node-red-contrib-simple-gate

A Node-RED node for controlling message flow.

Install

Use the Node-RED Manage Palette command or run the following in your Node-RED user directory (typically ~/.node-red):

npm install node-red-contrib-simple-gate

Usage

The gate node will transmit the input message to its output when in the open state and block it when closed. Messages that arrive when the gate is closed are discarded. If it is desired to save those messages for future delivery, the q-gate node, published as node-red-contrib-queue-gate is available.

Messages with the user-defined topic Control Topic (set when the node is deployed) are not passed through but are used to control the state of the gate.

Control messages can have values representing commands for open, close, toggle, default, and status. The (case-insensitive) strings representing these commands are set by the user when the node is deployed. The status command (added in version 0.4.0) causes the node status to be refreshed, so that it can be caught by a status node. Since version 0.3.0, if a control message is received with a payload that is a number or boolean, the payload is converted to a string and then tested against the command definitions. If a command is not recognized, there is no output or change of state, and the node reports a warning.

When first deployed or after a default command, the gate is in the user-selected state defined by Default State (see below regarding persistence).

Node status

The state of the gate is indicated by a status object: text and either a green dot (open) or a red ring (closed).

State persistence

By default, the node enters the Default State on startup, either when first deployed in the editor, re-deployed as part of a modified flow or entire workspace, or when Node-RED is restarted by the user or by a system service. The state of the node is maintained in the node context, and if a persistent (non-volatile) form of context storage is available, the user has the option of restoring the state from that storage. This is done by activating the Restore from state saved in option (checkbox) in the edit dialog and choosing a non-volatile storage module from the adjacent dropdown list. (The list shows all the storage modules enabled in the Node-RED settings.js file.) If for any reason the node is unable to retrieve valid state information, it will enter the Default State. (Note: versions prior to 0.5.0 were able to use only the default context store, so that state persistence was possible only when that store was non-volatile.)

Version History

Please refer to the CHANGELOG document.

Examples

Basic Operation

This flow demonstrates the basic operation of the gate node and the commands that can be used to change its state.

[{"id":"b464bbaa.5be868","type":"gate","z":"7886adba.5d75d4","name":"gate demo","controlTopic":"control","defaultState":"open","openCmd":"open","closeCmd":"close","toggleCmd":"toggle","defaultCmd":"default","statusCmd":"status","persist":false,"x":450,"y":200,"wires":[["8ba20475.bd1c28"]]},{"id":"f61b4c1c.d6f8","type":"inject","z":"7886adba.5d75d4","name":"input","repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"","payload":"","payloadType":"date","x":150,"y":200,"wires":[["b464bbaa.5be868"]]},{"id":"57c0705e.2b648","type":"inject","z":"7886adba.5d75d4","name":"open","repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"control","payload":"open","payloadType":"str","x":250,"y":100,"wires":[["b464bbaa.5be868"]]},{"id":"e56d6ef2.db15b8","type":"inject","z":"7886adba.5d75d4","name":"close","repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"control","payload":"close","payloadType":"str","x":250,"y":140,"wires":[["b464bbaa.5be868"]]},{"id":"310d032f.aa197c","type":"inject","z":"7886adba.5d75d4","name":"toggle","repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"control","payload":"toggle","payloadType":"str","x":250,"y":260,"wires":[["b464bbaa.5be868"]]},{"id":"c5e19f28.1e37d","type":"inject","z":"7886adba.5d75d4","name":"reset","props":[{"p":"payload"},{"p":"topic","vt":"str"}],"repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"control","payload":"default","payloadType":"str","x":250,"y":300,"wires":[["b464bbaa.5be868"]]},{"id":"8ba20475.bd1c28","type":"debug","z":"7886adba.5d75d4","name":"output","active":true,"tosidebar":true,"console":false,"tostatus":false,"complete":"true","targetType":"full","statusVal":"","statusType":"auto","x":590,"y":200,"wires":[]},{"id":"7f423eb5.3d6508","type":"inject","z":"7886adba.5d75d4","name":"status","props":[{"p":"payload"},{"p":"topic","vt":"str"}],"repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"control","payload":"status","payloadType":"str","x":250,"y":340,"wires":[["b464bbaa.5be868"]]},{"id":"516d9d16.30ddac","type":"status","z":"7886adba.5d75d4","name":"gate status","scope":["b464bbaa.5be868"],"x":440,"y":260,"wires":[["f66030c4.9dce28"]]},{"id":"f66030c4.9dce28","type":"debug","z":"7886adba.5d75d4","name":"status text","active":true,"tosidebar":true,"console":false,"tostatus":false,"complete":"status.text","targetType":"msg","statusVal":"","statusType":"auto","x":590,"y":260,"wires":[]}]

Dashboard Control

This flow shows how the gate node can be controlled from the dashboard using buttons and switches.

