Refactor oracles

README.md

@@ -10,3 +10,6 @@
     User-end bundlers are provided in each chain-specific folder, instanciating all the intermediary domain-specific bundlers and associated parameters (such as chain-specific protocol addresses) as well as a [`SelfMulticall`](./contracts/bundlers/SelfMulticall.sol) that enables bundling multiple function calls into a single `multicall(uint256 deadline, bytes[] calldata data)` call to the end bundler contract.
   - [`routers/`](./contracts/routers/):
     - [`flash/`](./contracts/routers/flash/): exposes a flash loan router contract that bundles flash loans from multiple flash lenders into a single call, expecting the initiator to provide enough funds to repay every flash loan and its associated fees. The flash router contract automatically pulls tokens from the initiator at the end of the flash loan.
+  -  [`oracles/`](./contracts/oracles/): you'll find all oracles that can be used in Morpho Blue. A Morpho Blue oracle should inherit from [`BaseOracle`](./contracts/oracles/BaseOracle.sol), one collateral adapter and one borrowable adapter.
+    - [`adapters/`](./contracts/oracles/adapters/): adapters are contracts that adapt a specific oracle type (e.g. Chainlink) to one side of the market (e.g. the collateral side). Adapters should be inherited by pair (one collateral adapter and one borrowable adapter) along [`BaseOracle`](./contracts/oracles/BaseOracle.sol) to build a fully complete oracle.
+    - [`libraries/`](./contracts/oracles/libraries/): gathers all the logic to interact with a specific type of oracle.

contracts/oracles/BaseOracle.sol

@@ -0,0 +1,31 @@
+// SPDX-License-Identifier: UNLICENSED
+pragma solidity ^0.8.0;
+
+import {IOracle} from "./interfaces/IOracle.sol";
+
+import {FullMath} from "@uniswap/v3-core/libraries/FullMath.sol";
+
+abstract contract BaseOracle is IOracle {
+    using FullMath for uint256;
+
+    /// @dev The scale must be 1e36 * 10^(decimals of borrowable token - decimals of collateral token).
+    uint256 public immutable PRICE_SCALE;
+
+    // @dev The collateral price's unit.
+    uint256 public immutable COLLATERAL_SCALE;
+
+    // @dev The borrowable price's unit.
+    uint256 public immutable BORROWABLE_SCALE;
+
+    constructor(uint256 priceScale) {
+        PRICE_SCALE = priceScale;
+    }
+
+    function price() external view returns (uint256) {
+        // Using FullMath to avoid overflowing because of PRICE_SCALE.
+        return PRICE_SCALE.mulDiv(collateralPrice() * BORROWABLE_SCALE, borrowablePrice() * COLLATERAL_SCALE);
+    }
+
+    function collateralPrice() public view virtual returns (uint256);
+    function borrowablePrice() public view virtual returns (uint256);
+}

contracts/oracles/ChainlinkOracle.sol

@@ -1,26 +1,10 @@
 // SPDX-License-Identifier: UNLICENSED
 pragma solidity ^0.8.0;
 
-import {IOracle} from "./interfaces/IOracle.sol";
-import {IChainlinkAggregatorV3} from "./adapters/interfaces/IChainlinkAggregatorV3.sol";
-
-import {OracleFeed} from "./libraries/OracleFeed.sol";
-import {ChainlinkAggregatorV3Lib} from "./libraries/ChainlinkAggregatorV3Lib.sol";
-
+import {BaseOracle} from "./BaseOracle.sol";
+import {StaticBorrowableAdapter} from "./adapters/StaticBorrowableAdapter.sol";
 import {ChainlinkCollateralAdapter} from "./adapters/ChainlinkCollateralAdapter.sol";
 
-contract ChainlinkOracle is ChainlinkCollateralAdapter, IOracle {
-    using ChainlinkAggregatorV3Lib for IChainlinkAggregatorV3;
-
-    constructor(address feed) ChainlinkCollateralAdapter(feed) {}
-
-    function FEED_COLLATERAL() external view returns (string memory, address) {
-        return (OracleFeed.CHAINLINK_V3, address(CHAINLINK_COLLATERAL_FEED));
-    }
-
-    function FEED_BORROWABLE() external view returns (string memory, address) {}
-
-    function price() external view returns (uint256) {
-        return CHAINLINK_COLLATERAL_FEED.price();
-    }
+contract ChainlinkOracle is BaseOracle, ChainlinkCollateralAdapter, StaticBorrowableAdapter {
+    constructor(uint256 priceScale, address feed) BaseOracle(priceScale) ChainlinkCollateralAdapter(feed) {}
 }

contracts/oracles/ChainlinkPairOracle.sol

@@ -1,42 +1,14 @@
 // SPDX-License-Identifier: UNLICENSED
 pragma solidity ^0.8.0;
 
