WebSocket Manager (wsm)

A lightweight, thread-safe WebSocket connection manager built on top of Gorilla WebSocket. It manages multiple connections by URL, with built-in send/receive channels, auto-close, and optional delayed shutdown.

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✨ Features

• Manage multiple WebSocket connections by URL.
• Thread-safe operations (open, send, receive, close).
• Buffered channels for inbound (RecvCh) and outbound (SendCh) messages.
• Auto-close on read/write errors, with optional delay.
• Context-aware ReceiveContext for timeouts and cancellation.
• Graceful cleanup (Close closes connection, channels, and removes from manager).

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📦 Installation

go get github.com/yourusername/yourrepo/wsm

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🚀 Usage

1. Create a Manager

manager := wsm.NewManager()

2. Open a Connection

// Assume `conn` is a *websocket.Conn from an HTTP upgrade
err := manager.Open("/ws/user123/notification", conn, 2*time.Second)
if err != nil {
    log.Fatal(err)
}

3. Send a Message

err = manager.Send("/ws/user123/notification", []byte("hello 👋"))
if err != nil {
    log.Println("send error:", err)
}

4. Receive a Message (blocking)

msg, err := manager.Receive("/ws/user123/notification")
if err != nil {
    log.Println("recv error:", err)
}
fmt.Println("received:", string(msg))

5. Receive with Timeout

ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
defer cancel()

msg, err := manager.ReceiveContext(ctx, "/ws/user123/notification")
if err != nil {
    log.Println("recv timeout:", err)
}

6. Close a Connection

manager.Close("/ws/user123/notification")

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🔧 API Overview

• NewManager() → create a new manager.
• Open(url, conn, closeDelay) → register a connection.
• Send(url, data) → send a message (blocks if buffer full).
• Receive(url) → blocking receive.
• ReceiveContext(ctx, url) → receive with context (timeout/cancel).
• Close(url) → close connection and cleanup.
• Exists(url) → check if a connection exists.
• GetNames() → list all active connection URLs.
• IsConnected(url) → check if connection is still alive.

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⚠️ Notes

• Backpressure: Send and Receive block if channels are full. Use larger buffer size if needed.
• AutoClose: Connections automatically close on read/write errors after the optional closeDelay.
• Safe cleanup: Manager ensures connections and channels are closed exactly once.

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