How do you test an authenticated app without logging in every test?

Logging in through the UI for every test is slow and makes every test depend on the login page. The standard Playwright pattern is a setup project that authenticates once, writes the storage state to a file, and has the real test projects depend on it.

import { test as setup, expect } from "@playwright/test";

setup("authenticate", async ({ page }) => {
  await page.goto("/login");
  await page.getByLabel("Email").fill("asha@example.com");
  await page.getByLabel("Password").fill("correct-horse");
  await page.getByRole("button", { name: "Sign in" }).click();

  await expect(page.getByRole("heading", { name: "Dashboard" })).toBeVisible();
  await page.context().storageState({ path: "playwright/.auth/user.json" });
});

projects: [
  { name: "setup", testMatch: "**/auth.setup.ts" },
  {
    name: "chromium",
    use: {
      ...devices["Desktop Chrome"],
      storageState: "playwright/.auth/user.json",
    },
    dependencies: ["setup"],
  },
],

Practical points

• Authenticate through the UI when login itself is under test, or through an API when speed matters more
• Storage state contains cookies and localStorage, so treat the file as a secret
• Use separate state files for different roles such as admin and customer
• Re-run setup when the session expires or the auth flow changes
• Do not rely on one logged-in state for tests that specifically verify login or logout

For an API-first login, call the auth endpoint with the request fixture, then write the returned cookies or token into a context. That is faster than driving the form and less coupled to the login page markup, as long as the session format matches what the browser expects.