Skip to main content

cwsandbox-client

A Python client library for CWSandboxes.

Documentation

See the documentation site for the full tutorial, guides, and API reference.

Quick Start

from cwsandbox import Sandbox

# Quick one-liner with factory method (sync/async hybrid API)
sb = Sandbox.run("echo", "Hello, World!")
sb.stop().result()  # Block for completion

# Context manager for automatic cleanup
with Sandbox.run("sleep", "infinity", container_image="python:3.11") as sb:
    result = sb.exec(["python", "-c", "print(2 + 2)"]).result()
    print(result.stdout)  # 4

# Also works in async contexts
async with Sandbox.run("sleep", "infinity") as sb:
    result = await sb.exec(["python", "-c", "print(2 + 2)"])
    print(result.stdout)  # 4

Sandbox data connections

Exec, log, and file operations prefer a sandbox-scoped direct mTLS connection. Lifecycle and management operations continue to use the CWSandbox API. The SDK generates the private key in memory, sends only a certificate signing request, and never sends API bearer credentials to the sandbox data endpoint.

The default auto policy uses a short direct-connect budget, then falls back to the API gateway. You can require either path for validation or rollback:

from cwsandbox import DataPlaneMode, Sandbox, SandboxDefaults

# Fail instead of falling back, useful when validating direct connectivity.
with Sandbox.run(data_plane_mode=DataPlaneMode.DIRECT) as sb:
    print(sb.exec(["echo", "direct"]).result().stdout)

# Disable direct access for a group of sandboxes.
defaults = SandboxDefaults(data_plane_mode=DataPlaneMode.GATEWAY)
with Sandbox.run(defaults=defaults) as sb:
    print(sb.exec(["echo", "gateway"]).result().stdout)

Direct credentials are scoped to the requested operation and created lazily. Active streams retain their connection, while a process-wide bounded idle-channel cache prevents large collections of inactive sandbox objects from retaining one socket per sandbox.

Authentication

Authentication defaults to AuthStrategy.COREWEAVE_API_KEY, which reads CWSANDBOX_API_KEY and sends it as a Bearer token. The strategy argument is optional, so existing callers do not need to change.

To use W&B credentials, install the optional integration and select it explicitly. Credential resolution is delegated to the W&B SDK and supports an active W&B session, WANDB_API_KEY, and the host-specific entry in .netrc:

pip install "cwsandbox[wandb]"
from cwsandbox import AuthStrategy, Sandbox

with Sandbox.run(auth=AuthStrategy.WANDB) as sb:
    ...

W&B authentication is sent in the x-wandb-api-key header; it is not treated as a CoreWeave Bearer token.

Embedding in a long-running host

Scripts and CLIs keep the default: the first owned sandbox registers atexit and, on the main thread, SIGINT/SIGTERM handlers so a signal can stop Sessions and exit.

Long-running hosts that already own process lifecycle should disable those signal handlers before creating a sandbox. atexit still runs on normal process exit. The host is responsible for graceful shutdown and for explicitly stopping sandboxes it owns.

import cwsandbox

cwsandbox.disable_signal_handlers()
CWSANDBOX_DISABLE_SIGNAL_HANDLERS=1

Accepted environment values: 1, true, yes, on (case-insensitive). Configure the API or environment variable before the first owned sandbox; changing the variable afterward has no effect.

Development

See DEVELOPMENT.md for setup and workflow.

For code standards and commit guidelines, see CONTRIBUTING.md.

License

  • The CWSandbox Client library is licensed under the Apache-2.0 license.
  • The CWSandbox Client examples are licensed under the BSD-3-Clause license.

Release files for cwsandbox 1.15.1

For a detailed explanation of source distributions (sdists) and built distributions (wheels), please see the package formats documentation.

Source distribution (sdist)

Source distribution for cwsandbox 1.15.1
File Size Uploaded
cwsandbox-1.15.1.tar.gz 648.0 kB Details

Built distribution (wheel)

Table of built distributions (wheels) for cwsandbox 1.15.1
File Interpreter ABI Platform
cwsandbox-1.15.1-py3-none-any.whl Python 3 none any Details

Total release size: 901.7 kB

Release files / cwsandbox-1.15.1.tar.gz

Download URL cwsandbox-1.15.1.tar.gz
Size 648.0 kB
Tags Source
SHA-256 checksum
How to use checksums
3662b74ba65817f3c1d46cd6d8c2eacd37732fd9cd83af7aff5a533913f0a5f6
BLAKE2b-256 checksum
How to use checksums
e34c14f2618bbfea04b217d23a7f6ec898d671aab62b8ceef379be5707b47dd7
Upload date
Uploaded using Trusted Publishing?
What is trusted publishing?
Yes
Uploaded via twine/7.0.0 CPython/3.13.14

Provenance

Provenance describes where a file came from. On PyPI, provenance is shared via attestations, which provide a verifiable record of the build or publishing details. View details, limitations and caveats.

PyPI Publish Attestation

PyPI verified that this artifact, at this checksum, originated from the publisher listed below.

Signed by GitHub Actions, verified by PyPI on Sep 25, 2026.

Transparency log

Release files / cwsandbox-1.15.1-py3-none-any.whl

Download URL cwsandbox-1.15.1-py3-none-any.whl
Size 253.7 kB
Tags Python 3
SHA-256 checksum
How to use checksums
1a38c3ea01639beb078eb94d6f62c4d80ab7f1074227876cd38cea2ee7159a11
BLAKE2b-256 checksum
How to use checksums
c46f405bfeee491c64359c20469f51acd1d23738303a0ac28ae5755abddfea19
Upload date
Uploaded using Trusted Publishing?
What is trusted publishing?
Yes
Uploaded via twine/7.0.0 CPython/3.13.14

Provenance

Provenance describes where a file came from. On PyPI, provenance is shared via attestations, which provide a verifiable record of the build or publishing details. View details, limitations and caveats.

PyPI Publish Attestation

PyPI verified that this artifact, at this checksum, originated from the publisher listed below.

Signed by GitHub Actions, verified by PyPI on Sep 25, 2026.

Transparency log

Release history Release notifications | RSS feed

This release

1.15.1 This release

2 release files

1.15.0

2 release files

1.14.4

2 release files

1.14.3

2 release files

1.9.0

2 release files

1.8.0

2 release files

1.7.0

2 release files

1.6.0

2 release files

1.5.0

2 release files

1.4.0

2 release files

1.3.0

2 release files

1.2.0

2 release files

1.1.1

2 release files

1.1.0

2 release files

1.0.0

2 release files

0.28.0

2 release files

0.27.0

2 release files

0.26.2

2 release files

0.26.1

2 release files

0.26.0

2 release files

0.24.0

2 release files

0.23.3

2 release files

0.23.2

2 release files

0.23.1

2 release files

0.22.0

2 release files

0.21.0

2 release files

0.20.0

2 release files

0.19.3

2 release files

0.19.2

2 release files

0.19.1

2 release files

0.19.0

2 release files

0.18.0

2 release files

0.17.0

2 release files

0.12.2

2 release files

0.12.1

2 release files

0.12.0

2 release files

0.11.2

2 release files

0.11.1

2 release files

0.11.0

2 release files

0.10.0

2 release files

0.9.0

2 release files

Anthropic, PBC Visionary sponsor Bloomberg Visionary sponsor Hudson River Trading Visionary sponsor Meta Visionary sponsor NVIDIA Visionary sponsor Microsoft Sustainability sponsor Depot Continuous Integration AWS Cloud computing and Security Sponsor Datadog Monitoring Fastly CDN Google Download Analytics Sentry Error logging StatusPage Status page