Note: bug fixed Nov 2022

GitHub Codespaces port forwarding bugs / limitations

• Websocket Connectivity fails for 1-5 minutes at startup due to improper Origin header on forwarded requests
• /auth namespace appears reserved for internal use at startup
• Max ~4 minute Websocket connection duration https://github.com/TrueBrain/codespaces-websocket

Reproduction steps

• Create a new Codespace from this repo, using the latest VS Code Desktop or Web
• Run python server.py
• Open the URL it prints
  • The behavior doesn't seem to change if the port is public or private
• Observe the connectivity log in the web app
• Observe the connectivity log in terminal, notice the difference between the Origin header in the request received by the application over time

Example

Web connectivity log

Attempting to connect to websocket every 10s and send a ping every 30s ....

Thu Sep 22 2022 10:44:13 GMT-0500 (CDT) => Connecting to wss://jnewland-codespaces-websockets-bug-697p9g29wq-3000.githubpreview.dev/ws ...
Thu Sep 22 2022 10:44:14 GMT-0500 (CDT) => Connection failed! 0.63 seconds since page load.
Thu Sep 22 2022 10:44:24 GMT-0500 (CDT) => Connecting to wss://jnewland-codespaces-websockets-bug-697p9g29wq-3000.githubpreview.dev/ws ...
Thu Sep 22 2022 10:44:24 GMT-0500 (CDT) => Connection failed! 11.05 seconds since page load.
Thu Sep 22 2022 10:44:34 GMT-0500 (CDT) => Connecting to wss://jnewland-codespaces-websockets-bug-697p9g29wq-3000.githubpreview.dev/ws ...
Thu Sep 22 2022 10:44:35 GMT-0500 (CDT) => Connection failed! 21.48 seconds since page load.
Thu Sep 22 2022 10:44:45 GMT-0500 (CDT) => Connecting to wss://jnewland-codespaces-websockets-bug-697p9g29wq-3000.githubpreview.dev/ws ...
Thu Sep 22 2022 10:44:45 GMT-0500 (CDT) => Connection failed! 32.14 seconds since page load.
Thu Sep 22 2022 10:44:55 GMT-0500 (CDT) => Connecting to wss://jnewland-codespaces-websockets-bug-697p9g29wq-3000.githubpreview.dev/ws ...
Thu Sep 22 2022 10:44:56 GMT-0500 (CDT) => Connection failed! 42.78 seconds since page load.
Thu Sep 22 2022 10:45:06 GMT-0500 (CDT) => Connecting to wss://jnewland-codespaces-websockets-bug-697p9g29wq-3000.githubpreview.dev/ws ...
Thu Sep 22 2022 10:45:07 GMT-0500 (CDT) => Connection failed! 53.27 seconds since page load.
Thu Sep 22 2022 10:45:17 GMT-0500 (CDT) => Connecting to wss://jnewland-codespaces-websockets-bug-697p9g29wq-3000.githubpreview.dev/ws ...
Thu Sep 22 2022 10:45:17 GMT-0500 (CDT) => Connection failed! 63.66 seconds since page load.
Thu Sep 22 2022 10:45:27 GMT-0500 (CDT) => Connecting to wss://jnewland-codespaces-websockets-bug-697p9g29wq-3000.githubpreview.dev/ws ...
Thu Sep 22 2022 10:45:27 GMT-0500 (CDT) => Connection failed! 74.14 seconds since page load.
Thu Sep 22 2022 10:45:37 GMT-0500 (CDT) => Connecting to wss://jnewland-codespaces-websockets-bug-697p9g29wq-3000.githubpreview.dev/ws ...
Thu Sep 22 2022 10:45:38 GMT-0500 (CDT) => Connection failed! 84.80 seconds since page load.
Thu Sep 22 2022 10:45:48 GMT-0500 (CDT) => Connecting to wss://jnewland-codespaces-websockets-bug-697p9g29wq-3000.githubpreview.dev/ws ...
Thu Sep 22 2022 10:45:49 GMT-0500 (CDT) => Connected 95.37 seconds after page load.
Thu Sep 22 2022 10:45:49 GMT-0500 (CDT) => pong in 126ms.
Thu Sep 22 2022 10:46:19 GMT-0500 (CDT) => pong in 128ms.

Server request log

2022-09-22 15:44:13,750 <Request GET / > <Response OK eof> 0.00s
2022-09-22 15:44:14,332 <Request GET /ws > Origin=http://localhost
2022-09-22 15:44:14,332 <Request GET /ws > Bad Request 0.00s
2022-09-22 15:44:24,748 <Request GET /ws > Origin=http://localhost
2022-09-22 15:44:24,749 <Request GET /ws > Bad Request 0.00s
2022-09-22 15:44:35,153 <Request GET /ws > Origin=http://localhost
2022-09-22 15:44:35,154 <Request GET /ws > Bad Request 0.00s
2022-09-22 15:44:45,865 <Request GET /ws > Origin=http://localhost
2022-09-22 15:44:45,866 <Request GET /ws > Bad Request 0.00s
2022-09-22 15:44:56,479 <Request GET /ws > Origin=http://localhost
2022-09-22 15:44:56,479 <Request GET /ws > Bad Request 0.00s
2022-09-22 15:45:06,979 <Request GET /ws > Origin=http://localhost
2022-09-22 15:45:06,979 <Request GET /ws > Bad Request 0.00s
2022-09-22 15:45:17,391 <Request GET /ws > Origin=http://localhost
2022-09-22 15:45:17,391 <Request GET /ws > Bad Request 0.00s
2022-09-22 15:45:27,793 <Request GET /ws > Origin=http://localhost
2022-09-22 15:45:27,794 <Request GET /ws > Bad Request 0.00s
2022-09-22 15:45:38,507 <Request GET /ws > Origin=http://localhost
2022-09-22 15:45:38,508 <Request GET /ws > Bad Request 0.00s
2022-09-22 15:45:49,129 <Request GET /ws > Origin=https://jnewland-codespaces-websockets-bug-697p9g29wq-3000.githubpreview.dev
2022-09-22 15:45:49,130 <Request GET /ws > Connected!