-import {IOracle} from "./interfaces/IOracle.sol";
-import {IChainlinkAggregatorV3} from "./adapters/interfaces/IChainlinkAggregatorV3.sol";
-
-import {OracleFeed} from "./libraries/OracleFeed.sol";
-import {FullMath} from "@uniswap/v3-core/libraries/FullMath.sol";
-import {ChainlinkAggregatorV3Lib} from "./libraries/ChainlinkAggregatorV3Lib.sol";
-
+import {BaseOracle} from "./BaseOracle.sol";
 import {ChainlinkCollateralAdapter} from "./adapters/ChainlinkCollateralAdapter.sol";
 import {ChainlinkBorrowableAdapter} from "./adapters/ChainlinkBorrowableAdapter.sol";
 
-contract ChainlinkPairOracle is ChainlinkCollateralAdapter, ChainlinkBorrowableAdapter, IOracle {
-    using ChainlinkAggregatorV3Lib for IChainlinkAggregatorV3;
-
-    /// @dev The scale must be 1e36 * 10^(decimals of borrowable token - decimals of collateral token).
-    uint256 public immutable PRICE_SCALE;
-
-    constructor(address collateralFeed, address borrowableFeed, uint256 scale)
+contract ChainlinkPairOracle is BaseOracle, ChainlinkCollateralAdapter, ChainlinkBorrowableAdapter {
+    constructor(uint256 priceScale, address collateralFeed, address borrowableFeed)
+        BaseOracle(priceScale)
         ChainlinkCollateralAdapter(collateralFeed)
         ChainlinkBorrowableAdapter(borrowableFeed)
-    {
-        PRICE_SCALE = scale;
-    }
-
-    function FEED_COLLATERAL() external view returns (string memory, address) {
-        return (OracleFeed.CHAINLINK_V3, address(CHAINLINK_COLLATERAL_FEED));
-    }
-
-    function FEED_BORROWABLE() external view returns (string memory, address) {
-        return (OracleFeed.CHAINLINK_V3, address(CHAINLINK_BORROWABLE_FEED));
-    }
-
-    function price() external view returns (uint256) {
-        return FullMath.mulDiv(
-            CHAINLINK_COLLATERAL_FEED.price() * CHAINLINK_BORROWABLE_PRICE_SCALE,
-            PRICE_SCALE, // Using FullMath to avoid overflowing because of PRICE_SCALE.
-            CHAINLINK_BORROWABLE_FEED.price() * CHAINLINK_COLLATERAL_PRICE_SCALE
-        );
-    }
+    {}
 }

contracts/oracles/ChainlinkUniswapV3Oracle.sol

@@ -1,47 +1,14 @@
 // SPDX-License-Identifier: UNLICENSED
 pragma solidity ^0.8.0;
 
-import {IOracle} from "./interfaces/IOracle.sol";
-import {IUniswapV3Pool} from "@uniswap/v3-core/interfaces/IUniswapV3Pool.sol";
-import {IChainlinkAggregatorV3} from "./adapters/interfaces/IChainlinkAggregatorV3.sol";
-
-import {OracleFeed} from "./libraries/OracleFeed.sol";
-import {WAD, MathLib} from "@morpho-blue/libraries/MathLib.sol";
-import {FullMath} from "@uniswap/v3-core/libraries/FullMath.sol";
-import {UniswapV3PoolLib} from "./libraries/UniswapV3PoolLib.sol";
-import {ChainlinkAggregatorV3Lib} from "./libraries/ChainlinkAggregatorV3Lib.sol";
-
+import {BaseOracle} from "./BaseOracle.sol";
 import {ChainlinkCollateralAdapter} from "./adapters/ChainlinkCollateralAdapter.sol";
 import {UniswapV3BorrowableAdapter} from "./adapters/UniswapV3BorrowableAdapter.sol";
 
