).with_name('_isolated_worker.py')
```