node-red-contrib-redis-variable/redis-variable.html

A comprehensive Node-RED node for Redis operations with universal payload-based configuration, automatic JSON handling, SSL/TLS support, and advanced pattern matching with pagination

<script type="text/javascript">
    RED.nodes.registerType("redis-variable", {
        category: "Redis",
        color: "#D8BFD8",
        defaults: {
            name: { value: "" },
            redisConfig: { value: "", type: "redis-variable-config" },
            operation: { value: "get" }
        },
        inputs: 1,
        outputs: 1,
        icon: "font-awesome/fa-database",
        label: function() {
            return this.name || "Redis (" + (this.operation || "get") + ")";
        }
    });
</script>

<script type="text/html" data-template-name="redis-variable">
    <div class="form-row">
        <label for="node-input-name"><i class="fa fa-tag"></i> Name</label>
        <input type="text" id="node-input-name" placeholder="Name">
    </div>
    <div class="form-row">
        <label for="node-input-redisConfig"><i class="fa fa-cog"></i> Redis Config</label>
        <input type="text" id="node-input-redisConfig">
    </div>
    <div class="form-row">
        <label for="node-input-operation"><i class="fa fa-tasks"></i> Operation</label>
        <select id="node-input-operation">
            <optgroup label="Basic Operations">
                <option value="get">GET - Get value</option>
                <option value="set">SET - Set value</option>
                <option value="del">DEL - Delete key</option>
                <option value="exists">EXISTS - Check if key exists</option>
                <option value="match">MATCH - Find keys by pattern</option>
            </optgroup>
            <optgroup label="TTL Operations">
                <option value="ttl">TTL - Get time to live</option>
                <option value="expire">EXPIRE - Set expiration</option>
                <option value="persist">PERSIST - Remove expiration</option>
            </optgroup>
            <optgroup label="Counter Operations">
                <option value="incr">INCR - Increment by 1</option>
                <option value="decr">DECR - Decrement by 1</option>
                <option value="incrby">INCRBY - Increment by N</option>
                <option value="decrby">DECRBY - Decrement by N</option>
            </optgroup>
            <optgroup label="List Operations">
                <option value="lpush">LPUSH - Push to left</option>
                <option value="rpush">RPUSH - Push to right</option>
                <option value="lpop">LPOP - Pop from left</option>
                <option value="rpop">RPOP - Pop from right</option>
                <option value="llen">LLEN - List length</option>
                <option value="lrange">LRANGE - Get range</option>
            </optgroup>
            <optgroup label="Hash Operations">
                <option value="hset">HSET - Set hash field</option>
                <option value="hget">HGET - Get hash field</option>
                <option value="hgetall">HGETALL - Get all fields</option>
                <option value="hdel">HDEL - Delete hash field</option>
            </optgroup>
            <optgroup label="Pub/Sub Operations">
                <option value="publish">PUBLISH - Publish message</option>
            </optgroup>
        </select>
    </div>
</script>

<script type="text/x-red" data-help-name="redis-variable">
    <p>Redis node for comprehensive operations with universal payload-based configuration.</p>
    
    <h3>Configuration</h3>
    <p>Select or create a Redis configuration that contains your connection settings.</p>
    
    <h3>Operations</h3>
    
    <h4>Basic Operations</h4>
    <ul>
        <li><b>GET</b>: Retrieve value by key</li>
        <li><b>SET</b>: Store value with key (supports TTL)</li>
        <li><b>DEL</b>: Delete key(s)</li>
        <li><b>EXISTS</b>: Check if key(s) exist</li>
        <li><b>MATCH</b>: Find keys by pattern using SCAN</li>
    </ul>
    
    <h4>TTL Operations</h4>
    <ul>
        <li><b>TTL</b>: Get remaining time to live in seconds</li>
        <li><b>EXPIRE</b>: Set expiration time for existing key</li>
        <li><b>PERSIST</b>: Remove expiration from key</li>
    </ul>
    
    <h4>Counter Operations</h4>
    <ul>
        <li><b>INCR</b>: Increment value by 1</li>
        <li><b>DECR</b>: Decrement value by 1</li>
        <li><b>INCRBY</b>: Increment value by N</li>
        <li><b>DECRBY</b>: Decrement value by N</li>
    </ul>
    
    <h4>List Operations</h4>
    <ul>
        <li><b>LPUSH</b>: Add element to beginning of list</li>
        <li><b>RPUSH</b>: Add element to end of list</li>
        <li><b>LPOP</b>: Remove and return first element</li>
        <li><b>RPOP</b>: Remove and return last element</li>
        <li><b>LLEN</b>: Get list length</li>
        <li><b>LRANGE</b>: Get range of elements</li>
    </ul>
    
    <h4>Hash Operations</h4>
    <ul>
        <li><b>HSET</b>: Set hash field value</li>
        <li><b>HGET</b>: Get hash field value</li>
        <li><b>HGETALL</b>: Get all hash fields</li>
        <li><b>HDEL</b>: Delete hash field(s)</li>
    </ul>
    
    <h4>Pub/Sub Operations</h4>
    <ul>
        <li><b>PUBLISH</b>: Publish message to channel</li>
    </ul>
    
    <h3>Universal Payload Format</h3>
    <p>All parameters are passed via <code>msg.payload</code>. The payload can be a string (for simple operations) or an object with specific properties.</p>
    
    <h3>Examples</h3>
    
    <h4>Basic Operations</h4>
    <pre>// GET - simple format
{
  "payload": "user:123"
}

