Add modal sandbox support (#192)

* add modal sandbox example

* add test instructions

---------

Co-authored-by: Nathan Flurry <NathanFlurry@users.noreply.github.com>

examples/modal/package.json

@@ -0,0 +1,20 @@
+{
+  "name": "@sandbox-agent/example-modal",
+  "private": true,
+  "type": "module",
+  "scripts": {
+    "start": "tsx src/modal.ts",
+    "typecheck": "tsc --noEmit"
+  },
+  "dependencies": {
+    "modal": "latest",
+    "@sandbox-agent/example-shared": "workspace:*",
+    "sandbox-agent": "workspace:*"
+  },
+  "devDependencies": {
+    "@types/node": "latest",
+    "tsx": "latest",
+    "typescript": "latest",
+    "vitest": "^3.0.0"
+  }
+}

examples/modal/src/modal.ts

@@ -0,0 +1,123 @@
+import { ModalClient } from "modal";
+import { SandboxAgent } from "sandbox-agent";
+import { detectAgent, buildInspectorUrl, waitForHealth } from "@sandbox-agent/example-shared";
+import { fileURLToPath } from "node:url";
+import { resolve } from "node:path";
+import { run } from "node:test";
+
+const PORT = 3000;
+const APP_NAME = "sandbox-agent";
+
+async function buildSecrets(modal: ModalClient) {
+  const envVars: Record<string, string> = {};
+  if (process.env.ANTHROPIC_API_KEY) 
+    envVars.ANTHROPIC_API_KEY = process.env.ANTHROPIC_API_KEY;
+  if (process.env.OPENAI_API_KEY) 
+    envVars.OPENAI_API_KEY = process.env.OPENAI_API_KEY;
+
+  if (Object.keys(envVars).length === 0) return [];
+  return [await modal.secrets.fromObject(envVars)];
+}
+
+export async function setupModalSandboxAgent(): Promise<{
+  baseUrl: string;
+  cleanup: () => Promise<void>;
+}> {
+  const modal = new ModalClient();
+  const app = await modal.apps.fromName(APP_NAME, { createIfMissing: true });
+
+  const image = modal.images
+    .fromRegistry("ubuntu:22.04")
+    .dockerfileCommands([
+      "RUN apt-get update && apt-get install -y curl ca-certificates",
+      "RUN curl -fsSL https://releases.rivet.dev/sandbox-agent/0.2.x/install.sh | sh",
+    ]);
+
+  const secrets = await buildSecrets(modal);
+
+  console.log("Creating Modal sandbox!");
+  const sb = await modal.sandboxes.create(app, image, {
+    secrets: secrets, 
+    encryptedPorts: [PORT],
+  });
+  console.log(`Sandbox created: ${sb.sandboxId}`);
+
+  const exec = async (cmd: string) => {
+    const p = await sb.exec(["bash", "-c", cmd], {
+      stdout: "pipe",
+      stderr: "pipe",
+    });
+    const exitCode = await p.wait();
+    if (exitCode !== 0) {
+      const stderr = await p.stderr.readText();
+      throw new Error(`Command failed (exit ${exitCode}): ${cmd}\n${stderr}`);
+    }
+  };
+
+  if (process.env.ANTHROPIC_API_KEY) {
+    console.log("Installing Claude agent...");
+    await exec("sandbox-agent install-agent claude");
+  }
+  if (process.env.OPENAI_API_KEY) {
+    console.log("Installing Codex agent...");
+    await exec("sandbox-agent install-agent codex");
+  }
+
+  console.log("Starting server...");
+
+  await sb.exec(
+    ["bash", "-c", `sandbox-agent server --no-token --host 0.0.0.0 --port ${PORT} &`],
+  );
+
+  const tunnels = await sb.tunnels();
+  const tunnel = tunnels[PORT];
+  if (!tunnel) {
+    throw new Error(`No tunnel found for port ${PORT}`);
+  }
+  const baseUrl = tunnel.url;
+
+  console.log("Waiting for server...");
+  await waitForHealth({ baseUrl });
+
+  const cleanup = async () => {
+    try {
+      await sb.terminate();
+    } catch (error) {
+      console.warn("Cleanup failed:", error instanceof Error ? error.message : error);
+    }
+  };
+
+  return { baseUrl, cleanup };
+}
+
+export async function runModalExample(): Promise<void> {
+  const { baseUrl, cleanup } = await setupModalSandboxAgent();
+
+  const handleExit = async () => {
+    await cleanup();
+    process.exit(0);
+  };
+
+  process.once("SIGINT", handleExit);
+  process.once("SIGTERM", handleExit);
+
+  const client = await SandboxAgent.connect({ baseUrl });
+  const session = await client.createSession({ agent: detectAgent(), sessionInit: { cwd: "/root", mcpServers: [] } });
+  const sessionId = session.id;
+
+  console.log(`  UI: ${buildInspectorUrl({ baseUrl, sessionId })}`);
+  console.log("  Press Ctrl+C to stop.");
+
+  await new Promise(() => {});
+}
+
+const isDirectRun = Boolean(
+  process.argv[1] && resolve(process.argv[1]) === fileURLToPath(import.meta.url),
+);
+
+if (isDirectRun) {
+  runModalExample().catch((error) => {
+    console.error(error instanceof Error ? error.message : error);
+    process.exit(1);
+  });
+}

examples/modal/tests/modal.test.ts

@@ -0,0 +1,28 @@
+import { describe, it, expect } from "vitest";
+import { buildHeaders } from "@sandbox-agent/example-shared";
+import { setupModalSandboxAgent } from "../src/modal.ts";
+
+const shouldRun = Boolean(process.env.MODAL_TOKEN_ID && process.env.MODAL_TOKEN_SECRET);
+const timeoutMs = Number.parseInt(process.env.SANDBOX_TEST_TIMEOUT_MS || "", 10) || 300_000;
+
+const testFn = shouldRun ? it : it.skip;
+
+describe("modal example", () => {
+  testFn(
+    "starts sandbox-agent and responds to /v1/health",
+    async () => {
+      const { baseUrl, cleanup } = await setupModalSandboxAgent();
+      try {
+        const response = await fetch(`${baseUrl}/v1/health`, {
+          headers: buildHeaders({}),
+        });
+        expect(response.ok).toBe(true);
+        const data = await response.json();
+        expect(data.status).toBe("ok");
+      } finally {
+        await cleanup();
+      }
+    },
+    timeoutMs,
+  );
+});

examples/modal/tsconfig.json

@@ -0,0 +1,16 @@
+{
+  "compilerOptions": {
+    "target": "ES2022",
+    "lib": ["ES2022", "DOM"],
+    "module": "ESNext",
+    "moduleResolution": "Bundler",
+    "allowImportingTsExtensions": true,
+    "noEmit": true,
+    "esModuleInterop": true,
+    "strict": true,
+    "skipLibCheck": true,
+    "resolveJsonModule": true
+  },
+  "include": ["src/**/*"],
+  "exclude": ["node_modules", "**/*.test.ts"]
+}