api: implement several docker apis

internal/net/gphttp/gpwebsocket/writer.go

@@ -0,0 +1,29 @@
+package gpwebsocket
+
+import (
+	"context"
+
+	"github.com/coder/websocket"
+)
+
+type Writer struct {
+	conn    *websocket.Conn
+	msgType websocket.MessageType
+	ctx     context.Context
+}
+
+func NewWriter(ctx context.Context, conn *websocket.Conn, msgType websocket.MessageType) *Writer {
+	return &Writer{
+		ctx:     ctx,
+		conn:    conn,
+		msgType: msgType,
+	}
+}
+
+func (w *Writer) Write(p []byte) (int, error) {
+	return len(p), w.conn.Write(w.ctx, w.msgType, p)
+}
+
+func (w *Writer) Close() error {
+	return w.conn.CloseNow()
+}