Ethereum Oraclize starter

Front-end is generated with vue-cli version 3.2.1

Basic Ethereum Oracle example including Oraclize, Truffle, Coinbase API, Web3

Demo

Get the current ETH/USD price from the Coinbase API through an Ethereum Oracle

Project setup

Install dependencies

npm install

Install Truffle (Works on the truffle version below, newer versions might get a compile error later on)

npm install -g truffle@4.1.15

Run Truffle develop (spawns a development blockchain)

truffle develop

Open a seperate terminal and run the ethereum-bridge (see package.json for what it does)

npm run bridge

Wait till it is fully loaded and you see the following message

Please add this line to your contract constructor:

OAR = OraclizeAddrResolverI(address);

Compile the contract inside the Truffle develop console

truffle(develop)> compile

Migrate the contract also inside the Truffle develop console

truffle(develop)> migrate --development --reset

Get the contract address from the ethereum-bridge terminal

Output should be something like this

    "contract_myid": "0x9fa87c542cab950bd129f3d2d13cba6199741bd1984351c04e83c54620dfee1b",
    "contract_address": "0x345ca3e014aaf5dca488057592ee47305d9b3e10"

Copy your contract address into HelloWorld.vue

let myContract = new web3.eth.Contract(
  MyContract.abi,
  //Your contract address
  "0x345ca3e014aaf5dca488057592ee47305d9b3e10"
);

Start the project

npm run serve

Enjoy!