fix workspace bug

.changeset/sixty-walls-serve.md

@@ -0,0 +1,5 @@
+---
+"@cloudflare/sandbox": patch
+---
+
+fix workspace bug

packages/sandbox-container/src/session.ts

@@ -25,7 +25,7 @@
 
 import { randomUUID } from 'node:crypto';
 import { watch } from 'node:fs';
-import { mkdir, rm } from 'node:fs/promises';
+import { mkdir, rm, stat } from 'node:fs/promises';
 import { tmpdir } from 'node:os';
 import { basename, dirname, join } from 'node:path';
 import type { ExecEvent, Logger } from '@repo/shared';
@@ -46,7 +46,14 @@ export interface SessionOptions {
   /** Session identifier (generated if not provided) */
   id: string;
 
-  /** Working directory for the session */
+  /**
+   * Initial working directory for the shell.
+   *
+   * Note: This only affects where the shell starts. Individual commands can
+   * specify their own cwd via exec options, and the shell can cd anywhere.
+   * If the specified directory doesn't exist when the session initializes,
+   * the session will fall back to the home directory.
+   */
   cwd?: string;
 
   /** Environment variables for the session */
@@ -137,10 +144,28 @@ export class Session {
     this.sessionDir = join(tmpdir(), `session-${this.id}-${Date.now()}`);
     await mkdir(this.sessionDir, { recursive: true });
 
+    // Determine working directory. If the requested cwd doesn't exist, we fall
+    // back to the home directory since it's a natural default for shell sessions.
+    const homeDir = process.env.HOME || '/root';
+    let cwd = this.options.cwd || CONFIG.DEFAULT_CWD;
+    try {
+      await stat(cwd);
+    } catch {
+      this.logger.debug(
+        `Shell startup directory '${cwd}' does not exist, using '${homeDir}'`,
+        {
+          sessionId: this.id,
+          requestedCwd: cwd,
+          actualCwd: homeDir
+        }
+      );
+      cwd = homeDir;
+    }
+
     // Spawn persistent bash with stdin pipe - no IPC or wrapper needed!
     this.shell = Bun.spawn({
       cmd: ['bash', '--norc'],
-      cwd: this.options.cwd || CONFIG.DEFAULT_CWD,
+      cwd,
       env: {
         ...process.env,
         ...this.options.env,

packages/sandbox-container/tests/session.test.ts

@@ -75,6 +75,53 @@ describe('Session', () => {
       // Session directory should be created (we can't easily check without accessing private fields)
       expect(session.isReady()).toBe(true);
     });
+
+    it('should fall back to home directory when cwd does not exist (issue #288)', async () => {
+      // Session cwd only affects shell startup directory - it's not critical.
+      // If cwd doesn't exist, we fall back to the home directory since individual
+      // commands can specify their own cwd anyway.
+      session = new Session({
+        id: 'test-session-nonexistent-cwd',
+        cwd: '/nonexistent/path/that/does/not/exist'
+      });
+
+      await session.initialize();
+
+      expect(session.isReady()).toBe(true);
+
+      // Verify we can execute commands
+      const result = await session.exec('pwd');
+      expect(result.exitCode).toBe(0);
+      // The shell should have started in the home directory since the requested cwd doesn't exist
+      const homeDir = process.env.HOME || '/root';
+      expect(result.stdout.trim()).toBe(homeDir);
+    });
+
+    it('should fall back to home directory when workspace is deleted before session creation (issue #288)', async () => {
+      // Simulate the exact scenario from issue #288
+      // Create a workspace, then delete it, then try to create a session with it
+      const workspaceDir = join(testDir, 'workspace');
+      await mkdir(workspaceDir, { recursive: true });
+
+      // Delete the workspace
+      await rm(workspaceDir, { recursive: true, force: true });
+
+      // Now try to create a session with the deleted workspace as cwd
+      session = new Session({
+        id: 'test-session-deleted-workspace',
+        cwd: workspaceDir
+      });
+
+      // Should succeed - falls back to home directory
+      await session.initialize();
+
+      expect(session.isReady()).toBe(true);
+
+      // Verify we can execute commands
+      const result = await session.exec('echo "session works"');
+      expect(result.exitCode).toBe(0);
+      expect(result.stdout.trim()).toBe('session works');
+    });
   });
 
