How to use timer in escrow

Question

I have an escrow contract where party A is sending some token to party B and right now held in escrow. I want to use the timer function in smart contract so that the token will be held for a certain period of time. After that time, the token will be reverted back to originator account, that is party A.

I am adding the escrow in an ERC20 smart contract so I can call it inside the smart contract.

How can I create a holding frame of 30 days in smart contract and after 30 days the token will be reverted back?

Answer 1

You can, for instance, have the function that creates the escrow to save the date of expiration

function createEscrow(...){
    expirationDate = now + 30 days;
    // more code for your escrow
}

The to finalize the escrow you add in your function

function endEscrow(...){
    require(expirationDate < now);
    // more code for your escrow finalization
}

If you want this to be executed automatically you can use services like ETH-Tempus, that schedule execution of contracts and is available on Rinkeby for free.

Disclaimer: I wrote the code for ETH-Tempus