Signing once-and-for-all recurrent transactions with a wallet such as MetaMask from a backend

Question

I've been searching this for a while now but couldn't find a proper answer.

Is there any way to have users use a wallet such as MetaMask, Formatic etc. on a backend and allow the user, from the Wallet's API, to sign recurring transactions without explicitly requiring permission every time? In my use-case the need to require permission is time-sensitive and could happen at any time. It doesn't really make sense to wait for the user approval while he's working/sleeping/... for transactions that could happen multiple times a day.

I've checked MetaMask and Formatic APIs but it seems that the signing operation always have to be triggered by a user authentication/signing first (which is mostly handled by web3.js client-facing interaction)

I really don't want to store users' private keys on the server either so what could be an intermediate solution to provide users with a way to have their wallet handled by a trusting wallet provider while still allowing to delegate the rights to a third-party service?

Ideally that way i see it would be for a user to:

• connect his/her wallet once through the website
• willingly approve that during a given time-frame (or unlimited) this specific website could sign transactions on his/her behalf
• once approved, the backend could somehow sign transactions on behalf of this user

Thanks in advance

Answer 1

I don't think it's possible.But it can go like this: This can be resolved by having the user approve approval(yourAddress,max_uint) for the first time for your account to use one of its tokens, and when a third party wants to use it, it will also be through you. It's a viable solution, but I'm not sure it will meet your needs;