Merge pull request #25 from comit-network/dynamic-liquidation

Add dynamic price-based liquidation to loan protocol

CHANGELOG.md

@@ -7,6 +7,27 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+### Added
+
+- Dynamic liquidation branch to the loan protocol:
+  - New `async fn dynamic_liquidation_transaction()` API on `Lender1`.
+    It takes a message of the form `price:timestamp` and an oracle's signature on the hash of the message, so that a _lender_ can unilaterally liquidate the loan if the `price` falls below a threshold and the `timestamp` is past a certain time.
+  - `Lender0` constructor now requires blinding key of lender address and an oracle public key.
+
+### Changed
+
+- `loan::LoanResponse` fields:
+  - Made `timelock` private, but accessible via `LoanResponse::collateral_contract(&self).timelock()`.
+  - Made `transaction` private, accessible via getter.
+  - Made `collateral_amount` private, but accessible via getter.
+- `loan::Borrower1` fields:
+  - Made `loan_transaction` private, but accessible via getter.
+  - Made `collateral_amount` private, but accessible via getter.
+- `loan::Lender1` fields:
+  - Made `timelock` private, but accessible via getter.
+- `fn liquidation_transaction()` API on `Lender1` is now `async`.
+- Model the collateral contract's timelock as a `u32`.
+
 ## [0.1.1] - 2021-07-23
 
 ## [0.1.0] - 2021-07-16

Cargo.toml

@@ -19,6 +19,7 @@ env_logger = "0.8.3"
 hex = "0.4"
 hmac = "0.10"
 log = "0.4"
+rand = "0.6"
 rust_decimal = "1"
 secp256k1 = { version = "0.20", features = [ "bitcoin_hashes", "rand" ] }
 # TODO: See if we can remove this direct dependency
@@ -30,5 +31,6 @@ thiserror = "1"
 [dev-dependencies]
 elements-harness = { git = "https://github.com/comit-network/elements-harness" }
 elements-rpc = { path = "./elements-rpc" }
+rand_chacha = "0.1"
 testcontainers = "0.12"
 tokio = { version = "1", default-features = false, features = [ "macros" ] }