node-red-contrib-resend-last-msg

A lightweight Node-RED node that allows you to resend the last received message by pressing a simple button. The node can also be controlled via an incoming message using msg._ResendLastMsg

Installation

You can install this node using the Node-RED palette manager:

1. Open Node-RED
2. Navigate to Manage Palette > Install
3. Search for node-red-contrib-resend-last-msg and install it

Alternatively, install it manually using npm:

npm install node-red-contrib-resend-last-msg

Run this command in your Node-RED user directory (typically ~/.node-red).

Usage

When this node receives a msg via input, it will:

• Pass it through to the output
• Store the message using a deep clone

The node will resend the last received message when the button is pressed.

Options:

• Resend only msg.payload (optional)
• Message Counter: The node counts received messages, and the counter can reset automatically based on configured time and days of the week.

Node Control (Version >= 1.1.0)

The node can also be controlled via an incoming message using msg._ResendLastMsg. This control property is not forwarded by the Resend Node.

1. Resend Last Message

Resend the entire message:

msg._ResendLastMsg = {
    "resend": true
}

Resend only msg.payload:

msg._ResendLastMsg = {
    "resend": "payload"
}

Resend a specific property, e.g., msg.otherMsg:

msg._ResendLastMsg = {
    "resend": "otherMsg"
}

2. Reset Stored Message

Resets the stored message and counter:

msg._ResendLastMsg = {
    "reset": true
}

3. Set Counter

Sets the message counter to a specific number:

msg._ResendLastMsg = {
    "setCounter": 10
}

• The setCounter option can be used together with other control options.
• It accepts only positive numbers; otherwise, it defaults to 0.

Examples

Examples are provided using the default node-red way, i.e. use import in the editor menu and look for examples in the node-red-contrib-resend-last-msg package

Usage Examples

The examples are available in the examples folder. You can import it directly from Node-RED.

Example Flow

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License

Licensed under the Apache License 2.0.