[Feature] Allow reconnecting to page in a separate processes

[jperl]

Use Case: I need to connect to an existing page created in another process to create an end-to-end test.

The way I do this right now is by using launchServer in the first process and sending the wsEndpoint and page._delegate._targetId to the second process. Then I create a WebSocket manually in the second process that uses Target.attachToTarget to connect to the page.

Feature Request:

1. Expose page.targetId()
2. Allow passing targetId to browser.newBrowserCDPSession(targetId?: string);

Proposed Usage:

Process A.

const server = await playwright.chromium.launchServer();

const browser = await playwright.chromium.connect({
  wsEndpoint: server.wsEndpoint(),
});

const context = await browser.newContext();
const page = await context.newPage();

sendToProcessB({ 
  targetId: page.targetId(),
  wsEndpoint,
})

Process B.

const { targetId, wsEndpoint } = receiveFromProcessA();

const browser = await playwright.chromium.connect({ wsEndpoint });

const session = await browser.newBrowserCDPSession(targetId);

[jperl]

Alternative approach:

It would be great if browsers connected to the same browser server were attached to the same contexts and pages.

const server = await playwright.chromium.launchServer();

const browserA = await playwright.chromium.connect({
  wsEndpoint: server.wsEndpoint(),
});
const contextA = await browser.newContext();
const pageA = await contextOne.newPage();

const browserTwo = await playwright.chromium.connect({
  wsEndpoint: server.wsEndpoint(),
});

// same as contextA
const contextB = browserTwo.contexts()[0];

// same as pageA
const pageB = contextB.pages()[0];

[pavelfeldman]

Hm! We were explicitly isolating the contexts, but I don't think we were thinking about your use case. Could you share why you need to reuse context from multiple places in your end2end test?

[jperl]

This is definitely an edge-case, but it is an end-to-end test for npx qawolf create.

So I need to simulate browser actions in a spawned child process and check it generates code.

[kababoom]

New to playwright, thank you for your time and effort creating this......

I'm also looking for a way to reconnect to a previously created session to cover my end-to-end testcases.

• StartServer.js
• Openpage.js page.goto-> evaluate element -> fill username/password -> take screenshot
• Login.js click button -> check for element -> take screenshot.js
  etc...

So Login.js should continue with previously created Openpage.js session.

This would be the only way to integrate playwrite inside our existing framework and I'm not able to get this to work (yet).

[pavelfeldman]

@kababoom I think you are talking about #1745. I'm closing the session reconnect aspect for now.