-contract ChainlinkUniswapV3Oracle is ChainlinkCollateralAdapter, UniswapV3BorrowableAdapter, IOracle {
-    using MathLib for uint256;
-    using UniswapV3PoolLib for IUniswapV3Pool;
-    using ChainlinkAggregatorV3Lib for IChainlinkAggregatorV3;
-
-    /// @dev The scale must be 1e36 * 10^(decimals of borrowable token - decimals of collateral token).
-    uint256 public immutable PRICE_SCALE;
-
-    constructor(address feed, address pool, uint32 borrowablePriceDelay, uint256 scale)
+contract ChainlinkUniswapV3Oracle is BaseOracle, ChainlinkCollateralAdapter, UniswapV3BorrowableAdapter {
+    constructor(uint256 priceScale, address feed, address pool, uint32 borrowablePriceDelay)
+        BaseOracle(priceScale)
         ChainlinkCollateralAdapter(feed)
         UniswapV3BorrowableAdapter(pool, borrowablePriceDelay)
-    {
-        PRICE_SCALE = scale;
-    }
-
-    function FEED_COLLATERAL() external view returns (string memory, address) {
-        return (OracleFeed.CHAINLINK_V3, address(CHAINLINK_COLLATERAL_FEED));
-    }
-
-    function FEED_BORROWABLE() external view returns (string memory, address) {
-        return (OracleFeed.UNISWAP_V3, address(UNI_V3_BORROWABLE_POOL));
-    }
-
-    function price() external view returns (uint256) {
-        return FullMath.mulDiv(
-            CHAINLINK_COLLATERAL_FEED.price() * WAD,
-            PRICE_SCALE, // Using FullMath to avoid overflowing because of PRICE_SCALE.
-            UNI_V3_BORROWABLE_POOL.price(UNI_V3_BORROWABLE_DELAY) * CHAINLINK_COLLATERAL_PRICE_SCALE
-        );
-    }
+    {}
 }

contracts/oracles/UniswapV3ChainlinkOracle.sol

@@ -1,47 +1,14 @@
 // SPDX-License-Identifier: UNLICENSED
 pragma solidity ^0.8.0;
 
-import {IOracle} from "./interfaces/IOracle.sol";
-import {IUniswapV3Pool} from "@uniswap/v3-core/interfaces/IUniswapV3Pool.sol";
-import {IChainlinkAggregatorV3} from "./adapters/interfaces/IChainlinkAggregatorV3.sol";
-
-import {OracleFeed} from "./libraries/OracleFeed.sol";
-import {WAD, MathLib} from "@morpho-blue/libraries/MathLib.sol";
-import {FullMath} from "@uniswap/v3-core/libraries/FullMath.sol";
-import {UniswapV3PoolLib} from "./libraries/UniswapV3PoolLib.sol";
-import {ChainlinkAggregatorV3Lib} from "./libraries/ChainlinkAggregatorV3Lib.sol";
-
+import {BaseOracle} from "./BaseOracle.sol";
 import {UniswapV3CollateralAdapter} from "./adapters/UniswapV3CollateralAdapter.sol";
 import {ChainlinkBorrowableAdapter} from "./adapters/ChainlinkBorrowableAdapter.sol";
 
-contract UniswapV3ChainlinkOracle is UniswapV3CollateralAdapter, ChainlinkBorrowableAdapter, IOracle {
-    using MathLib for uint256;
-    using UniswapV3PoolLib for IUniswapV3Pool;
-    using ChainlinkAggregatorV3Lib for IChainlinkAggregatorV3;
-
-    /// @dev The scale must be 1e36 * 10^(decimals of borrowable token - decimals of collateral token).
-    uint256 public immutable PRICE_SCALE;
-
-    constructor(address pool, address feed, uint32 collateralPriceDelay, uint256 scale)
+contract UniswapV3ChainlinkOracle is BaseOracle, UniswapV3CollateralAdapter, ChainlinkBorrowableAdapter {
+    constructor(uint256 priceScale, address pool, address feed, uint32 collateralPriceDelay)
+        BaseOracle(priceScale)
         UniswapV3CollateralAdapter(pool, collateralPriceDelay)
         ChainlinkBorrowableAdapter(feed)
-    {
-        PRICE_SCALE = scale;
-    }
-
-    function FEED_COLLATERAL() external view returns (string memory, address) {
-        return (OracleFeed.UNISWAP_V3, address(UNI_V3_COLLATERAL_POOL));
-    }
-
-    function FEED_BORROWABLE() external view returns (string memory, address) {
-        return (OracleFeed.CHAINLINK_V3, address(CHAINLINK_BORROWABLE_FEED));
-    }
-
-    function price() external view returns (uint256) {
-        return FullMath.mulDiv(
-            UNI_V3_COLLATERAL_POOL.price(UNI_V3_COLLATERAL_DELAY) * CHAINLINK_BORROWABLE_PRICE_SCALE,
-            PRICE_SCALE, // Using FullMath to avoid overflowing because of PRICE_SCALE.
-            CHAINLINK_BORROWABLE_FEED.price() * WAD
-        );
-    }
+    {}
 }

contracts/oracles/UniswapV3Oracle.sol

@@ -1,26 +1,13 @@
 // SPDX-License-Identifier: UNLICENSED
 pragma solidity ^0.8.0;
 
