Previously we may get a floor feerate when calling `EstimateFeePerKW`
due to the fee estimator not finishing its startup process, which gives
us an empty fee map.
This is now fixed to return an error if the estimator is not started.
This commit adds a new expected field, `min_relay_feerate`, in the
response body returned from the API source, allowing the API to specify
a min relay feerate to be used instead of the FeePerKwFloor.
This change is backwards compatible as for an old API source which
doesn't specify the `min_relay_feerate`, it will be interpreted as zero.
This commit removes the interface methods `GenQueryURL` and
`ParseResponse` so the `WebAPIEstimator` can care less about the
implementation details of this interface.
This commit adds a new method `GetFeeMap` to handle querying the web API
and parse the response into a map that's used by the fee estimator. In
doing so we can provide a deeper abstraction over the `WebAPIFeeSource`
interface.
This commit was previously split into the following parts to ease
review:
- 2d746f68: replace imports
- 4008f0fd: use ecdsa.Signature
- 849e33d1: remove btcec.S256()
- b8f6ebbd: use v2 library correctly
- fa80bca9: bump go modules
In this commit, we create a new chainfee package, that houses all fee
related functionality used within the codebase. The creation of this new
package furthers our long-term goal of extracting functionality from the
bloated `lnwallet` package into new distinct packages. Additionally,
this new packages resolves a class of import cycle that could arise if a
new package that was imported by something in `lnwallet` wanted to use
the existing fee related functions in the prior `lnwallet` package.
