Node-Red provides both an MQTT subscribe (input) and publish (output) node. The configuration for these nodes are almost Identical as the main part of the configuration concerns the actual client connection. Because of this it is useful to think of the publish and subscribe nodes as consisting of two components as shown in the schematic below: Before we look a the actual configuration we will look at MQTT client connections in general.
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Securing Node-Red with SSL and Username Authentication
Out of the box your connection to node-red is insecure. If you are exposing node-red to the Internet or just want a more secure installation then you can: Enforce an SSL connection. Require Username and Password Authentication
Continue readingNode-Red Setup and Admin Notes
Note: Working Notes Node red uses a settings file called settings.js located in in the user .node-red folder in their home directory. You can create your own settings file and customise it either by copying the existing file or using the file available from Github here. On Linux the settings.js file is copied from the /usr/lib/node-modules/node-red/ folder to your .node-red folder in your home directory when you start node-red and there is no settings.js file is present. On windows if no settings.js file is present in the home folder then the node-red start process stops with an error. To use
Continue readingStoring Data in Node-Red Variables
Node-red nodes pass the msg object between nodes. However this object is replaced by the next msg object. So how do you store data between node calls? Node-Red provides three mechanisms: The context object -stores data for a node The Flow object – stores data for a flow The global object -stores data for the canvas
Continue readingUnderstanding The Node-Red Message Object
A node red flow consists of a series of interconnected nodes.(wired nodes). All nodes must have an input and can have 0 or multiple outputs. Nodes exchange data between each other using the msg object.
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