# Multi-Node Watch Example

This example demonstrates how to use the WebHook notification feature in a 2-node Raft cluster. Each client registers to a specific node watching **different keys**, demonstrating independent notification channels.

## Architecture

*   **Cluster**: 2 Nodes
    *   **Node 1**: Raft Port 9500, HTTP API Port 8500
    *   **Node 2**: Raft Port 9501, HTTP API Port 8501
*   **Clients**: 2 Listeners
    *   **Client 1**: Listens on 9600, Subscribes to Node 1 for `key-1`
    *   **Client 2**: Listens on 9601, Subscribes to Node 2 for `key-2`

## Running the Example

You will need 4 terminal windows.

### 1. Start the Cluster Nodes

**Terminal 1 (Node 1):**
```bash
cd example/watch/node1
go run main.go
```

**Terminal 2 (Node 2):**
```bash
cd example/watch/node2
go run main.go
```

Wait a moment for them to elect a leader.

### 2. Start the Clients

**Terminal 3 (Client 1):**
```bash
cd example/watch/client1
go run main.go
```
*This will start a listener and auto-subscribe to Node 1 for `key-1`.*

**Terminal 4 (Client 2):**
```bash
cd example/watch/client2
go run main.go
```
*This will start a listener and auto-subscribe to Node 2 for `key-2`.*

### 3. Trigger Data Changes

You can trigger changes by sending a request to **ANY** node's HTTP API. Since the clients are watching different keys, you can target specific clients.

**Trigger Client 1 (via Node 1):**
```bash
# Sets key-1, Client 1 should notify
curl -X POST http://127.0.0.1:8500/kv \
     -H "Content-Type: application/json" \
     -d '{"key": "key-1", "value": "hello-client-1"}'
```

**Trigger Client 2 (via Node 1):**
```bash
# Sets key-2, replicated to Node 2, Client 2 should notify
curl -X POST http://127.0.0.1:8500/kv \
     -H "Content-Type: application/json" \
     -d '{"key": "key-2", "value": "hello-client-2"}'
```

### 4. Expected Output

*   When you set `key-1`, only **Client 1** should output a notification.
*   When you set `key-2`, only **Client 2** should output a notification.

This demonstrates that notifications are filtered by key and dispatched locally by the node holding the subscription, even though the data is consistent across the entire cluster.