Ethereum / Raiden Research

[robertDurst]

After CryptoKitties clogged Ethereum, not so sure about this option. But, I will still check it out.

[robertDurst]

Docker-Ethereum: https://hub.docker.com/r/ethereum/client-go/
Raiden (with Docker): https://github.com/raiden-network/raiden/?fref=ts

Some Ethereum Tutorials: https://souptacular.gitbooks.io/ethereum-tutorials-and-tips-by-hudson/content/index.html

[robertDurst]

Used this tutorial and got two nodes up and talking.

https://blockgeeks.com/two-node-setup-of-a-private-ethereum/

[robertDurst]

Ethereum Private Network and Hello World 3.0

Setup Node Ubuntu

Install necessary stuff

mkdir ~/ethereum
cd ~/ethereum
sudo apt-get install software-properties-common
sudo add-apt-repository -y ppa:ethereum/ethereum
sudo apt-get update
sudo apt-get install ethereum

Setup Genesis.json

vim Genesis.json  -- or nano if ur a noob

Here is the setup I use. Notice the difficulty. Yeah I have no patience and am using questionable hardware so let's use a difficulty of 1.

{
"config": {
"chainId": 15,
"homesteadBlock": 0,
"eip155Block": 0,
"eip158Block": 0
},
"nonce": "0x0000000000000042",
"mixhash": "0x0000000000000000000000000000000000000000000000000000000000000000",
"difficulty": "0x001",
"alloc": {},
"coinbase": "0x0000000000000000000000000000000000000000",
"timestamp": "0x00",
"parentHash": "0x0000000000000000000000000000000000000000000000000000000000000000",
"gasLimit": "0xffffffff",
"alloc": {
}
}

Start up it up!

geth init Genesis.json

Launch Geth, the interactive console for Ethereum (Geth = Go + Etherem)

geth --nodiscover console 2>> eth.log

Open up a NEW terminal to display a log (useful for debugging and fun to watch)

tail -F eth.log

Back in terminal 1, setup a new account and check the balance (hint: it should be 0)

personal.newAccount()
eth.getBalance(eth.accounts[0])

Setup Node Mac

Exactly the same as above except run the following to install all the stuff:

brew tap ethereum/ethereum
brew install ethereum

Connect two nodes

Get Node 1's address

admin

Look under node info (enode)

Connect to Node 1 from Node 2

admin.addPeer('enode://cf2bd74b1b0ddc3240037213f8a074554c75ccde432a0eb1ec0a9a87cbe15c44a8b585626575c2141c06f32d7d86c8c91b240ae1f9dff4debff75e5ced474d0e@<ADDRESS_OF_NODE_1>:30303?discport=0')

Verify the connection is made on both Nodes

admin.peers

Mine some blocks

So I realized after an hour of waiting that my $5 DigitalOcean droplets weren't going to mine a block anytime soon... even with the low difficulty. Thus, I ended up using my macbook as the miner whenever I wanted something mined.

Here is how you get started mining (I am using the account I created above):

miner.setEtherbase(eth.accounts[0])
miner.start()

In case it isn't obvious, you stop the miner with:

miner.stop()

Mining is necessary whenever you need:
a) to fund an account
b) to send a transaction
c) to execute a smart contract
d) to heat up your computer

Hello World Contract

Here is a nice contract to get started with:

contract mortal {
    /* Define variable owner of the type address */
    address owner;

    /* This function is executed at initialization and sets the owner of the contract */
    function mortal() { owner = msg.sender; }

    /* Function to recover the funds on the contract */
    function kill() { if (msg.sender == owner) selfdestruct(owner); }
}

contract greeter is mortal {
    /* Define variable greeting of the type string */
    string greeting;
    
    /* This runs when the contract is executed */
    function greeter(string _greeting) public {
        greeting = _greeting;
    }

    /* Main function */
    function greet() constant returns (string) {
        return greeting;
    }
}

Basically, this does two things:
a) greet: returns whatever string the contract was initiated with
b) kill: destroys the contrac

To deploy this, follow these six steps:

