We will introduce how to build development environment of smart contract in this blog and you will get the method how to kick off with a simple “Hello World” demo.
We will use Remix-Solidity IDE and this is the easier way to start due to you do not need install Solidity, you can still install Solidity as you will.
AlfreddeMacBook-Pro:~ alfred$ brew tap ethereum/ethereum
Updating Homebrew...
==> Downloading https://homebrew.bintray.com/bottles-portable-ruby/portable-ruby-2.3.7.leopard_64.bottle.tar.gz
######################################################################## 100.0%
==> Pouring portable-ruby-2.3.7.leopard_64.bottle.tar.gz
==> Auto-updated Homebrew!
Updated 1 tap (homebrew/core).
==> New Formulae
...(省略部分列表）
==> Renamed Formulae
cdiff -> ydiff latexila -> gnome-latex php71 -> php@7.1
crystal-lang -> crystal php56 -> php@5.6 saltstack -> salt
geth -> ethereum php70 -> php@7.0 wpcli-completion -> wp-cli-completion
==> Deleted Formulae
arm bokken i3status mal4s nazghul voltdb
artifactory-cli-go ecj llvm@3.8 mimetic picolisp wry
aws-cloudsearch i3 luciddb monotone ufoai
==> Tapping ethereum/ethereum
Cloning into '/usr/local/Homebrew/Library/Taps/ethereum/homebrew-ethereum'...
remote: Counting objects: 6, done.
remote: Compressing objects: 100% (6/6), done.
remote: Total 6 (delta 1), reused 0 (delta 0), pack-reused 0
Unpacking objects: 100% (6/6), done.
Tapped 3 formulae (33 files, 33.6KB).
AlfreddeMacBook-Pro:~ alfred$ brew install ethereum
Updating Homebrew...
==> Downloading https://homebrew.bintray.com/bottles/ethereum-1.8.12.high_sierra.bottle.tar.gz
######################################################################## 100.0%
==> Pouring ethereum-1.8.12.high_sierra.bottle.tar.gz
🍺 /usr/local/Cellar/ethereum/1.8.12: 20 files, 228MB
Geth is a ethereum client, now we start an ethereum network node with geth
AlfreddeMacBook-Pro:chenjingchao alfred$ mkdir blockchain
AlfreddeMacBook-Pro:chenjingchao alfred$ cd blockchain/
AlfreddeMacBook-Pro:blockchain alfred$ ls
AlfreddeMacBook-Pro:blockchain alfred$ geth --datadir testNet --dev console 2>> test.log
Welcome to the Geth JavaScript console!
instance: Geth/v1.8.12-stable/darwin-amd64/go1.10.3
coinbase: 0xf70888b4f9f3f10f13ac7939765636dbef62b77c
at block: 0 (Thu, 01 Jan 1970 08:00:00 CST)
datadir: /Users/alfred/chenjingchao/blockchain/testNet
modules: admin:1.0 clique:1.0 debug:1.0 eth:1.0 miner:1.0 net:1.0 personal:1.0 rpc:1.0 shh:1.0 txpool:1.0 web3:1.0
>
–dev means develope network mode, POA will be used by this mode and a developer account will preallocated which surpport automatic mining.
–datadir meas the directory where the block data and key stored, a testNet directory will created when you input the command first time.
console just the console.
2» test.log console log output to test.log
> eth.accounts
["0xf70888b4f9f3f10f13ac7939765636dbef62b77c"]
>
or
> personal.listAccounts
["0xf70888b4f9f3f10f13ac7939765636dbef62b77c"]
>
> eth.getBalance(eth.accounts[0])
1.15792089237316195423570985008687907853269984665640564039457584007913129639927e+77
>
eth.accounts[0] means the first one of account list, it shows pretty huge balance when you click the enter.
Beacause of much balance in developer account, nothing changed shall we see when deploying contract. We choose create a new account in terms of better show.
> personal.newAccount("jingchao")
"0xe78bd82783486461e47028a216f441064adb6db7"
>
“jingchao” is password of the new account, it returns a new account as clicking the Enter.
check the account list
> eth.accounts
["0xf70888b4f9f3f10f13ac7939765636dbef62b77c", "0xe78bd82783486461e47028a216f441064adb6db7"]
>
We will see there have 2 accounts including the one we just created which index number is “1”, and also you can check it in the way below as you will get the same result.
> personal.listAccounts
["0xf70888b4f9f3f10f13ac7939765636dbef62b77c", "0xe78bd82783486461e47028a216f441064adb6db7"]
>
check the balance of new account
> eth.getBalance(eth.accounts[1])
0
>
> eth.sendTransaction({from: '0xf70888b4f9f3f10f13ac7939765636dbef62b77c', to: '0xe78bd82783486461e47028a216f441064adb6db7', value: web3.toWei(1, "ether")})
"0xc29da3bf5a9af4eb6279c0938196690a306a5ed132e08b17d1367647da93d16d"
> eth.getBalance(eth.accounts[1])
1000000000000000000
>
> personal.unlockAccount(eth.accounts[1], "jingchao");
true
>
Open Browser-Solidity and write code, click ‘details’ to deploy.
