This is part 3 of my Ethereum IOT Kid Ground Device project. In this part, we will discuss the codes of the web service backend written in Node.js and running as a server application. You may read part 1 here and part 2 here.

This is part 2 of my Ethereum IOT Kid Grounding Device project. In this part, we will discuss the business logic behind Grounder.sol, the Smart Contract that does the real work behind grounding my kid. You may read part 1 here.

I like to equate Smart Contract to the business logic layer of conventional apps which developers would have developed as JSON web services in tools such as node.js (if you like JavaScript) or django (if you like Python).

Internet of Trusted Things (IOTT) is a recently-coined term that explores the integration of Internet of Things (IOT) with Blockchain.

Solidity as a programming language has been most intriguing for me because of its many features that I haven't come across in languages that I have been more familiar with. One example is the underscore like the one in line 10 below.

This article explores the technique of getting one Smart Contract to call another Smart Contract and is a follow-up to the Escrow Service article that I wrote in May 2018. The Safe Remote Purchase Smart Contract is, in my opinion, the clearest example to explain Smart Contracts to anyone who needs to understand what it does. Safe Remote Purchase has several quirky characteristics. In this article, I will explain one of them.

Syncing to the Ethereum Blockchain has always been a challenge particularly for me.

This is the final part of the Lottery Smart Contract series that I started 2 weeks ago. You are read part 1 here and part 2 here. In this final part I will be walking through the codes of the Lottery Smart Contract to explain what some of the more important lines of codes do. 

The Codes

This is part 2 of the "Lottery as a Smart Contract" series. In part 1, I described the business logic behind the Lottery Smart Contract. Here, I will demonstrate how this contract is executed. To run this, you will need:

Writing a lottery contract is a great way to learn important Smart Contract concepts such as State, Event and Visibility. In this 3 part series, I will describe the logic and codes behind a Lottery Smart Contract. In developing my Lottery Contract, I used Oraclize, a data carrier service that executes external JSON web services.

Motivation

This is a continuation of Part 1 where I described how Safe Remote Purchase works. In this blog post, I will document the process of executing the Safe Remote Purchase Smart Contract using Remix Solidity IDE and MetaMask, running on a Google Chrome browser.

MetaMask