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@critesjosh
critesjosh / signTx.js
Created Apr 2, 2021
an example script to show how to sign a Celo transaction
View signTx.js
const Web3 = require("web3")
const ContractKit = require('@celo/contractkit')
const web3 = new Web3('https://forno.celo.org')
const kit = ContractKit.newKitFromWeb3(web3)
let anAddress = '0xD86518b29BB52a5DAC5991eACf09481CE4B0710d'
async function signTx(){
let goldtoken = await kit.contracts.getGoldToken()
View api_response.json
// API call:
// https://explorer.celo.org/api?module=transaction&action=gettxinfo&txhash=0xc495463ca93ec63fa654cc12690db488a9b127221a21af4c6359ceb357f3d757
{
"status": "1",
"result": {
"value": "0",
"to": "0x6d67b41236129cb4f6ffaf6e37223485b20d1d06",
"timeStamp": "1610353070",
"success": true,
"next_page_params": null,
@critesjosh
critesjosh / cUSD_abi.json
Last active Nov 20, 2020
An example script for watching for events emitted by a Celo contract via Forno
View cUSD_abi.json
[{"type":"function","stateMutability":"view","payable":false,"outputs":[{"type":"string","name":""}],"name":"name","inputs":[],"constant":true},{"type":"function","stateMutability":"nonpayable","payable":false,"outputs":[{"type":"bool","name":""}],"name":"approve","inputs":[{"type":"address","name":"spender"},{"type":"uint256","name":"value"}],"constant":false},{"type":"function","stateMutability":"view","payable":false,"outputs":[{"type":"address","name":""}],"name":"validatorSignerAddressFromCurrentSet","inputs":[{"type":"uint256","name":"index"}],"constant":true},{"type":"function","stateMutability":"view","payable":false,"outputs":[{"type":"uint256","name":""}],"name":"valueToUnits","inputs":[{"type":"uint256","name":"value"}],"constant":true},{"type":"function","stateMutability":"view","payable":false,"outputs":[{"type":"bool","name":""}],"name":"initialized","inputs":[],"constant":true},{"type":"function","stateMutability":"view","payable":false,"outputs":[{"type":"uint256","name":""}],"name":"totalSupp
@critesjosh
critesjosh / lookup.js
Created Sep 28, 2020
A node script to run a phone number lookup with ODIS on the Celo blockchain
View lookup.js
// In this example, we will go over how to look up a Celo address that is registered with a phone number with ODIS
// 1. Import the appropriate packages
const ContractKit = require('@celo/contractkit')
const OdisUtils = require('@celo/contractkit').OdisUtils
const AuthSigner = require('@celo/contractkit/lib/identity/odis/query').AuthSigner
// 2. Import these packages to help with private key management for the example
const privateKeyToAddress = require('@celo/utils/lib/address').privateKeyToAddress
const normalizeAddressWith0x = require('@celo/utils/lib/address').normalizeAddressWith0x
@critesjosh
critesjosh / CELOtransfer.js
Created Sep 21, 2020
Celo token native transfer and ERC20 transfer using contractkit
View CELOtransfer.js
// Import ContractKit
const ContractKit = require('@celo/contractkit')
// Create a new instance of ContractKit, connecting to a local Celo node
//const contractKit = ContractKit.newKit('http://localhost:8545')
const contractKit = ContractKit.newKit('https://alfajores-forno.celo-testnet.org')
// Specify an arbitrary recipient of the transaction
const recipient = '0xB9727f7f1e1f4a5229a49E260fBBBD410d10f2Ff'
const privateKey = '3a26ebc37944c305670a21ea6a5d16c1084db2f18bc6635ba95f487e5c59868f'
@critesjosh
critesjosh / index.js
Last active May 6, 2020
This script is a demo of how to use the ContractKit to send a transaction on the Celo network (https://celo.org)
View index.js
#!/usr/bin/env node
/*
This script is a demo of how to use the ContractKit to send a transaction on the Celo network (https://celo.org)
With npm installed, run this script with the command:
npx https://gist.github.com/critesjosh/7dd9cdb3076d9d5874c061612af8057e
*/
// Import ContractKit
const ContractKit = require('@celo/contractkit')
@critesjosh
critesjosh / getInfo.js
Created Apr 9, 2020
A node.js script to print details about the Celo blockchain that is connected at http://localhost:8545
View getInfo.js
// Run this script in a npm project with contractkit installed
// https://www.npmjs.com/package/@celo/contractkit
const Kit = require('@celo/contractkit')
const CeloContract = Kit.CeloContract
const kit = Kit.newKit('http://localhost:8545')
async function wrapper(){
let accounts = await kit.web3.eth.getAccounts()
View SimpleBank.sol
/*
This exercise has been updated to use Solidity version 0.5
Breaking changes from 0.4 to 0.5 can be found here:
https://solidity.readthedocs.io/en/v0.5.0/050-breaking-changes.html
Reference Docs: https://solidity.readthedocs.io/en/latest/index.html
*/
pragma solidity ^0.5.0;
View SimpleStorage.sol
pragma solidity >=0.4.0 <0.7.0;
// Rinkeby address: 0x49Bb098E781eD5C50D85E82d85cbA1a6F03FD3e6
contract SimpleStorage {
uint storedData;
event storageUpdate(uint newValue, address updatedBy);
function set(uint x) public {
View ProjectSubmission.sol
pragma solidity ^0.5.0; // Step 1
contract ProjectSubmission { // Step 1
address owner; // Step 1 (state variable)
uint ownerBalance; // Step 4 (state variable)
modifier onlyOwner() { // Step 1
require(msg.sender == owner, "Only the owner can do this.");
_;