Playwright · Senior · Question 18 of 77

How do you mock a WebSocket server in a Playwright test?

1Use page.route() with fulfill for the ws:// URL
2Use page.routeWebSocket() to intercept and answer messages
3WebSockets can't be mocked, only observed in traces

Show the answer

Correct answer: Use page.routeWebSocket() to intercept and answer messages

Explanation

routeWebSocket can act as the server or sit between the page and the real server to change messages.

Further reading

Playwright: Network ↗

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