Category: Node-Red

When data is read from a file or network it is read byte by byte into a data buffer. Data Buffers are temporary storage used for transferring data. To work with binary data we will need access to these buffers.

JSON is popular format for encoding data sent over the Internet, and also stored in files. In computing, JavaScript Object Notation (JSON) is an open-standard file format that uses human-readable text to transmit data objects consisting of attribute–value pairs and array data types (or any other serializable value). –wiki

In Node red any node can report status information in the visual editor. The screen shot below shows the mqtt node. It shows a green circle to indicate that it is connected and the text connected underneath the node.

There are three core http nodes. http-in -Used to configure a web server http response – used with http-in to send responses. http request – used for making http requests i.e an http client. The  http request node can be used for. Retrieving web pages from a website Making API Request Sending and receiving JSON data to a website or API. etc The node will send a request and receive the response. The node handles both the request and response. Note: if you are not familiar with the http protocol then I suggest you read the http basics tutorial.

The function node is used to run JavaScript code against the msg object. The function node accepts a msg object as input and can return 0 or more message objects as output. This message object must have a payload property (msg.payload), and usually has other properties depending on the proceeding nodes.

Installing Node Red Node-Red is a node application and before you Install node red you will need to first install node. Here are the instructions: Installing Node on Windows Installing Node on Linux Using a Package Manager Then you can Install node red on Windows and Linux (including raspberry pi) using:

To administer node-red you will need to go the admin url. The admin url is the machine name or IP address followed by the port number. e.g  127.0.0.1:1880/ if you are running the browser on the same machines as node-red. localhost:1880/ – steve-laptop:1880/ when running node-red on a remote machine 192.168.1.154:1880/ I currently run node-red on a Raspberry Pi and use a second machine (windows 10) to create flows.   Using The Node Red Admin User Interface (UI) When you open the node-red admin screen for the first time you should start with an empty work space as shown in

Node red makes it easy to save, share and move flows between computers using the export and import feature. Flows are exported as a JSON file and imported from a JSON file. You can export parts of a flow or the entire flow or even all flows.