Update etcd client to 3.3.9

vendor/github.com/gorilla/websocket/doc.go

@@ -6,9 +6,8 @@
 //
 // Overview
 //
-// The Conn type represents a WebSocket connection. A server application uses
-// the Upgrade function from an Upgrader object with a HTTP request handler
-// to get a pointer to a Conn:
+// The Conn type represents a WebSocket connection. A server application calls
+// the Upgrader.Upgrade method from an HTTP request handler to get a *Conn:
 //
 //  var upgrader = websocket.Upgrader{
 //      ReadBufferSize:  1024,
@@ -33,7 +32,7 @@
 //      if err != nil {
 //          return
 //      }
-//      if err = conn.WriteMessage(messageType, p); err != nil {
+//      if err := conn.WriteMessage(messageType, p); err != nil {
 //          return err
 //      }
 //  }
@@ -46,8 +45,7 @@
 // method to get an io.WriteCloser, write the message to the writer and close
 // the writer when done. To receive a message, call the connection NextReader
 // method to get an io.Reader and read until io.EOF is returned. This snippet
-// snippet shows how to echo messages using the NextWriter and NextReader
-// methods:
+// shows how to echo messages using the NextWriter and NextReader methods:
 //
 //  for {
 //      messageType, r, err := conn.NextReader()
@@ -86,31 +84,23 @@
 // and pong. Call the connection WriteControl, WriteMessage or NextWriter
 // methods to send a control message to the peer.
 //
-// Connections handle received ping and pong messages by invoking a callback
-// function set with SetPingHandler and SetPongHandler methods. These callback
-// functions can be invoked from the ReadMessage method, the NextReader method
-// or from a call to the data message reader returned from NextReader.
+// Connections handle received close messages by sending a close message to the
+// peer and returning a *CloseError from the the NextReader, ReadMessage or the
+// message Read method.
 //
-// Connections handle received close messages by returning an error from the
-// ReadMessage method, the NextReader method or from a call to the data message
-// reader returned from NextReader.
-//
-// Concurrency
-//
-// Connections do not support concurrent calls to the write methods
-// (NextWriter, SetWriteDeadline, WriteMessage) or concurrent calls to the read
-// methods methods (NextReader, SetReadDeadline, ReadMessage).  Connections do
-// support a concurrent reader and writer.
-//
-// The Close and WriteControl methods can be called concurrently with all other
+// Connections handle received ping and pong messages by invoking callback
+// functions set with SetPingHandler and SetPongHandler methods. The callback
+// functions are called from the NextReader, ReadMessage and the message Read
 // methods.
 //
-// Read is Required
+// The default ping handler sends a pong to the peer. The application's reading
+// goroutine can block for a short time while the handler writes the pong data
+// to the connection.
 //
-// The application must read the connection to process ping and close messages
-// sent from the peer. If the application is not otherwise interested in
-// messages from the peer, then the application should start a goroutine to read
-// and discard messages from the peer. A simple example is:
+// The application must read the connection to process ping, pong and close
+// messages sent from the peer. If the application is not otherwise interested
+// in messages from the peer, then the application should start a goroutine to
+// read and discard messages from the peer. A simple example is:
 //
 //  func readLoop(c *websocket.Conn) {
 //      for {
@@ -121,6 +111,20 @@
 //      }
 //  }
 //
+// Concurrency
+//
+// Connections support one concurrent reader and one concurrent writer.
+//
+// Applications are responsible for ensuring that no more than one goroutine
+// calls the write methods (NextWriter, SetWriteDeadline, WriteMessage,
+// WriteJSON, EnableWriteCompression, SetCompressionLevel) concurrently and
+// that no more than one goroutine calls the read methods (NextReader,
+// SetReadDeadline, ReadMessage, ReadJSON, SetPongHandler, SetPingHandler)
+// concurrently.
+//
+// The Close and WriteControl methods can be called concurrently with all other
+// methods.
+//
 // Origin Considerations
 //
 // Web browsers allow Javascript applications to open a WebSocket connection to
@@ -138,11 +142,38 @@
 // An application can allow connections from any origin by specifying a
 // function that always returns true:
 //
-//    var upgrader = websocket.Upgrader{
+//  var upgrader = websocket.Upgrader{
 //      CheckOrigin: func(r *http.Request) bool { return true },
-//   }
+//  }
 //
-// The deprecated Upgrade function does not enforce an origin policy. It's the
-// application's responsibility to check the Origin header before calling
-// Upgrade.
+// The deprecated package-level Upgrade function does not perform origin
+// checking. The application is responsible for checking the Origin header
+// before calling the Upgrade function.
+//
+// Compression EXPERIMENTAL
+//
+// Per message compression extensions (RFC 7692) are experimentally supported
+// by this package in a limited capacity. Setting the EnableCompression option
+// to true in Dialer or Upgrader will attempt to negotiate per message deflate
+// support.
+//
+//  var upgrader = websocket.Upgrader{
+//      EnableCompression: true,
+//  }
+//
+// If compression was successfully negotiated with the connection's peer, any
+// message received in compressed form will be automatically decompressed.
+// All Read methods will return uncompressed bytes.
+//
+// Per message compression of messages written to a connection can be enabled
+// or disabled by calling the corresponding Conn method:
+//
+//  conn.EnableWriteCompression(false)
+//
+// Currently this package does not support compression with "context takeover".
+// This means that messages must be compressed and decompressed in isolation,
+// without retaining sliding window or dictionary state across messages. For
+// more details refer to RFC 7692.
+//
+// Use of compression is experimental and may result in decreased performance.
 package websocket