[{"id":"d81194ef.313d6","type":"gate","z":"389e6e43.7ac652","name":"gate 1","controlTopic":"control","defaultState":"open","openCmd":"open","closeCmd":"close","toggleCmd":"toggle","defaultCmd":"default","x":450,"y":140,"wires":[["f2823cc0.7548c"]]},{"id":"a2c1bfc0.3be47","type":"status","z":"389e6e43.7ac652","name":"status 1","scope":["d81194ef.313d6"],"x":590,"y":180,"wires":[["4e7accb1.6a1244","c7ba6981.1c5ca8"]]},{"id":"ffac76df.157138","type":"inject","z":"389e6e43.7ac652","name":"timestamp","topic":"","payload":"","payloadType":"date","repeat":"","crontab":"","once":false,"onceDelay":0.1,"x":140,"y":100,"wires":[["717d6cd.b967594"]]},{"id":"5f1d51af.3f9ef8","type":"gate","z":"389e6e43.7ac652","name":"gate 2","controlTopic":"control","defaultState":"open","openCmd":"open","closeCmd":"close","toggleCmd":"toggle","defaultCmd":"default","x":450,"y":320,"wires":[["9b2a6a4.c99b098"]]},{"id":"10481de0.41060a","type":"ui_switch","z":"389e6e43.7ac652","name":"open/close","label":"open/close","group":"5cfe21d2.307938","order":3,"width":0,"height":0,"passthru":false,"decouple":"false","topic":"control","style":"","onvalue":"open","onvalueType":"str","onicon":"","oncolor":"","offvalue":"close","offvalueType":"str","officon":"","offcolor":"","x":290,"y":340,"wires":[["5f1d51af.3f9ef8"]]},{"id":"dbc56c5c.9a499","type":"ui_button","z":"389e6e43.7ac652","name":"toggle","group":"fdb6c31c.4f2818","order":3,"width":0,"height":0,"passthru":true,"label":"toggle","color":"","bgcolor":"","icon":"","payload":"toggle","payloadType":"str","topic":"control","x":310,"y":140,"wires":[["d81194ef.313d6"]]},{"id":"fb3862a9.febaa8","type":"ui_button","z":"389e6e43.7ac652","name":"reset","group":"fdb6c31c.4f2818","order":4,"width":0,"height":0,"passthru":true,"label":"reset","color":"","bgcolor":"","icon":"","payload":"default","payloadType":"str","topic":"control","x":310,"y":180,"wires":[["d81194ef.313d6"]]},{"id":"717d6cd.b967594","type":"ui_button","z":"389e6e43.7ac652","name":"message 1","group":"fdb6c31c.4f2818","order":5,"width":0,"height":0,"passthru":true,"label":"Send","color":"","bgcolor":"","icon":"","payload":"","payloadType":"date","topic":"anything","x":290,"y":100,"wires":[["d81194ef.313d6"]]},{"id":"cf3d94f3.62e01","type":"ui_button","z":"389e6e43.7ac652","name":"message 2","group":"5cfe21d2.307938","order":4,"width":0,"height":0,"passthru":false,"label":"Send","color":"","bgcolor":"","icon":"","payload":"","payloadType":"date","topic":"","x":290,"y":300,"wires":[["5f1d51af.3f9ef8"]]},{"id":"f2823cc0.7548c","type":"ui_text","z":"389e6e43.7ac652","group":"fdb6c31c.4f2818","order":2,"width":0,"height":0,"name":"display 1","label":"Message","format":"{{msg.payload}}","layout":"row-spread","x":600,"y":140,"wires":[]},{"id":"4e7accb1.6a1244","type":"ui_text","z":"389e6e43.7ac652","group":"fdb6c31c.4f2818","order":1,"width":0,"height":0,"name":"status 1","label":"Status","format":"{{msg.status.text}}","layout":"row-spread","x":740,"y":180,"wires":[]},{"id":"9b2a6a4.c99b098","type":"ui_text","z":"389e6e43.7ac652","group":"5cfe21d2.307938","order":2,"width":0,"height":0,"name":"display 2","label":"Message","format":"{{msg.payload}}","layout":"row-spread","x":600,"y":320,"wires":[]},{"id":"9fdf32be.f66568","type":"ui_text","z":"389e6e43.7ac652","group":"5cfe21d2.307938","order":1,"width":0,"height":0,"name":"status 2","label":"Status","format":"{{msg.status.text}}","layout":"row-spread","x":720,"y":360,"wires":[]},{"id":"d3b465d7.ab11d","type":"inject","z":"389e6e43.7ac652","name":"timestamp","topic":"","payload":"","payloadType":"date","repeat":"","crontab":"","once":false,"onceDelay":0.1,"x":140,"y":300,"wires":[["cf3d94f3.62e01"]]},{"id":"7378029e.0e7004","type":"status","z":"389e6e43.7ac652","name":"status 2","scope":["5f1d51af.3f9ef8"],"x":590,"y":360,"wires":[["9fdf32be.f66568"]]},{"id":"66b1fc61.8e356c","type":"inject","z":"389e6e43.7ac652","name":"toggle","topic":"","payload":"","payloadType":"date","repeat":"","crontab":"","once":false,"onceDelay":0.1,"x":150,"y":140,"wires":[["dbc56c5c.9a499"]]},{"id":"c7bd73e3.460f","type":"inject","z":"389e6e43.7ac652","name":"reset","topic":"","payload":"","payloadType":"date","repeat":"","crontab":"","once":false,"onceDelay":0.1,"x":150,"y":180,"wires":[["fb3862a9.febaa8"]]},{"id":"c7ba6981.1c5ca8","type":"debug","z":"389e6e43.7ac652","name":"","active":true,"tosidebar":true,"console":false,"tostatus":false,"complete":"status","x":750,"y":220,"wires":[]},{"id":"5cfe21d2.307938","type":"ui_group","z":"","name":"Gate #2","tab":"3616a722.b89bc8","order":2,"disp":true,"width":"6","collapse":false},{"id":"fdb6c31c.4f2818","type":"ui_group","z":"","name":"Gate #1","tab":"3616a722.b89bc8","order":1,"disp":true,"width":"6","collapse":false},{"id":"3616a722.b89bc8","type":"ui_tab","z":"","name":"Home","icon":"dashboard"}]