Ethereum blockchain

Block chain

Supporting Link

https://hackernoon.com/building-a-blockchain-dapp-using-truffle-react-next-js-and-mobx-part-i-c46d218f4bdf

https://www.packtpub.com/mapt/book/big_data_and_business_intelligence/9781787122147/8/ch08lvl1sec75/introduction-to-truffle

https://www.youtube.com/watch?v=YcTSilIfih0

Download node.js msi for running npm packages

Step For installing and setupping environment

installing the environment (where we will run , compile and deploy our contract)

npm install truffle -g

To setup our local testing space. This will give give us some local account(user) where we can test our blockchain's functionalty

npm install -g ethereumjs-testrpc

To start with truffle project write the below command in CMD or Powershell for windows 10 (use powershell if CMD is not allowing the truffle.js/Module error )

inside project

truffle init

Run testrpc in another powershell/CMD window

testrpc 

open project //inside a editor make a new .sol file in contract folder Write Your contract in solidity

compile it with

truffle compile

Migrate it with

truffle migrate

Use it with the truffle console

truffle console

Sample Console to write in console

helloworl.deployed().then(function(instance){return instance.sayHello.call();}).then(function(result){console.log(result);});

Web3js Installation (please read full steps)

Pre-required tools and installation

--download and install git

--installing web3 (please read full)

While installing the web3 through npm command is

npm install web3 -save

it will clone a git repository git://github.com/frozeman/WebSocket-Node.git but it will throw a error

Cannot find git://github.com/frozeman/WebSocket-Node.git // or something like this

This is happening cause the protocol used here is git which is not so effecient in this case to you have to force to replace the protocol https instead of git .so to do that type the following command in the git bash terminal

git config --global url."https://".insteadOf git://

now your git will use https to clone it

--before installing the web 3 you need to install some more dependencies . Commands to install

npm install --global --production windows-build-tools

it will take quite long time

--After this installation now install Web3 using commands

```
npm install web3
```

Step to procced working with web3

--go to the directory where the web3 is installed

--Inside the node_module/Web3/

--If(there is a folder with names 'dist') that means its correctly installed

--Else download the web3 folder from https://codeload.github.com/ethereum/web3.js/zip/develop and replace it with the existing Web3 folder

--Now it will work fine