node-red-contrib-switch-break

The switch break director node is a mid point listener that only sits between a two nodes and listens to data traffic. If the data matches Break on value, it will send a break signal to the connected actors that disables their traffic throughput. If the data matches Accept on value, a removal of the break will be sent to all connected actors and enables their traffic again.

Fig. 2: Node appearance

Installation

In Node-RED (preferred)

• Via Manage Palette -> Search for "node-red-contrib-switch-break"

In a shell

• go to the Node-RED installation folder, e.g.: ~/.node-red
• run npm install node-red-contrib-switch-break

Usage

Fig. 3: Node explaination To give an understanding on how the node works, we can take a look at this where you have two that will listen to inputs, investigate the data send it through. When the investigation of the data is done, it can, depending on the data:

• Nothing
• Activate the break (if matching the Break on value).
• Deactivate the break (if matching the Accept on value).

When an activation of the break is done, it sends a lock signal to all connected nodes that will stop all traffic going through the actor node. And if a deactivation of the break is done, it sends a unlock signal that will let the signals of the actors through.

The second part is the . These works like a denial of service and halt the traffic when locked by the .

Fig. 3: Node appearance DATA

Node Configuration

The node configuration sets up how the should react.

Fig. 3: Node properties

Name (optional)

(Optional) The name of this node. (Will change the content of the node to the name)

Input

The value to read and validate against the Break on and Accept on values.

Break on / Accept on

The input value needs to match one of these fieds to trigger an action, or nothing will happen. As explained for the input field, the break and accept will only be sent to the connected actor nodes if matching one of these fields.

Break by default

If checked, the initial state of the and all its connected will be in a break/lock state and deny traffic going through, otherwise (if not checked), it will accept traffic.

Use timeout

If checked, then a time out can be set that will automatically reset the director's and all its connect actors to the default state.

Time out

The time to wait before returning to the default Break on default state.

The box

The box will present all the available actors that has not yet been assigned to a director. All the selected actors will be linked to this director and react to its state changes.

Node Configuration

The node configuration sets up how the should react.

Fig. 4: Node properties

Name (optional)

(Optional) The name of this node. (Will reflect what's shown on the node, but also the name in the directors list.)

Re-send last message on unlock

If checked, the last received message will be sent through as soon as this actor entering an unlocked state.

Director

Informs about the break director that is connected.

Examples

Remark: Example flows are present in the examples subdirectory. In Node-RED they can be imported via the import function and then selecting Examples in the vertical tab menu.

Example 1: Basic usage

This example shows the basic usage. The configuration simulates two different directors and two actors (one actor per director) and gives you the option to manually activate and deactive the break for a director to try out the functionality and see how it affects the actors.

example-1.json
Fig. 5: Basic usage example

Version history

v1.0.0 Initial release

Credits

• TLacke