   describe('exec', () => {
@@ -496,6 +543,92 @@ describe('Session', () => {
       expect(result.exitCode).toBe(1);
       expect(result.stderr).toContain('Failed to change directory');
     });
+
+    it('should continue working after session cwd is deleted (issue #288)', async () => {
+      // Create a working directory for the session
+      const workspaceDir = join(testDir, 'workspace');
+      await mkdir(workspaceDir, { recursive: true });
+
+      session = new Session({
+        id: 'test-cwd-deletion',
+        cwd: workspaceDir
+      });
+
+      await session.initialize();
+
+      // Verify baseline works
+      const baseline = await session.exec('echo "baseline"');
+      expect(baseline.exitCode).toBe(0);
+      expect(baseline.stdout.trim()).toBe('baseline');
+
+      // Delete the workspace directory (this is the bug scenario)
+      await session.exec(`rm -rf ${workspaceDir}`);
+
+      // Try a subsequent command - this should NOT fail with an obscure error
+      // It should either work (falling back to /) or give a clear error message
+      const afterRemoval = await session.exec('echo "after removal"');
+
+      // The command should succeed - bash can still run commands even if cwd is deleted
+      // It will use the deleted directory's inode until a cd happens
+      expect(afterRemoval.exitCode).toBe(0);
+      expect(afterRemoval.stdout.trim()).toBe('after removal');
+    });
+
+    it('should handle cwd being replaced with symlink (issue #288)', async () => {
+      // Create directories for the test
+      const workspaceDir = join(testDir, 'workspace');
+      const backupDir = join(testDir, 'backup');
+      await mkdir(workspaceDir, { recursive: true });
+      await mkdir(backupDir, { recursive: true });
+
+      session = new Session({
+        id: 'test-cwd-symlink',
+        cwd: workspaceDir
+      });
+
+      await session.initialize();
+
+      // Verify baseline works
+      const baseline = await session.exec('echo "baseline"');
+      expect(baseline.exitCode).toBe(0);
+      expect(baseline.stdout.trim()).toBe('baseline');
+
+      // Replace workspace with a symlink to backup directory
+      await session.exec(
+        `rm -rf ${workspaceDir} && ln -sf ${backupDir} ${workspaceDir}`
+      );
+
+      // Try a subsequent command - should continue working
+      const afterSymlink = await session.exec('echo "after symlink"');
+      expect(afterSymlink.exitCode).toBe(0);
+      expect(afterSymlink.stdout.trim()).toBe('after symlink');
+    });
+
+    it('should be recoverable by cd-ing to valid directory after cwd deletion', async () => {
+      // Create a working directory for the session
+      const workspaceDir = join(testDir, 'workspace');
+      await mkdir(workspaceDir, { recursive: true });
+
+      session = new Session({
+        id: 'test-cwd-recovery',
+        cwd: workspaceDir
+      });
+
+      await session.initialize();
+
+      // Delete the workspace directory
+      await session.exec(`rm -rf ${workspaceDir}`);
+
+      // Change to a valid directory - this should work and recover the session
+      const cdResult = await session.exec('cd /tmp && pwd');
+      expect(cdResult.exitCode).toBe(0);
+      expect(cdResult.stdout.trim()).toBe('/tmp');
+
+      // Subsequent commands should work
+      const afterCd = await session.exec('echo "recovered"');
+      expect(afterCd.exitCode).toBe(0);
+      expect(afterCd.stdout.trim()).toBe('recovered');
+    });
   });
 
