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Redirects in React Router v6

An important part of "routing" is handling redirects. Redirects usually happen when you want to preserve an old link and send all the traffic bound for that destination to some new URL so you don't end up with broken links.

The way we recommend handling redirects has changed in React Router v6. This document explains why.

Background

In React Router v4/5 (they have the same API, you can read about why we had to bump the major version here) we had a <Redirect> component that you could use to tell the router when to automatically redirect to another URL. You might have used it like this:

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General docs

docs

https://docs.solana.com

main github

https://github.com/solana-labs/solana

web3 sdk

https://github.com/solana-labs/solana-web3.js/

web3 api

https://solana-labs.github.io/solana-web3.js/

node rpc

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[
  {
    "className": "ARKCoin",
    "txWebUrl": "https://explorer.ark.io/transaction/",
    "feeData": {
      "fee": "10000000"
    },
    "explorers": [
      {
        "className": "ArkExplorer",

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const fs = require('fs');
const Web3 = require('web3');
const web3 = new Web3('http://localhost:8545');
const bytecode = fs.readFileSync('./build/FirstContract.bin');
const abi = JSON.parse(fs.readFileSync('./build/FirstContract.abi'));

(async function () {
  const ganacheAccounts = await web3.eth.getAccounts();
  const myWalletAddress = ganacheAccounts[0];

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const Compound = require('@compound-finance/compound-js');

const provider = 'https://mainnet.infura.io/v3/<YOUR INFURA API KEY HERE>';

const cTokenToGetCompApy = Compound.cUSDT;
const underlying = cTokenToGetCompApy.slice(1, 10);
const underlyingDecimals = Compound.decimals[underlying];
const cTokenDecimals = 8; // always 8
const comptroller = Compound.util.getAddress(Compound.Comptroller);
const opf = Compound.util.getAddress(Compound.PriceFeed);

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const Compound = require('@compound-finance/compound-js');

const provider = 'https://mainnet.infura.io/v3/' + process.env.infuraApiKey;

// mainnet
const CompoundLens = Compound.util.getAddress(Compound.CompoundLens);
const LensAbi = Compound.util.getAbi(Compound.CompoundLens);
const COMP = Compound.util.getAddress(Compound.COMP);
const Comptroller = Compound.util.getAddress(Compound.Comptroller);
const me = '0xa0df350d2637096571F7A701CBc1C5fdE30dF76A';

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// First run Ganache locally with `cUsdc` address unlocked
const Web3 = require('web3');
const web3 = new Web3('http://127.0.0.1:8545');

const usdcAbi = [{"anonymous":false,"inputs":[{"indexed":true,"internalType":"address","name":"owner","type":"address"},{"indexed":true,"internalType":"address","name":"spender","type":"address"},{"indexed":false,"internalType":"uint256","name":"value","type":"uint256"}],"name":"Approval","type":"event"},{"anonymous":false,"inputs":[{"indexed":true,"internalType":"address","name":"authorizer","type":"address"},{"indexed":true,"internalType":"bytes32","name":"nonce","type":"bytes32"}],"name":"AuthorizationCanceled","type":"event"},{"anonymous":false,"inputs":[{"indexed":true,"internalType":"address","name":"authorizer","type":"address"},{"indexed":true,"internalType":"bytes32","name":"nonce","type":"bytes32"}],"name":"AuthorizationUsed","type":"event"},{"anonymous":false,"inputs":[{"indexed":true,"internalType":"address","name":"_account","type":"address"}],"name":"Blacklist

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How do I retrieve the "COMP earned" value?

With a Smart Contract or JSON RPC

Get the value of COMP earned for an address that uses the Compound protocol. This can be done using the Lens contract with JSON RPC or another Smart Contract. If you do an eth_call with JSON RPC, it is free (no gas costs).

1. Use the getCompBalanceMetadataExt method in the Lens contract https://etherscan.io/address/0xd513d22422a3062Bd342Ae374b4b9c20E0a9a074#code
2. Lens address is posted here https://github.com/compound-finance/compound-protocol/blob/master/networks/mainnet.json#L11
3. Here is the definition https://github.com/compound-finance/compound-protocol/blob/master/contracts/Lens/CompoundLens.sol#L278

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Using the Compound API

UPDATE

The Compound cToken API now returns the values for you. See comp_borrow_apy and comp_supply_apy when requesting https://api.compound.finance/api/v2/ctoken

OLD METHOD:

1. Pick a supported cToken and its underlying asset
2. Query https://api.compound.finance/api/v2/governance/comp
3. Take the value for supplier_daily_comp or borrower_daily_comp