1. Copy and paste this code into the compiler at remix.ethereum.org:

2. On the right click details and grab the code under "WEB3DEPLOY" which should look similar to this (I copied a slightly different version here):

var _greeting = /* var of type string here */ ;
var browser_greeter_sol_greeterContract = web3.eth.contract([{"constant":false,"inputs":[],"name":"kill","outputs":[],"payable":false,"stateMutability":"nonpayable","type":"function"},{"constant":true,"inputs":[],"name":"greet","outputs":[{"name":"","type":"string"}],"payable":false,"stateMutability":"view","type":"function"},{"inputs":[{"name":"_greeting","type":"string"}],"payable":false,"stateMutability":"nonpayable","type":"constructor"}]);
var browser_greeter_sol_greeter = browser_greeter_sol_greeterContract.new(
   _greeting,
   {
     from: web3.eth.accounts[0], 
     data: '0x6060604052341561000f57600080fd5b60405161034438038061034483398101604052808051820191905050336000806101000a81548173ffffffffffffffffffffffffffffffffffffffff021916908373ffffffffffffffffffffffffffffffffffffffff1602179055508060019080519060200190610081929190610088565b505061012d565b828054600181600116156101000203166002900490600052602060002090601f016020900481019282601f106100c957805160ff19168380011785556100f7565b828001600101855582156100f7579182015b828111156100f65782518255916020019190600101906100db565b5b5090506101049190610108565b5090565b61012a91905b8082111561012657600081600090555060010161010e565b5090565b90565b6102088061013c6000396000f30060606040526004361061004c576000357c0100000000000000000000000000000000000000000000000000000000900463ffffffff16806341c0e1b514610051578063cfae321714610066575b600080fd5b341561005c57600080fd5b6100646100f4565b005b341561007157600080fd5b610079610185565b6040518080602001828103825283818151815260200191508051906020019080838360005b838110156100b957808201518184015260208101905061009e565b50505050905090810190601f1680156100e65780820380516001836020036101000a031916815260200191505b509250505060405180910390f35b6000809054906101000a900473ffffffffffffffffffffffffffffffffffffffff1673ffffffffffffffffffffffffffffffffffffffff163373ffffffffffffffffffffffffffffffffffffffff161415610183576000809054906101000a900473ffffffffffffffffffffffffffffffffffffffff1673ffffffffffffffffffffffffffffffffffffffff16ff5b565b61018d6101c8565b6040805190810160405280600f81526020017f48656c6c6f20576f726c6420332e300000000000000000000000000000000000815250905090565b6020604051908101604052806000815250905600a165627a7a723058204f03783520c6602ca4c5436e8cbb4dcf0b880ef3f6385f0a4579a9a2f1bad6a80029', 
     gas: '4700000'
   }, function (e, contract){
    console.log(e, contract);
    if (typeof contract.address !== 'undefined') {
         console.log('Contract mined! address: ' + contract.address + ' transactionHash: ' + contract.transactionHash);
    }
 })

3. Paste this code into the geth console
4. Mine some blocks. When the contract has been mined, you'll see a message:

5) Run the contract: ``` browser_greeter_sol_greeter.greet() ``` Here was my output:

6) Pop a bottle, cheers you're now a on your way to becoming a Dapp developer!

SOURCE for most of this: https://blockgeeks.com/two-node-setup-of-a-private-ethereum/
SOURCE for Mac: https://medium.com/@niceoneallround/creating-a-private-ethereum-network-on-a-mac-c417ab971055
Remix: https://remix.ethereum.org
SOURCE for smart contract: https://github.com/ethereum/go-ethereum/wiki/Contract-Tutorial

[robertDurst]

Importing a contract with Web3 in Geth Console

Provide default Eth account for Web3

web3.eth.defaultAccount = web3.eth.accounts[0];

Find ABI. We will again use Remix for this.

Import the ABI

var contractInstance = web3.eth.contract(<INSERT_ABI_HERE>);

Connect to Address

var contract = contractInstance.at(<CONTRACT_ADDRESS>);

Check to make sure it worked

console.log(contract) --> [object Object]

Now you can run functions on the contract (don't forget that you need gas for this)

contract.function()

SOURCE: https://coursetro.com/posts/code/99/Interacting-with-a-Smart-Contract-through-Web3.js-(Tutorial)

[robertDurst]

A good place for starting to write real contracts: https://github.com/OpenZeppelin/zeppelin-solidity

[robertDurst]

Some more links for reference:

Raiden

https://github.com/raiden-network
https://raiden.network/

Current Version of Architecture

https://www.lucidchart.com/invitations/accept/e049c95b-f3a0-4d09-aa41-d1eef3ba6ccb

Multisignatures in Ethereum

https://github.com/christianlundkvist/simple-multisig/blob/master/test/simplemultisig.js
ethereum/EIPs#191
https://medium.com/@ChrisLundkvist/exploring-simpler-ethereum-multisig-contracts-b71020c19037