// GET - object format
{
  "payload": {"key": "user:123"}
}

// SET with value
{
  "payload": {
    "key": "user:123",
    "value": "John Doe"
  }
}

// SET with TTL (expires in 1 hour)
{
  "payload": {
    "key": "session:abc123",
    "value": {"userId": 42, "role": "admin"},
    "ttl": 3600
  }
}

// DELETE multiple keys
{
  "payload": {
    "keys": ["cache:page1", "cache:page2", "temp:data"]
  }
}

// MATCH - Find keys by pattern
{
  "payload": {
    "pattern": "user:*",
    "count": 100
  }
}

// MATCH - With pagination (cursor)
{
  "payload": {
    "pattern": "user:*",
    "count": 50,
    "cursor": "12345"
  }
}

// MATCH - Skip first N keys
{
  "payload": {
    "pattern": "session:*",
    "count": 30,
    "skip": 100
  }
}

// MATCH - Simple pattern
{
  "payload": "session:*"
}</pre>
    
    <h4>TTL Operations</h4>
    <pre>// Check TTL
{
  "payload": "session:abc123"
}

// Set expiration
{
  "payload": {
    "key": "temp:data",
    "ttl": 1800
  }
}

// Remove expiration
{
  "payload": "permanent:key"
}</pre>
    
    <h4>Counter Operations</h4>
    <pre>// Increment by 1
{
  "payload": "page:views"
}

// Increment by amount
{
  "payload": {
    "key": "score:player1",
    "amount": 100
  }
}</pre>
    
    <h4>List Operations</h4>
    <pre>// Add to list
{
  "payload": {
    "key": "queue:tasks",
    "value": {"task": "process_order", "id": 123}
  }
}

// Get range
{
  "payload": {
    "key": "queue:tasks",
    "start": 0,
    "stop": 9
  }
}

// Pop from list
{
  "payload": "queue:tasks"
}</pre>
    
    <h4>Hash Operations</h4>
    <pre>// Set single field
{
  "payload": {
    "key": "user:123",
    "field": "email",
    "value": "user@example.com"
  }
}

// Set multiple fields
{
  "payload": {
    "key": "user:123",
    "fields": {
      "name": "John Doe",
      "age": 30,
      "city": "New York"
    }
  }
}

// Get field
{
  "payload": {
    "key": "user:123",
    "field": "email"
  }
}

// Get all fields
{
  "payload": "user:123"
}</pre>
    
    <h4>Pub/Sub Operations</h4>
    <pre>// Publish message
{
  "payload": {
    "channel": "notifications",
    "message": {
      "type": "alert",
      "text": "System maintenance"
    }
  }
}</pre>
    
    <h3>Automatic JSON Handling</h3>
    <p>The node automatically detects and handles JSON data:</p>
    <ul>
        <li><b>When storing</b>: JavaScript objects are automatically serialized to JSON strings</li>
        <li><b>When retrieving</b>: Valid JSON strings are automatically parsed back to objects</li>
        <li><b>Simple values</b>: Strings, numbers, and other simple types are handled as-is</li>
        <li>Applies to all operations that handle values (GET, SET, lists, hashes, pub/sub)</li>
    </ul>
    
    <h3>Output Examples</h3>
    <ul>
        <li><b>GET</b>: Returns the stored value (auto-parsed if JSON)</li>
        <li><b>SET</b>: <code>{ success: true, result: "OK", ttl: 3600 }</code></li>
        <li><b>TTL</b>: <code>{ key: "mykey", ttl: 3600, status: "expires in 3600 seconds" }</code></li>
        <li><b>INCR</b>: <code>{ key: "counter", value: 42 }</code></li>
        <li><b>LPUSH</b>: <code>{ success: true, key: "list", length: 5, operation: "lpush" }</code></li>
        <li><b>HGETALL</b>: <code>{ name: "John", age: 30, email: "john@example.com" }</code> (auto-parsed)</li>
        <li><b>MATCH</b>: <code>{ pattern: "user:*", keys: ["user:1", "user:2"], count: 2, limit: 50, cursor: "12345", truncated: false }</code></li>
    </ul>
    
    <h4>MATCH Operation Details</h4>
    <p>The MATCH operation supports advanced features for efficient key discovery:</p>
    <ul>
        <li><b>Pattern matching</b>: Uses Redis SCAN with pattern matching (e.g., <code>user:*</code>, <code>session:ci_session:*</code>)</li>
        <li><b>Count limit</b>: Limit the number of keys returned (default: 100)</li>
        <li><b>Cursor pagination</b>: Use <code>cursor</code> parameter for efficient pagination through large datasets</li>
        <li><b>Skip keys</b>: Use <code>skip</code> parameter to skip the first N matching keys</li>
        <li><b>Performance optimized</b>: Uses Redis SCAN for non-blocking operation on large datasets</li>
    </ul>
    
    <p><b>Response format:</b></p>
    <pre>{
  "pattern": "user:*",
  "keys": ["user:1", "user:2", "user:3"],
  "count": 3,
  "limit": 50,
  "cursor": "67890",        // Next cursor for pagination
  "startCursor": "0",       // Starting cursor
  "scanned": true,
  "truncated": false        // true if results were limited by count
}</pre>
    
    <p><b>Pagination example:</b></p>
    <pre>// First request
{
  "payload": {
    "pattern": "session:*",
    "count": 30
  }
}

// Response contains cursor for next page
// Use that cursor in next request
{
  "payload": {
    "pattern": "session:*",
    "count": 30,
    "cursor": "67890"  // from previous response
  }
}

// Continue until cursor becomes "0" (end of results)</pre>
</script>