Network and APIs

Mock requests, listen to traffic, test APIs, reuse logged-in sessions.

Network and APIs

Control what the browser sends and receives: mock or block requests, watch traffic, call HTTP APIs without a browser, and log in once for many tests.

playwright().browse( ( page ) => {
	page.intercept( "**/api/users" ).respondJson( [ "Luis", "Brad" ] )
	page.visit( "http://localhost:8080/users" ).assertSee( "Brad" )
} )

Mock and block requests

Register an intercept before the request happens, usually before visit():

page.intercept( "**/api/users" ).respondJson( [ "Luis", "Brad" ] )
page.intercept( "**/api/fail" ).respond( 500, "Boom" )
page.intercept( "**/*.{png,jpg}" ).abort()
page.intercept( "**/api/**" ).resume( { headers : { "X-Test" : "1" } } )
page.intercept( "**/api/**" ).handle( ( route ) => route.fallback() )

• Patterns are globs, full URLs or page.regex().
• respondJson( data, status, headers ) and respond( status, body, headers ) answer the request; abort() blocks it; resume( overrides ) lets it through, optionally changing url, method, headers or postData.
• handle() receives Playwright's Route for anything else: fulfill(), abort(), resume(), fallback(), request().
• context.intercept() applies to every page of a context.

Listen

page.onConsole( ( message ) => println( message.type & ": " & message.text ) )
	.onRequest( ( sent ) => println( sent.method & " " & sent.url ) )
	.onResponse( ( received ) => println( received.status & " " & received.url ) )
	.onPageError( ( error ) => println( error.message ) )
	.onDialog( ( dialog ) => dialog.accept() )

API testing

api = playwright().request( { baseURL : "http://localhost:8080" } )
try {
	login = api.post( "/api/login", { json : { user : "luis" }, headers : { "X-Token" : "abc" } } )
	api.expect( login ).toBeOK()

	users = api.get( "/api/users", { params : { page : 2 } } ).json()
} finally {
	api.close()
}

• Methods: get(), post(), put(), patch(), delete().
• Options: json, form, data, params, headers, timeout, failOnStatusCode, maxRedirects.
• Responses have status(), ok(), url(), headers(), text() and json().
• context.request() shares the cookies of a browser context: log in through the API, then browse.

Cookies, permissions and offline

The context of a page holds its cookies and browser state:

context = page.context()
context.addCookies( [ { name : "consent", value : "yes", url : "http://localhost:8080" } ] )
context.grantPermissions( [ "geolocation", "clipboard-read" ] )
context.setOffline( true )
println( context.cookies() )

Also clearCookies() and saveStorageState( path ).

Saved sessions

Log in once, reuse the cookies and local storage everywhere:

pw = playwright( { baseURL : "http://localhost:8080" } )

pw.session( "admin", ( page ) => {
	page.visit( "/login" )
		.fill( "Email", "admin@site.com" )
		.fill( "Password", "secret" )
		.click( "Sign in" )
		.assertPathIs( "/dashboard" )
}, { maxAge : 720 } )

pw.browse( ( page ) => {
	page.visit( "/admin" ).assertSee( "Dashboard" )
}, { session : "admin" } )

• The setup runs only when the session is missing, older than maxAge minutes (0, the default, never expires) or refresh : true is passed. context passes context overrides to the setup page.
• Use a session with { session : "admin" } in browse(), newPage(), newContext(), playwright() or a profile.
• The setup page always starts clean, even on a manager configured with session.
• Sessions are stored in {home}/sessions, outside your project, because they hold cookies.