node-red-contrib-ethereum

A node palette for interacting with ethereum clients

Node Documentation

The documentation of the nodes can be read directly in the node-RED editor by opening the 'help' section.

Installation

Prerequisites

• Install Node.js : https://nodejs.org/en/download/package-manager/
• Install Node-RED : https://nodered.org/docs/getting-started/local

Installing the node palette

• Currently this package is not available from the Node-RED Library. It must be installed using the npm package manager (comes with Node.js).

• First copy this package (node-red-contrib-ethereum) to anywhere on your machine.

• Then find the .node-red directory (usually located inside the user directory)

• From the .node-red directory run the following command to install the packge to Node-RED.

npm install <path to node-red-contrib-ethereum>

• Run Node-RED

node-red

• The console logs will show a log entry like this, where you can find the url to access the Node-RED editor from your web browser.

6 Jan 10:13:34 - [info] Server now running at http://127.0.0.1:1880/

• If everything worked out, you will find the ethereum nodes in the node palette.

Example flows

Prerequisites

• Install Truffle : https://www.trufflesuite.com/truffle
• Install Ganache : https://www.trufflesuite.com/ganache

Set up ganache workspace

• Start ganache and choose 'New Workspace'
• In the setup window, go to the 'Accounts & Keys' tab
• Enter the following mnemonic and then press 'Save Workspace'

visit carpet logic blame furnace confirm rebel deliver medal mean illness error

Deploy test smart contracts

• Find the smart contracts directory 'node-red-contrib-ethereum\example-flows\example-contracts'
• From the smart contracts directory run the commands to deploy the contracts to ganache

truffle compile
truffle migrate

• In ganache go to the 'Contracts' tab and choose 'Link Truffle Projects'
• Choose 'Add Project' and select the truffle-config.js from the smart contracts directory
• Press 'Save and Restart'
• Now you should see the deployed contracts in the 'Contracts' tab

Install the VISEO Nodes

• In Node-RED editor go to the 'Manage palette' menu
• Install the package: node-red-contrib-viseo-ethjs

Install other packages

• Install: node-red-contrib-binary
• Install: node-red-contrib-https

Import flows

• Find the file 'node-red-contrib-ethereum\example-flows\ExampleFlows.json'
• In Node-RED editor go to the 'Import' menu
• Copy & Paste the contents of ExampleFlows.json into the text field and press 'Import'

Enter Account Private Keys

• The private keys of the accounts where not part of the import, they must be entered manually
• In Node-RED editor find the 'Configuration Nodes' menu
• Enter the private keys for the following account config nodes:
• sender-account 'Account 11' : 0xfc72302ffbed8453080f1149135cfb57155d90c8e3cfa8835871d954cea50664
• ethjs-wallet 'Account 11' : 0xfc72302ffbed8453080f1149135cfb57155d90c8e3cfa8835871d954cea50664
• ethjs-wallet 'Account 2' : 0xdbbf87459bea5ca7309d9eb990f05922ab8579f4ad42364ffc229000db2ed818
• ethjs-wallet 'Account 3' : 0xde4ed0ee59a7153b7c32e5d6e25ecbfd42e94f0130be604d231169d2e67cd7f5
• Hit the 'Deploy' button
• Now the flows should be usable, try them out