hello-theme/tests/playwright/wp-authentication.ts

import {
	APIRequest,
	APIRequestContext,
	Page,
	chromium,
	APIResponse,
} from '@playwright/test';

export async function login(
	apiRequest: APIRequest,
	user: string,
	password: string,
	baseUrl: string,
) {
	// Important: make sure we authenticate in a clean environment by unsetting storage state.
	const context = await apiRequest.newContext({ storageState: undefined });

	await context.post(`${baseUrl}/wp-login.php`, {
		form: {
			log: user,
			pwd: password,
			'wp-submit': 'Log In',
			redirect_to: `${baseUrl}/wp-admin/`,
			testcookie: '1',
		},
	});
	return context;
}

export async function fetchNonce(context: APIRequestContext, baseUrl: string) {
	const response = await context.get(`${baseUrl}/wp-admin/post-new.php`);

	await validateResponse(response, 'Failed to fetch page');

	let pageText = await response.text();
	if (pageText.includes('WordPress has been updated!')) {
		pageText = await updateDatabase(context, baseUrl);
	}

	const nonceMatch = pageText.match(/var wpApiSettings = .*;/);
	if (!nonceMatch) {
		throw new Error(`Nonce not found on the page:\n"${pageText}"`);
	}

	return nonceMatch[0].replace(/^.*"nonce":"([^"]*)".*$/, '$1');
}

async function updateDatabase(
	context: APIRequestContext,
	baseUrl: string,
): Promise<string> {
	const browser = await chromium.launch();
	const browserContext = await browser.newContext();
	const page: Page = await browserContext.newPage();
	await page.goto(`${baseUrl}/wp-admin/post-new.php`);
	await page.getByText('Update WordPress Database').click();
	await page.getByText('Continue').click();

	const retryResponse = await context.get(`${baseUrl}/wp-admin/post-new.php`);

	const pageText = await retryResponse.text();
	await browser.close();
	return pageText;
}

async function validateResponse(response: APIResponse, errorMessage: string) {
	if (!response.ok()) {
		throw new Error(`
            ${errorMessage}: ${response.status}.
            ${await response.text()}
            ${response.url()}
        `);
	}
}