NodeRED/en

Introduction

Node-RED is a graphical development tool. With Node-RED, use cases for the Internet of Things can be implemented according to a simple modular principle. In Node-RED there are so-called "nodes" which look like as follows. Each node fulfills a certain function e.g. making a HTTP-request.

Node-RED Tutorial - Part 1

Preparations

• If you haven't installed Node.js yet download and install it here: https://nodejs.org/en/download/

• Use the command line to verify that Nodejs has been installed correctly.
  • To open the command line type "cmd" in the Windows search bar and press the enter key.

• After you have opened the command line type "node --version" in.

• Also type "npm --version" in the command line.
  • Hint: npm usually comes with Node.js

• Internet connection available?

Installing Node-RED

• Open command line

• Enter "npm install -g --unsafe-perm node-red" and press the enter key

• Enter "npm install node-red-node-test-helper node-red --save-dev" and press the enter key

• Enter "node-red" and press the enter key to start Node-RED

• After you have started Node-RED open your browser (Chrome, Firefox, Internet Explorer, ...)
  • Enter "localhost:1880" into the search bar of your browser and press the enter key

• Close the browser and the command line now

Node-RED Tutorial - Part 1

The following tutorial shows how to import nodes of Node-RED into expecco and how to use them.

Specify necessary paths

• Open a new testsuite in expecco

• Now you should have the following view in front of you

• Click the undo-button to remove the existing demos

• Click on Extras → Settings

• Click on Execution → External Script Interpreters → Node

• Specify at Node.js Path the path to the Node.js interpreter

• Click on the question mark next to Node.js Path to verify the node path
  • If the path is correct you will see the version of Node.js in the lower field

• Specify at Node-RED → Module Path the path to the node_modules folder
  • Click on the three points next to the field

• A small window opens
  • Click on the little house icon
  • Click on the user directory of the current user
  • Navigate in the user directory to the .node-red folder
  • Navigate to the node_modules folder
  • Select this folder and click OK
  • Your path in the field of Filename should look like C:\Users\YOUR_USERNAME\.node-red\node_modules

• Specify at Node-RED → Execution Directory the path to the .node-red folder
  • Click on the three points next to the field

• A small window opens
  • Click on the little house icon
  • Click on the user directory of the current user
  • Navigate to the .node-red folder
  • Select this folder and click OK
  • Your path in the field of Filename should look like C:\Users\YOUR_USERNAME\.node-red

• Click on Apply and then on Close

• Click YES to save the entered paths

Importing a Node

• Click on Operations → Node-RED → Importing Nodes

• A small window opens
  • Click on the little house icon
  • Click on the user directory of the current user
  • Navigate to .node-red → node_modules → @node-red → nodes → core → network
  • In this folder is a file called 21-httprequest.html
  • Select this file and click on OK

• A new folder should have been created
  • Open this folder and click on the elementary block to get the view which is shown in the picture

Using a Node in expecco

• Click on the tab Test/Demo

• Click on the elementary block keep the left mouse button pressed and drag the block a little further to the middle of the editor

• Double click on input pin url
  • Enter http://exept.de and click on OK

• Click on the green arrow to execute the block

• After you have executed the block, it takes a few seconds until you see a result
  • When you see a result click on Run

• Click on Pins → msgOut

• Scroll in the field Keys to statusCode
  • Click on statusCode
  • If the HTTP request were successful the number 200 should be in the field next to it

Hint: Keep this testsuite open if you want to continue with the second part of the tutorial

Node-RED Tutorial - Part 2

This tutorial will show you how to import Nodes from the Node-RED library into expecco

Preconditions

• Open the testsuite from tutorial - part 1
• Make sure you did the step Specify necessary paths from the first part of the tutorial before you make this part.

Collect Nodes from the Node-RED library

• Click on Operations → Collect List of Nodes in Attachment
  • The Node-RED library gets opened in a browser and the names of each node of the library get extracted and saved in the attatchment listOfNodes
  • Hint: Collecting the node names take a few minutes and offers the opportunity for a short coffee break

• Node-RED library

Installing Nodes

• Click on Operations → Install Nodes

• A window opens
  • Enter here the node name node-red-contrib-amazon-echo
  • Hint: If you want to install all nodes which contains e.g. smarthome in their names just enter *smarthome*

• The entered node will be installed
  • Information about the installation can be found in the lower left corner of the window

^

Importing the Node

• Click on Operations → Importing Nodes

• A small window opens
  • Click on the little house icon
  • Navigate to .node-red → node_modules
  • Search in this folder after a folder called node-red-contrib-amazon-echo
  • Select the file index.html, then click OK

• A new folder should have been created
  • Open this folder to see the just generated elementary blocks

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