JavaScript - Momentic

JavaScript Steps

JavaScript steps execute code as part of a test. async/await is supported. Return values are passed to downstream steps and must be JSON-serializable.

const res = await axios.post("https://api.example.com/login", {
  email: env.USERNAME,
  password: env.PASSWORD,
});

setVariable("SESSION_TOKEN", res.data.token);
return res.status;

Execution Contexts

Browser steps don’t have access to the Node sandbox globals. The browser context is available only for web tests. Mobile JavaScript runs in the Node sandbox.

Timeout

JavaScript steps default to a 90-second timeout. Configure per step via the Timeout field (seconds), or in simplified YAML (milliseconds):

- javascript:
    code: |
      const msg = await email.fetchLatest({
        inbox: "qa+signup", // your Momentic-provisioned inbox prefix
        timeout: 60_000,
      });
      return msg.text;
    timeout: 120000

The maximum configurable timeout is 10 minutes (600 seconds), suitable for long external polls or batched lookups against slow APIs. If a nested helper such as email.fetchLatest or sms.fetchLatest polls for longer than the JavaScript step’s own timeout, the step times out before the helper returns. Set the step’s Timeout to comfortably cover the longest nested poll.

{{ }} Templating

Any string input on any step can contain {{ expression }}. Expressions evaluate at runtime and are interpolated into the value.

- type:
    text: "{{ env.USERNAME }}@gmail.com"
    into: Email field

Don’t use {{}} inside JavaScript step source. Variables are already in scope as env.VARIABLE_NAME.

Momentic Utilities

The Momentic runtime provides these globals.

env

env is a read-only map of the current environment’s variables. See Variables for how variables are resolved.

const res = await axios.get("https://api.example.com/me", {
  headers: { Authorization: `Bearer ${env.API_TOKEN}` },
});

setVariable(name, value)

setVariable writes a variable scoped to the current test run. Downstream steps can read it via {{ env.NAME }} in a string input, or via env.NAME inside JavaScript.

const res = await axios.post("https://api.example.com/login", {
  email: env.USERNAME,
  password: env.PASSWORD,
});

setVariable("SESSION_TOKEN", res.data.token);

email

email sends and fetches email. See Email for inbox setup.

// fetch the latest verification email
const msg = await email.fetchLatest({
  inbox: "qa+signup", // your Momentic-provisioned inbox prefix
  timeout: 30_000,
});
const [code] = msg.text.match(/\b\d{6}\b/) ?? [];
if (!code) throw new Error("No verification code found in email");
setVariable("VERIFICATION_CODE", code);

sms

sms sends and fetches SMS. See SMS for number setup.

const msg = await sms.fetchLatest({
  to: "+15551234567",
  timeout: 60_000,
});
const [code] = msg.body.match(/\b\d{6}\b/) ?? [];
if (!code) throw new Error("No OTP code found in SMS");
setVariable("OTP", code);

extractCookiesFromResponse(response)

extractCookiesFromResponse converts a fetch / axios response’s Set-Cookie headers into cookie objects for a browser context. Use it to bootstrap an authenticated session.

const res = await fetch("https://api.example.com/login", {
  method: "POST",
  body: JSON.stringify({ email: env.USERNAME, password: env.PASSWORD }),
});

const cookies = await extractCookiesFromResponse(res);
setVariable("AUTH_COOKIES", cookies);

mock

mock is only available in mock handler steps on mocked routes. It exposes the intercepted Request and the upstream Response.

// stub the /pricing response but forward everything else
if (mock.request.url.endsWith("/pricing")) {
  return new Response(JSON.stringify({ plan: "enterprise" }), {
    status: 200,
    headers: { "content-type": "application/json" },
  });
}
return mock.response;

Libraries

axios

axios is an HTTP client. See axios docs.

const { data } = await axios.get("https://api.example.com/status");
assert.equal(data.ok, true);

assert

assert provides Node’s built-in assertions. See Node docs.

assert.equal(res.status, 200);
assert.deepStrictEqual(res.data, { success: true });

faker

faker generates realistic fake data. See Faker docs.

const email = faker.internet.email();
const name = faker.person.fullName();
setVariable("NEW_USER_EMAIL", email);
setVariable("NEW_USER_NAME", name);

moment

moment parses and formats dates. See Moment docs.

// pick a date 30 days from now, formatted for a date input
setVariable("FUTURE_DATE", moment().add(30, "days").format("YYYY-MM-DD"));

pg

pg is a Postgres client. See node-postgres docs.

const client = new pg.Client({ connectionString: env.DATABASE_URL });
await client.connect();
const { rows } = await client.query(
  "SELECT id FROM users WHERE email = $1 LIMIT 1",
  [env.TEST_EMAIL],
);
await client.end();
setVariable("USER_ID", rows[0].id);

OTPAuth

OTPAuth generates time-based one-time password (TOTP) codes for two-factor authentication (2FA) tests. See otpauth docs.

const totp = new OTPAuth.TOTP({ secret: env.TOTP_SECRET });
setVariable("OTP_CODE", totp.generate());

child_process

child_process spawns subprocesses. See Node docs.

const { execSync } = child_process;
const branch = execSync("git rev-parse --abbrev-ref HEAD").toString().trim();
setVariable("GIT_BRANCH", branch);

Octokit + createAppAuth

Octokit with createAppAuth provides authenticated GitHub API access. See Octokit docs and auth-app docs.

const octokit = new Octokit({
  authStrategy: createAppAuth,
  auth: {
    appId: env.GITHUB_APP_ID,
    privateKey: env.GITHUB_APP_PRIVATE_KEY,
    installationId: env.GITHUB_INSTALLATION_ID,
  },
});

const { data: pr } = await octokit.rest.pulls.get({
  owner: "momentic-ai",
  repo: "examples",
  pull_number: 42,
});
setVariable("PR_STATE", pr.state);