PSA: Changes to Chrome’s WebSocket Server used in DevTools protocol to improve standard compliance

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Shiho Noda

Sep 17, 2021, 11:42:09 AMSep 17

Dear blink devs

If you don’t use the DevTools protocol, you can ignore this.
This server is only used in headless or remote-control scenarios, and is not part of the web platform.
DevTools uses Chrome internal WebSocket implementation. The previous implementation was not compliant with the WebSocket standard [1]. Therefore, I fixed it by supporting fragmented messages and ping and pong frames.

The server now accepts fragmented messages and concatenates the frames correctly.
When the server receives a ping frame, it responds with a pong frame in compliance with the standard:

When the server receives pong frames, it accepts them and doesn't close the connection.

There are no changes for people who don’t use fragmented messages or ping/pong frames. People who want to use them will find they work now.

Shiho Noda

Mathias Bynens

Sep 21, 2021, 8:56:19 AMSep 21
to Shiho Noda, blink-dev,,,
For those wondering (like me), the relevant tracking bug is

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