coreweave/cwsandbox-client v0.12.0

v0.12.0

Repository: coreweave/cwsandbox-client

Tag: v0.12.0

Published: 2026-03-25T21:17:49Z

Prerelease: no

Release notes:

v0.12.0 (2026-03-25)

_This release is published under the Apache-2.0 License._

Bug Fixes

• sandbox: Always enqueue output sentinel on cancellation (`e680f4c`)

CancelledError is a BaseException, bypassing the except Exception handler. The if not cancelled guard in the finally block skipped the output_queue sentinel, leaving StreamReader consumers hanging forever. Remove the guard so the sentinel is always enqueued.

Fixes both _exec_streaming_async and _exec_streaming_tty_async.

Documentation

• Add interactive shells guide (`1ecd912`)

Cover SDK shell() usage, terminal resize, stdin/stdout streaming, and a comparison table for choosing between exec and shell.

Features

• cli: Add shell command (`0838e2a`)

Remote debugging and interactive workflows need direct terminal access to sandboxes without writing Python.

Add cwsandbox sh with raw mode, SIGWINCH resize, and terminal state restore on exit.

• sandbox: Add TTY exec and shell method (`8ff5de4`)

Add _exec_streaming_tty_async for raw-byte TTY streaming with resize support, and the public shell() method that returns a TerminalSession. Widen _on_exec_complete to accept TerminalResult.

• types: Add terminal types (`94e55a5`)

Make StreamReader a Generic[_S] parameterized over str (text streams) and bytes (raw TTY output). Add TerminalResult and TerminalSession types for interactive TTY sessions. Update Waitable type alias and __all__ exports.

Testing

• sandbox: Add TTY streaming tests (`2602959`)

Cover _exec_streaming_tty_async paths: happy path, server errors, gRPC transport errors, stdin forwarding, resize, and early failure propagation. Fold TestShellCancellation into the new class with shared helpers to reduce setup duplication.

• sandbox: Add xfail test for cancelled TTY session output hang (`8d665d8`)

Demonstrates a bug where cancelling a TerminalSession future leaves the output StreamReader hanging forever. The CancelledError path in _exec_streaming_tty_async skips the output_queue sentinel (if not cancelled), so consumers block indefinitely.

The fix is to remove the if not cancelled guard so the sentinel is always enqueued. Cross-review confirmed no double-sentinel risk.

Marked xfail(strict=True) — will flip to XPASS once the guard is removed, signaling the marker should be dropped.

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Detailed Changes: v0.11.2...v0.12.0