node-red-contrib-message-queues v1.0.4

Node-RED Custom Node: Message Queue

Overview

This Node-RED custom node provides a message queue. It allows users to add messages to a queue and process them one at a time.

Features

• Message Queue Management: Add and consume messages with a structured queue.
• Simple API: Easily interact with the queue using predefined message types.

Installation

1. Clone the repository or download the source code.
2. Navigate to your Node-RED user directory (usually ~/.node-red).

3. Run the following command to install the node:

   npm install node-red-contrib-message-queues

4. Restart Node-RED.

Usage

Input Messages

The node processes input messages with the following structure:

• Add a Message to the Queue:

  {
    "type": "add",
    "payload": "message ID"
  }

  • type: Indicates the operation to perform (add).
  • payload: The unique ID of the message to add to the queue.

• Consume the Current Message:

  {
    "type": "consume",
    "payload": "message ID"
  }

  • type: Indicates the operation to perform (consume).
  • payload: The unique ID of the message currently being processed. Only the active message can be consumed.

Node Configuration

1. Drag and drop the custom node into your Node-RED flow.
2. Configure any optional settings in the node properties.
3. Connect the node to other nodes for input and output processing.

Example Workflow

1. Add Messages: Send multiple add messages to populate the queue.
2. Process Messages: Use the consume message to process the current message. Upon successful processing, the next message in the queue will be activated.

Example Screenshot

Output

• Outputs the current message being processed.
• Emits errors or status updates in case of invalid operations.