The login window can route through a configurable egress proxy - #279
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Some sites reject a login when it arrives from a datacenter IP. Give the browser login window an optional HTTP proxy so the login step can egress from a different IP. Only the login window uses it — borrows keep the box IP, which is enough once a session is minted. The proxy is an authless address authored as sandbox.browser_login_proxy; what sits behind it is deploy config, so no proxy secret enters the app. login.py injects it into the launcher's environment; session-launch passes it to Playwright and, with a proxy set, blocks the WebRTC UDP leak. Empty keeps the box IP.
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Some sites reject a login when it arrives from a datacenter IP. This gives the browser login window an optional HTTP proxy so the login step can egress from a different IP.
Only the login window uses it. A session keeps working when later used from the box's own IP, so only the login step needs the proxy — borrows are unchanged.
Change
settings.py—Sandbox.browser_login_proxy, authored assandbox.browser_login_proxyin the config file.setup_env.py— added to_KNOWN_TOML_KEYS["sandbox"]and the default template, so setup accepts it (a[sandbox]key not in the known set is otherwise treated as a provider table).browser/login.py— injects the proxy into thesession-launchenvironment, only when set and shell-quoted. The borrow launcher insessions.pyis untouched.deploy/browser/session-launch— reads it, passes Playwright'sproxy: { server }, and blocks the WebRTC UDP leak when a proxy is set.The value is an authless address (e.g.
http://172.17.0.1:8888); what sits behind it is deploy config, so no proxy secret enters the app. Empty keeps today's behavior. A fixed proxy fails closed: an unreachable exit errors the login browser rather than falling back to the box IP.Verification
Built the browser image and confirmed on a running container: with the proxy set, the browser launches with
--proxy-serverand its egress IP is the proxy's; unset, no proxy flag and egress is the box IP. Unit tests cover the login command — proxy injected when set, omitted when unset, and shell-quoted so a bad value can't inject.