Find the part tagged with “WEB3DEPLOY” and click copy button, modify initial string to “Hello World” after pasting the part into editor.
> var _greeting = "Hello World" ;
undefined
> var helloContract = web3.eth.contract([{"constant":true,"inputs":[],"name":"say","outputs":[{"name":"","type":"string"}],"payable":false,"stateMutability":"view","type":"function"},{"inputs":[{"name":"_greeting","type":"string"}],"payable":false,"stateMutability":"nonpayable","type":"constructor"}]);
undefined
> var hello = helloContract.new(
... _greeting,
... {
...... from: web3.eth.accounts[0],
...... data: '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',
...... gas: '4700000'
...... }, function (e, contract){
...... console.log(e, contract);
...... if (typeof contract.address !== 'undefined') {
......... console.log('Contract mined! address: ' + contract.address + ' transactionHash: ' + contract.transactionHash);
......... }
...... })
null [object Object]
undefined
> null [object Object]
Contract mined! address: 0x528754900317f565cd18328c430ed71cdb0db239 transactionHash: 0xa75702df9f7729a8c93a6b2616fa4c6a8faea5c3193b103c58d22cb7b105756d
null [object Object]
Contract mined! address: 0xf4a443f2febe597c7ba665cd45378b7f962d32fd transactionHash: 0x1bb023ea80bc3a07e8078d0ccde6ffa3081d67f5a1a4a7460de305a7e2b2f832
Contact has been deployed successfully.
check hello
> hello
{
abi: [{
constant: true,
inputs: [],
name: "say",
outputs: [{...}],
payable: false,
stateMutability: "view",
type: "function"
}, {
inputs: [{...}],
payable: false,
stateMutability: "nonpayable",
type: "constructor"
}],
address: "0xf4a443f2febe597c7ba665cd45378b7f962d32fd",
transactionHash: "0x1bb023ea80bc3a07e8078d0ccde6ffa3081d67f5a1a4a7460de305a7e2b2f832",
allEvents: function(),
say: function()
}
run
> hello.say()
"Hello World"
>
curl -o- https://raw.githubusercontent.com/creationix/nvm/v0.33.11/install.sh | bash
AlfreddeMacBook-Pro:blockchain alfred$ curl -o- https://raw.githubusercontent.com/creationix/nvm/v0.33.11/install.sh | bash
% Total % Received % Xferd Average Speed Time Time Time Current
Dload Upload Total Spent Left Speed
100 12819 100 12819 0 0 11138 0 0:00:01 0:00:01 --:--:-- 11146
=> Downloading nvm from git to '/Users/alfred/.nvm'
=> Cloning into '/Users/alfred/.nvm'...
remote: Counting objects: 267, done.
remote: Compressing objects: 100% (242/242), done.
remote: Total 267 (delta 31), reused 86 (delta 15), pack-reused 0
Receiving objects: 100% (267/267), 119.47 KiB | 249.00 KiB/s, done.
Resolving deltas: 100% (31/31), done.
=> Compressing and cleaning up git repository
=> Appending nvm source string to /Users/alfred/.bash_profile
=> Appending bash_completion source string to /Users/alfred/.bash_profile
=> Close and reopen your terminal to start using nvm or run the following to use it now:
export NVM_DIR="$HOME/.nvm"
[ -s "$NVM_DIR/nvm.sh" ] && \. "$NVM_DIR/nvm.sh" # This loads nvm
[ -s "$NVM_DIR/bash_completion" ] && \. "$NVM_DIR/bash_completion" # This loads nvm bash_completion
AlfreddeMacBook-Pro:blockchain alfred$
AlfreddeMacBook-Pro:blockchain alfred$ nvm install 7
Downloading and installing node v7.10.1...
Downloading https://nodejs.org/dist/v7.10.1/node-v7.10.1-darwin-x64.tar.xz...
######################################################################## 100.0%
Computing checksum with shasum -a 256
Checksums matched!
Now using node v7.10.1 (npm v4.2.0)
Creating default alias: default -> 7 (-> v7.10.1)
AlfreddeMacBook-Pro:blockchain alfred$
AlfreddeMacBook-Pro:blockchain alfred$ node --version
v7.10.1
AlfreddeMacBook-Pro:blockchain alfred$ npm --version
4.2.0
AlfreddeMacBook-Pro:blockchain alfred$ nvm --version
0.33.11
npm install remix-ide -g
Start Remix IDE
AlfreddeMacBook-Pro:blockchain alfred$ remix-ide
setup notifications for /Users/alfred/chenjingchao/blockchain
Shared folder : /Users/alfred/chenjingchao/blockchain
Starting Remix IDE at http://localhost:8080 and sharing /Users/alfred/chenjingchao/blockchain
Sat Jul 21 2018 01:20:20 GMT+0800 (CST) Remixd is listening on 127.0.0.1:65520
