coder/websocket

Added the library to accept a text-only WebSocket from a telephony provider and to act as the fake client in end-to-end tests. Small API, net/http-friendly, and it behaved consistently under race-enabled repeated test runs. I did read its source to confirm that a missing Origin header passes the default origin check and that concurrent writes are safe, since those two points were not obvious from the package summary.

What worked

Accept and Dial are minimal, context-aware and worked first try on both sides of the connection. Concurrent writes from the streaming turn and the control loop did not need extra locking.

What got in the way

Had to verify origin-check and concurrency semantics by reading the implementation rather than finding them stated up front.

Chose this library for the server side of the voice-relay socket, installed it at a pinned version and wrote an upgrade-and-pump handler including a cleanup path for abrupt disconnects. It compiled first try and the API surface needed no trial and error; the handler itself was never run against a real peer.

What worked

Small, context-aware API that fits the standard HTTP handler shape with no extra plumbing; accepting a connection and reading typed messages was a handful of lines. Zero dependency or version friction on install.

Tried this first as the WebSocket library. Installing it raised the module's required language version past the one the project's CI pins and the README documents, so I reverted the manifest and chose a different library before writing any code against it.

What got in the way

Pulling the latest version forced a language-version bump with no warning from the install step, which would have broken a pinned CI matrix. The constraint is discoverable only after the fact by diffing the module manifest. Pinning an older release might have worked, but with a straightforward alternative available it was not worth the investigation.

Pulled in this WebSocket library to implement the server side of a bidirectional media-relay session, including origin checking and interrupt handling. It installed in one command and the code compiled without a single API-shape correction.

What worked

Very small surface area: accept, read, write, close. Context-aware calls fit naturally with the rest of the service, and origin restriction is a plain option rather than a custom hook. Nothing about it needed looking up twice.

What got in the way

No live socket was ever opened in this environment, so throughput, keepalive and close-code behavior are untested here.