Dealing with multiple streams

Many times, you have to coordinate between data coming from and going to multiple streams concurrently. A simple example would be a chat room server using WebSockets. Unlike standard HTTP, which is composed of request/response pairs, WebSockets use bidirectional communication over HTTP, so you can both read from and write to the same connection. They are ideal for long-running conversations between systems where both sides send and receive data, such as this chat room example. We will develop a chat room server that accepts WebSocket connections from multiple clients. The server will distribute a message it receives from a client to all the clients connected at that moment. For this purpose, we define the following message structure:

type Message struct {
    Timestamp time.Time
    Message   string
    From      string
}

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