OpenSandbox Server

A production-grade, FastAPI-based service for managing the lifecycle of containerized sandboxes. It acts as the control plane to create, run, monitor, and dispose isolated execution environments across container platforms.

Features

Core capabilities

Lifecycle APIs: Standardized REST interfaces for create, start, pause, resume, delete
Pluggable runtimes:
- Docker: Production-ready
- Kubernetes: Production-ready (see Kubernetes Controller for deployment)
Lifecycle cleanup modes: Configurable TTL with renewal, or manual cleanup with explicit delete
Access control: API Key authentication (OPEN-SANDBOX-API-KEY); can be disabled for local/dev
Networking modes:
- Host: shared host network, performance first
- Bridge: isolated network with built-in HTTP routing
Resource quotas: CPU/memory limits with Kubernetes-style specs
Observability: Unified status with transition tracking
Registry support: Public and private images

Extended capabilities

Async provisioning: Background creation to reduce latency
Timer restoration: Expiration timers restored after restart
Env/metadata injection: Per-sandbox environment and metadata
Port resolution: Dynamic endpoint generation
Structured errors: Standard error codes and messages

WARNING

Metadata keys under the reserved prefix opensandbox.io/ are system-managed and cannot be supplied by users.

Requirements

Python: 3.10 or higher
Package Manager: uv (recommended) or pip
Runtime Backend:
- Docker Engine 20.10+ (for Docker runtime)
- Kubernetes 1.21.1+ (for Kubernetes runtime)
Operating System: Linux, macOS, or Windows with WSL2

Quick Start

Installation

Install from PyPI. For local development, clone the repo and run uv sync in server/.

bash

uv pip install opensandbox-server

Configuration

The server reads a TOML file. Default path: ~/.sandbox.toml. Override with SANDBOX_CONFIG_PATH or opensandbox-server --config /path/to/sandbox.toml.

Generate a starter file (see opensandbox-server -h for all flags):

bash

opensandbox-server init-config ~/.sandbox.toml --example docker
# Kubernetes: --example k8s  (deploy the operator / CRDs per kubernetes/ first)
# Locales: docker-zh | k8s-zh  |  omit --example for a schema-only skeleton  |  add --force to overwrite

Edit the file for your environment. Full reference: configuration.md (all keys, defaults, validation, env vars).
Topics covered there include: Docker network_mode / host_ip (e.g. server in Docker Compose), [egress] when clients send networkPolicy, [ingress], [secure_runtime], Kubernetes workload_provider / batchsandbox_template_file, [agent_sandbox], TTL caps, [renew_intent]. The server-wide persistence backend is configured under [store]; by default OpenSandbox uses a local SQLite database at ~/.opensandbox/opensandbox.db for server-managed metadata such as snapshot records.

Run the server

bash

opensandbox-server
# opensandbox-server --config /path/to/sandbox.toml

Listens on server.host / server.port from your TOML (defaults in configuration.md).

Health check (adjust host/port if you changed them):

bash

curl http://127.0.0.1:8080/health
# -> {"status": "healthy"}

API Documentation

Once the server is running, interactive API documentation is available:

Swagger UI: http://localhost:8080/docs
ReDoc: http://localhost:8080/redoc

API Authentication

Authentication is enforced only when server.api_key is set. If the value is empty or missing, the middleware skips API Key checks; however startup requires explicit risk acknowledgment. In interactive TTY mode, type YES when prompted. In non-interactive environments (Docker/Kubernetes/CI), set OPENSANDBOX_INSECURE_SERVER=YES to proceed. For production, always set a non-empty server.api_key and send it via the OPEN-SANDBOX-API-KEY header.

WARNING

Strongly recommend enabling server.api_key. See security report Issue #750.

All API endpoints (except /health, /docs, /redoc) require authentication via the OPEN-SANDBOX-API-KEY header when authentication is enabled:

bash

curl -H "OPEN-SANDBOX-API-KEY: your-secret-api-key" http://localhost:8080/v1/sandboxes

Example Usage

Create a Sandbox

bash

curl -X POST "http://localhost:8080/v1/sandboxes" \
  -H "OPEN-SANDBOX-API-KEY: your-secret-api-key" \
  -H "Content-Type: application/json" \
  -d '{
    "image": {
      "uri": "python:3.11-slim"
    },
    "entrypoint": [
      "python",
      "-m",
      "http.server",
      "8000"
    ],
    "timeout": 3600,
    "resourceLimits": {
      "cpu": "500m",
      "memory": "512Mi"
    },
    "env": {
      "PYTHONUNBUFFERED": "1"
    },
    "metadata": {
      "team": "backend",
      "project": "api-testing"
    }
  }'

