Relates to CODAGT-115
Adds metric `coderd_api_websocket_probes_total`. Every successful
heartbeat for a given path will increment the metric.
Comparing this with `coderd_api_concurrent_websockets` will give an
indication of how many websocket connections are open but in a 'wedged'
state (when heartbeats stopped versus when we closed the connection).
The `mockEventSenderWrite` function in `newOneWayWriter()` wrote
WebSocket frame data to both the `net.Pipe` and the
`httptest.ResponseRecorder`. After `websocket.Accept()` calls
`WriteHeader(101)`, the recorder rejects body writes with `"response
status code does not allow body"`. When `HeartbeatClose` sends a ping,
the control frame flush routes through the recorder, producing an
ERROR-level log that `slogtest` catches as a test failure.
Removed the `recorder.Write(b)` call from the write function. The
recorder is only needed for header/status inspection; WebSocket frame
data should only go through the `net.Pipe`.
Closes https://github.com/coder/internal/issues/1521
> 🤖 Generated by Coder Agents
Relates to https://github.com/coder/coder/pull/21676
* Replaces all existing usages of `httpapi.Heartbeat` with `httpapi.HeartbeatClose`
* Removes `httpapi.HeartbeatClose`
Closes https://github.com/coder/coder/issues/16775
## Changes made
- Added `OneWayWebSocket` function that establishes WebSocket
connections that don't allow client-to-server communication
- Added tests for the new function
- Updated API endpoints to make new WS-based endpoints, and mark
previous SSE-based endpoints as deprecated
- Updated existing SSE handlers to use the same core logic as the new WS
handlers
## Notes
- Frontend changes handled via #16855
* chore: add /v2 to import module path
go mod requires semantic versioning with versions greater than 1.x
This was a mechanical update by running:
```
go install github.com/marwan-at-work/mod/cmd/mod@latest
mod upgrade
```
Migrate generated files to import /v2
* Fix gen
It's possible for websocket close messages to be too long, which cause
them to silently fail without a proper close message. See error below:
```
2022-03-31 17:08:34.862 [INFO] (stdlib) <close_notjs.go:72> "2022/03/31 17:08:34 websocket: failed to marshal close frame: reason string max is 123 but got \"insert provisioner daemon:Cannot encode []database.ProvisionerType into oid 19098 - []database.ProvisionerType must implement Encoder or be converted to a string\" with length 161"
```
* chore: Move httpmw to /coderd directory
httpmw is specific to coderd and should be scoped under coderd
* chore: Move httpapi to /coderd directory
httpapi is specific to coderd and should be scoped under coderd
* chore: Move database to /coderd directory
database is specific to coderd and should be scoped under coderd
* chore: Update codecov & gitattributes for generated files
* chore: Update Makefile
Cian Johnston