Fee Provider
Fee Provider
Bitcoin-S has a FeeProvider that is used to fetch fee rates.
Currently, Bitcoin-s has a couple implemented, one being a BitcoindRpcClient, which will use estimateSmartFee to calculate a fee rate.
Another uses bitcoiner.live's api to get a fee rate.
Any FeeProvider can be passed to a Wallet which will be used to calculate fees for transactions when one is not specified.
HttpFeeRateProvider
A HttpFeeRateProvider is a FeeProvider that uses an outside API to get fee rates.
These can be hooked up to any website's API as long as you can provide a URI and a function to convert the response to a FeeUnit.
There also exists CachedHttpFeeRateProvider, which will cache the response for the cacheDuration as to prevent hitting request limits and save on api calls.
Checkout BitcoinerLiveFeeRateProvider's implementation for an example.