Asynchronous function to specify provider in truffle-config.js

[hughes-ch]

I'm working on a personal project trying to learn about web3 development, and I'm trying to set up a system where the users pay for gas using ERC20 tokens. I've found the OpenGSN project to do most of the heavy lifting and I'm trying to integrate it with truffle.

The way OpenGSN works is by wrapping the web3 provider. Then any calls to the provider is routed through their network where ETH is traded behind the scenes. It does just what I need it to, but I'm having an issue integrating the provider in truffle-config.js. From the docs, I see a custom provider can be specified:

networks: {
  live: {
    host: "178.25.19.88", // Random IP for example purposes (do not use)
    port: 80,
    network_id: 1,        // Ethereum public network
    // optional config values:
    // provider - web3 provider instance Truffle should use to talk to the Ethereum network.
    //          - function that returns a web3 provider instance (see below.)
    //          - if specified, host and port are ignored.
  }
}

From my perusing of the truffle code, it looks like the provider can be a string, function, or object. However, OpenGSN's provider wrapper is asynchronous, so it returns a Promise. Before I resolve to using a super-hack or dropping OpenGSN/truffle altogether, does anyone know if asynchronous providers are supported by truffle?