   describe('FIFO cleanup', () => {

tests/e2e/workspace-deletion-workflow.test.ts

@@ -0,0 +1,105 @@
+/**
+ * Workspace Deletion Workflow Tests (Issue #288)
+ *
+ * Tests that new sessions fall back to the home directory when /workspace
+ * doesn't exist, preventing "Unknown Error, TODO" failures.
+ *
+ * @see https://github.com/cloudflare/sandbox-sdk/issues/288
+ */
+
+import { describe, test, expect, beforeAll } from 'vitest';
+import {
+  getSharedSandbox,
+  createUniqueSession
+} from './helpers/global-sandbox';
+import type { ExecResult } from '@repo/shared';
+
+describe('Workspace Deletion Workflow (Issue #288)', () => {
+  let workerUrl: string;
+  let sandbox: Awaited<ReturnType<typeof getSharedSandbox>>;
+
+  beforeAll(async () => {
+    sandbox = await getSharedSandbox();
+    workerUrl = sandbox.workerUrl;
+  }, 120000);
+
+  /**
+   * Core test for issue #288: new session creation after /workspace is deleted.
+   *
+   * The bug was that creating a NEW session after /workspace was deleted would
+   * fail with "Unknown Error, TODO". The fix makes session initialization fall
+   * back to the home directory if /workspace doesn't exist.
+   */
+  test('new session falls back to home directory when /workspace is deleted', async () => {
+    const setupHeaders = sandbox.createHeaders(createUniqueSession());
+
+    // Delete /workspace
+    const deleteResponse = await fetch(`${workerUrl}/api/execute`, {
+      method: 'POST',
+      headers: setupHeaders,
+      body: JSON.stringify({ command: 'rm -rf /workspace' })
+    });
+    expect(deleteResponse.status).toBe(200);
+
+    // Create a NEW session - this is where the bug occurred
+    const newHeaders = sandbox.createHeaders(createUniqueSession());
+
+    const execResponse = await fetch(`${workerUrl}/api/execute`, {
+      method: 'POST',
+      headers: newHeaders,
+      body: JSON.stringify({ command: 'pwd' })
+    });
+
+    expect(execResponse.status).toBe(200);
+    const execData = (await execResponse.json()) as ExecResult;
+    expect(execData.success).toBe(true);
+    expect(execData.stdout?.trim()).toBe('/root');
+
+    // Restore /workspace for other tests
+    await fetch(`${workerUrl}/api/execute`, {
+      method: 'POST',
+      headers: setupHeaders,
+      body: JSON.stringify({ command: 'mkdir -p /workspace' })
+    });
+  }, 90000);
+
+  /**
+   * Tests that new sessions work when /workspace is a symlink to a valid directory.
+   */
+  test('new session works when /workspace is a symlink', async () => {
+    const setupHeaders = sandbox.createHeaders(createUniqueSession());
+    const backupDir = `/tmp/workspace-backup-${Date.now()}`;
+
+    // Replace /workspace with a symlink
+    await fetch(`${workerUrl}/api/execute`, {
+      method: 'POST',
+      headers: setupHeaders,
+      body: JSON.stringify({
+        command: `mkdir -p ${backupDir} && rm -rf /workspace && ln -sf ${backupDir} /workspace`
+      })
+    });
+
+    // Create a NEW session - should work with the symlink
+    const newHeaders = sandbox.createHeaders(createUniqueSession());
+
+    const execResponse = await fetch(`${workerUrl}/api/execute`, {
+      method: 'POST',
+      headers: newHeaders,
+      body: JSON.stringify({ command: 'pwd -P' }) // -P resolves symlinks
+    });
+
+    expect(execResponse.status).toBe(200);
+    const execData = (await execResponse.json()) as ExecResult;
+    expect(execData.success).toBe(true);
+    expect(execData.stdout?.trim()).toBe(backupDir);
+
+    // Restore /workspace as a real directory
+    await fetch(`${workerUrl}/api/execute`, {
+      method: 'POST',
+      headers: setupHeaders,
+      body: JSON.stringify({
+        command: `rm -f /workspace && mkdir -p /workspace && rm -rf ${backupDir}`
+      })
+    });
+  }, 90000);
+});