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