Response:

json

{
  "id": "a1b2c3d4-5678-90ab-cdef-1234567890ab",
  "status": {
    "state": "Pending",
    "reason": "CONTAINER_STARTING",
    "message": "Sandbox container is starting.",
    "lastTransitionAt": "2024-01-15T10:30:00Z"
  },
  "metadata": {
    "team": "backend",
    "project": "api-testing"
  },
  "expiresAt": "2024-01-15T11:30:00Z",
  "createdAt": "2024-01-15T10:30:00Z",
  "entrypoint": ["python", "-m", "http.server", "8000"]
}

Other lifecycle calls (same OPEN-SANDBOX-API-KEY header): GET /v1/sandboxes/{id}, POST /v1/sandboxes/{id}/pause, POST /v1/sandboxes/{id}/resume, GET /v1/sandboxes/{id}/endpoints/{port} (append ?use_server_proxy=true when needed), POST .../renew-expiration, DELETE /v1/sandboxes/{id}. Full request/response shapes: Swagger UI above or OpenAPI under specs/.

For Kubernetes-backed sandboxes, pause/resume is implemented via BatchSandbox.spec.pause and internal SandboxSnapshot resources. The externally visible lifecycle transitions are Running -> Pausing -> Paused -> Resuming -> Running.

secureAccess currently applies only to Kubernetes sandboxes exposed through ingress gateway mode. Direct endpoint exposure, including non-gateway ingress configurations, is not supported for secured access.

Architecture

Component Responsibilities

API Layer (opensandbox_server/api/): HTTP request handling, validation, and response formatting
Service Layer (opensandbox_server/services/): Business logic for sandbox lifecycle operations
Middleware (opensandbox_server/middleware/): Cross-cutting concerns (authentication, logging)
Configuration (opensandbox_server/config.py): Centralized configuration management
Runtime Implementations: Platform-specific sandbox orchestration

Sandbox Lifecycle States

       create()
          |
          v
     +---------+
     | Pending |--------------------+
     +----+----+                    |
          |                         |
          | (provisioning)          |
          v                         |
     +---------+    pause()         |
     | Running |---------------+    |
     +----+----+               |    |
          |                    |    |
          |   resume()         |    |
          |   +--------------+ |    |
          |   |              | |    |
          |   v              | |    |
          | +--------+       | |    |
          +-| Paused |-------+ |    |
          | +----+---+         |    |
          |      |             |    |
          |      v             |    |
          |  +----------+      |    |
          |  | Resuming |------+    |
          |  +----------+           |
          |                         |
          | delete() or expire()    |
          v                         |
     +----------+                   |
     | Stopping |                   |
     +----+-----+                   |
          |                         |
          +----------------+--------+
          |                |
          v                v
     +------------+   +--------+
     | Terminated |   | Failed |
     +------------+   +--------+

Experimental Features

Optional experimental behavior; off by default. See release notes before production.

Auto-Renew on Access

Extends sandbox TTL when traffic is observed (lifecycle proxy and/or ingress + optional Redis queue). Per-sandbox: on create, set extensions["access.renew.extend.seconds"] (string integer 300-86400). Clients using the server proxy: request endpoints with use_server_proxy=true (REST) or SDK ConnectionConfig(..., use_server_proxy=True).

Development

Code Quality

bash

cd server
uv run ruff check        # Run linter
uv run ruff check --fix  # Auto-fix issues
uv run ruff format       # Format code

Testing

bash

cd server
uv run pytest                                                              # Run all tests
uv run pytest --cov=opensandbox_server --cov-report=term --cov-fail-under=80  # With coverage
uv run pytest tests/test_docker_service.py::test_create_sandbox_requires_entrypoint  # Specific test

License

This project is licensed under the terms specified in the LICENSE file in the repository root.

OpenSandbox Server ​

Features ​

Core capabilities ​

Extended capabilities ​

Requirements ​

Quick Start ​

Installation ​

Configuration ​

Run the server ​

API Documentation ​

API Authentication ​

Example Usage ​

Architecture ​

Component Responsibilities ​

Sandbox Lifecycle States ​

Experimental Features ​

Auto-Renew on Access ​

Development ​

Code Quality ​

Testing ​

License ​

OpenSandbox Server

Features

Core capabilities

Extended capabilities

Requirements

Quick Start

Installation

Configuration

Run the server

API Documentation

API Authentication

Example Usage

Architecture

Component Responsibilities

Sandbox Lifecycle States

Experimental Features

Auto-Renew on Access

Development

Code Quality

Testing

License