ERC-20 – How to Confirm ERC20 Tokens with Ethereum Full Node?

erc-20

Sorry new to blockchain development, especially Ethereum based tokens.

So to confirm ethereum transaction you'll need a full node for ethereum.

But can the ethereum node also confirm transactions for tokens on the ethereum network. i.e. USDT, USDC, AVAx?

Best Answer

You probably shouldn't consider "confirming transactions" as an issue, it's not something you typically need to be even aware of. The node client does that automatically and it doesn't affect you much.

Token transactions are regular transactions, which get included in blocks by miners. Once a miner includes such transaction in his block and successfully mines the block, he broadcasts the block and other nodes notice that the transaction has now been mined, and consider it handled.

So it's the miners of the network who "confirm" transactions in that sense. Most nodes in the network do not mine, they just relay transactions and read data.

Centralized exchange confirmations

If you are talking about the "confirmations" counted in centralized exchanges, it's a bit different thing. That's not really a blockchain concept per se, but a thing invented by (probably) centralized exchanges.

In this context, the amount of confirmations refers to the amount of blocks on top of the block we're interested in. So if the transfer is in block 10 and the blockchain is currently at block 15, then there are 5 confirmations. The more of such confirmations there are, the more certain it is that the transaction won't be reverted anymore by chain reorganizations. Typically I guess exchanges require something like 20 confirmations with Ethereum.

In theory a transaction is never 100% certain that it won't get reverted. In theory anything after block number 0 may get reverted still, but the chances for that to happen are trivially small.

Related Solutions

[Ethereum] Minting Tokens and OnlyOwner – ERC20

If you have taken the contracts from Zeppelin Solidity, then there should be a contract called Ownable. In that contract there is a modifier called onlyOwner and the contract should look something like:

address public owner;

function Ownable() public {
   owner = msg.sender; //ownership is assigned to the address used to deploy contract

}

modifier onlyOwner {
    require(owner == msg.sender); //if msg.sender != owner, then mint function will fail to execute.
    _;
}

You will notice that onlyOwner is in the 'mint' function signature. The modifier is there to check that the msg.sender is the owner before executing any of the function's body.

[Ethereum] ERC20 tokens transactions’ history from Ethereum node

using ethersjs. This will return all transfer logs for all tokens on the network.

Under the hood it takes the signature from the event out of the ABI , which is the first element needed in the topics array (the remaining optional arguments are the indexed arguments from the event)

It then makes an RPC call for these events to the node you supplied when creating the provider.

On succesful response it parses the received hex-encoded data back to human readable data through reading the types from the ABI.

const provider = new providers.JsonRpcProvider('http...')
const event = (new Interface(StandardToken.abi)).events.Transfer
const topics = [event.topics[0]]
let logs = await provider.getLogs({
  fromBlock: 1,
  toBlock: 'latest',
  topics: topics
})

logs =  logs.map(log => event.parse(log.topics, log.data))

Best Answer

Related Solutions

[Ethereum] Minting Tokens and OnlyOwner – ERC20

[Ethereum] ERC20 tokens transactions’ history from Ethereum node

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