Sandbox SDK API Reference

Detailed API for @cloudflare/sandbox. For full docs: https://developers.cloudflare.com/sandbox/api/

Lifecycle

getSandbox(binding: DurableObjectNamespace<Sandbox>, sandboxId: string, options?: SandboxOptions): Sandbox

interface SandboxOptions {
  sleepAfter?: string;     // Duration before auto-sleep (default: "10m")
  keepAlive?: boolean;     // Prevent auto-sleep (default: false)
  normalizeId?: boolean;   // Lowercase IDs for preview URLs (default: false)
}

await sandbox.destroy(): Promise<void>  // Immediately terminate and delete all state

Commands

await sandbox.exec(command: string, options?: ExecOptions): Promise<ExecResult>

interface ExecOptions {
  cwd?: string;           // Working directory
  env?: Record<string, string>;  // Environment variables
  timeout?: number;       // Timeout in ms (no default; runs without timeout if unset)
  stdin?: string;         // Input to command
}

interface ExecResult {
  stdout: string;
  stderr: string;
  exitCode: number;
  success: boolean;       // exitCode === 0
}

Code Interpreter

await sandbox.createCodeContext(options?: CreateContextOptions): Promise<CodeContext>

interface CreateContextOptions {
  language?: 'python' | 'javascript' | 'typescript';  // default: 'python'
  cwd?: string;           // Working directory (default: '/workspace')
  envVars?: Record<string, string>;
  timeout?: number;       // Request timeout in ms (default: 30000)
}

await sandbox.runCode(code: string, options?: RunCodeOptions): Promise<ExecutionResult>

interface RunCodeOptions {
  context?: CodeContext;  // Reuse context for state persistence
  language?: 'python' | 'javascript' | 'typescript';
  timeout?: number;       // Execution timeout in ms (default: 60000)
}

interface ExecutionResult {
  code: string;
  logs: { stdout: string[]; stderr: string[] };
  results: RichOutput[];  // text, html, png, json, etc.
  error?: { name: string; value: string; traceback: string[] };
  executionCount: number;
}

Files

await sandbox.writeFile(path: string, content: string | Uint8Array): Promise<void>
await sandbox.readFile(path: string): Promise<{ content: string }>
await sandbox.mkdir(path: string, options?: { recursive?: boolean }): Promise<void>
await sandbox.listFiles(path: string): Promise<FileMetadata[]>
await sandbox.deleteFile(path: string): Promise<void>

interface FileMetadata {
  name: string;
  path: string;
  isDirectory: boolean;
  size: number;
  modifiedAt: string;
}

Ports

await sandbox.exposePort(port: number): Promise<{ url: string; token: string }>
await sandbox.unexposePort(port: number): Promise<void>
await sandbox.listPorts(): Promise<PortInfo[]>

Error Handling

Errors include context about the operation:

try {
  await sandbox.exec('invalid-command');
} catch (error) {
  // error.message includes command and sandbox context
}

For runCode(), check result.error instead of catching:

const result = await sandbox.runCode('1/0', { language: 'python' });
if (result.error) {
  console.error(result.error.name);  // "ZeroDivisionError"
}