Including an owner address based automated routine execution in a React ethereum dapp?

Question

As I understand, all the front-end components for a react based ethereum dapp are rendered from the point of view of the user's metamask default account. All the calls to constant functions in solidity to retrieve state variable values and render the relevant components to display to users, uses the user's account.

What I would like is to add a certain design to it:

1. an automated routine running in background (with no front-end components to display) which will assess the state variable value and execute a smart contract transaction only meant to be executed by owner.

2. This owner based transaction invocation routine needs to run perpetually in the background, in an automated fashion, and not just when there is a user having your website page opened in his/her browser.

As an example, in case of the voting dapp, I want to build a routine where once a certain number of votes have been put, or a certain time limit expired, the vote calculation routine should be executed automatically, and that too from the owner's address (since only owner has the privilege of counting votes and declaring winner).

Could you please elaborate how such routine can be implemented? Would I have to store the owner's keystore file at the server end for it? is it a safe strategy? Thanks.

Answer 1

You could have a program running in the same server that serves the webpage of your app. This program will read the state of your variables and react to it executing functions. As this runs in your pc you can do the transactions using the owner keys in a safe manner.

If the trigger is solely based on time, meaning that you want the a function to be executed after a certain time has passed or in general at a particular date you can use services like AION Scheduling system. Because Aion creates an independent account (smart contract) for each user you can be sure that if the function comes from that address it correspond to a function scheduled by the owner. AION can call any function you indicate when a particular time or block has arrived.

Hope this helps

Answer 2

You need to reevaluate.

Here's the constraint. A client can't sign for an address without knowledge of the private key. Impersonation is not possible. msg.sender doesn't lie.

You need to consider the process and doing so will possibly influence the contract design.

If only the owner can declare a winner, that implies that there is a client or server out there that will eventually do so. That style implies reintroduction of centralization that often isnt necessary.

If the deadline for voting has passed and the votes are counted honestly then there would be nothing subjective for the owner to decide. It's similar for auctions and games.

Now, there might be some code to run at the conclusion. You need to think about who will run it or what triggers it. Its common to let the winner run such a function since they are incentivized to pay for gas.

Consider

function claimPrize () public onlyWinner onlyIfClosed ... 

Hope it helps.