Files
mostlymatter/vendor/github.com/gobwas/ws/doc.go
Agniva De Sarker a246104d04 MM-21012: Revamp websocket implementation (#16620)
* MM-21012: Revamp websocket implementation

We replace the old gorilla/websocket implementation with the
gobwas/ws library. The gorilla library was in maintenance mode
and had a high level API due to which we cannot use that for
situations where a large number of concurrent connections needs
to be supported.

The ws library is a very low-level library that allows us
to work with raw net.Conns. We make several improvements:

- We completely remove the reader goroutines, and instead
replace them with a manual epoll implementation which sends off
messages to be read when it receives any data on the connection.
This lets us scale to a much larger number of connections.
- The reader buffer is eliminated, because we directly read
from the connection now.

https://mattermost.atlassian.net/browse/MM-21012

```release-notes
Improved the websocket implementation by using epoll manually
to read from a websocket. As a result, the number of goroutines
is expected to go down by half.
```

* fix tests

* fix shadowing errors

* final changes

* windows support!

* Remove pointer to waitgroup

* Fix edge case

* Trigger CI

* Trigger CI

Co-authored-by: Mattermod <mattermod@users.noreply.github.com>
2021-02-13 23:42:11 +05:30

82 строки
1.7 KiB
Go

/*
Package ws implements a client and server for the WebSocket protocol as
specified in RFC 6455.
The main purpose of this package is to provide simple low-level API for
efficient work with protocol.
Overview.
Upgrade to WebSocket (or WebSocket handshake) can be done in two ways.
The first way is to use `net/http` server:
http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
conn, _, _, err := ws.UpgradeHTTP(r, w)
})
The second and much more efficient way is so-called "zero-copy upgrade". It
avoids redundant allocations and copying of not used headers or other request
data. User decides by himself which data should be copied.
ln, err := net.Listen("tcp", ":8080")
if err != nil {
// handle error
}
conn, err := ln.Accept()
if err != nil {
// handle error
}
handshake, err := ws.Upgrade(conn)
if err != nil {
// handle error
}
For customization details see `ws.Upgrader` documentation.
After WebSocket handshake you can work with connection in multiple ways.
That is, `ws` does not force the only one way of how to work with WebSocket:
header, err := ws.ReadHeader(conn)
if err != nil {
// handle err
}
buf := make([]byte, header.Length)
_, err := io.ReadFull(conn, buf)
if err != nil {
// handle err
}
resp := ws.NewBinaryFrame([]byte("hello, world!"))
if err := ws.WriteFrame(conn, frame); err != nil {
// handle err
}
As you can see, it stream friendly:
const N = 42
ws.WriteHeader(ws.Header{
Fin: true,
Length: N,
OpCode: ws.OpBinary,
})
io.CopyN(conn, rand.Reader, N)
Or:
header, err := ws.ReadHeader(conn)
if err != nil {
// handle err
}
io.CopyN(ioutil.Discard, conn, header.Length)
For more info see the documentation.
*/
package ws