-import {IOracle} from "./interfaces/IOracle.sol";
-import {IUniswapV3Pool} from "@uniswap/v3-core/interfaces/IUniswapV3Pool.sol";
-
-import {OracleFeed} from "./libraries/OracleFeed.sol";
-import {UniswapV3PoolLib} from "./libraries/UniswapV3PoolLib.sol";
-
+import {BaseOracle} from "./BaseOracle.sol";
+import {StaticBorrowableAdapter} from "./adapters/StaticBorrowableAdapter.sol";
 import {UniswapV3CollateralAdapter} from "./adapters/UniswapV3CollateralAdapter.sol";
 
-contract UniswapV3Oracle is UniswapV3CollateralAdapter, IOracle {
-    using UniswapV3PoolLib for IUniswapV3Pool;
-
-    constructor(address pool, uint32 delay) UniswapV3CollateralAdapter(pool, delay) {}
-
-    function FEED_COLLATERAL() external view returns (string memory, address) {
-        return (OracleFeed.UNISWAP_V3, address(UNI_V3_COLLATERAL_POOL));
-    }
-
-    function FEED_BORROWABLE() external view returns (string memory, address) {}
-
-    function price() external view returns (uint256) {
-        return UNI_V3_COLLATERAL_POOL.price(UNI_V3_COLLATERAL_DELAY);
-    }
+contract UniswapV3Oracle is BaseOracle, UniswapV3CollateralAdapter, StaticBorrowableAdapter {
+    constructor(uint256 priceScale, address pool, uint32 delay)
+        BaseOracle(priceScale)
+        UniswapV3CollateralAdapter(pool, delay)
+    {}
 }

contracts/oracles/UniswapV3PairOracle.sol

@@ -1,50 +1,20 @@
 // SPDX-License-Identifier: UNLICENSED
 pragma solidity ^0.8.0;
 
-import {IOracle} from "./interfaces/IOracle.sol";
-import {IUniswapV3Pool} from "@uniswap/v3-core/interfaces/IUniswapV3Pool.sol";
-
-import {OracleFeed} from "./libraries/OracleFeed.sol";
-import {MathLib} from "@morpho-blue/libraries/MathLib.sol";
-import {FullMath} from "@uniswap/v3-core/libraries/FullMath.sol";
-import {UniswapV3PoolLib} from "./libraries/UniswapV3PoolLib.sol";
-
+import {BaseOracle} from "./BaseOracle.sol";
 import {UniswapV3CollateralAdapter} from "./adapters/UniswapV3CollateralAdapter.sol";
 import {UniswapV3BorrowableAdapter} from "./adapters/UniswapV3BorrowableAdapter.sol";
 
-contract UniswapV3Oracle is UniswapV3CollateralAdapter, UniswapV3BorrowableAdapter, IOracle {
-    using MathLib for uint256;
-    using UniswapV3PoolLib for IUniswapV3Pool;
-
-    /// @dev The scale must be 1e36 * 10^(decimals of borrowable token - decimals of collateral token).
-    uint256 public immutable PRICE_SCALE;
-
+contract UniswapV3Oracle is BaseOracle, UniswapV3CollateralAdapter, UniswapV3BorrowableAdapter {
     constructor(
+        uint256 priceScale,
         address collateralPool,
         address borrowablePool,
         uint32 collateralPriceDelay,
-        uint32 borrowablePriceDelay,
-        uint256 scale
+        uint32 borrowablePriceDelay
     )
+        BaseOracle(priceScale)
         UniswapV3CollateralAdapter(collateralPool, collateralPriceDelay)
         UniswapV3BorrowableAdapter(borrowablePool, borrowablePriceDelay)
-    {
-        PRICE_SCALE = scale;
-    }
-
-    function FEED_COLLATERAL() external view returns (string memory, address) {
-        return (OracleFeed.UNISWAP_V3, address(UNI_V3_COLLATERAL_POOL));
-    }
-
-    function FEED_BORROWABLE() external view returns (string memory, address) {
-        return (OracleFeed.UNISWAP_V3, address(UNI_V3_BORROWABLE_POOL));
-    }
-
-    function price() external view returns (uint256) {
-        return FullMath.mulDiv(
-            UNI_V3_COLLATERAL_POOL.price(UNI_V3_COLLATERAL_DELAY),
-            PRICE_SCALE,
-            UNI_V3_BORROWABLE_POOL.price(UNI_V3_BORROWABLE_DELAY)
-        );
-    }
+    {}
 }

contracts/oracles/adapters/ChainlinkBorrowableAdapter.sol

@@ -3,12 +3,26 @@ pragma solidity ^0.8.0;
 
 import {IChainlinkAggregatorV3} from "./interfaces/IChainlinkAggregatorV3.sol";
 
-abstract contract ChainlinkBorrowableAdapter {
-    IChainlinkAggregatorV3 public immutable CHAINLINK_BORROWABLE_FEED;
-    uint256 public immutable CHAINLINK_BORROWABLE_PRICE_SCALE;
+import {OracleFeed} from "../libraries/OracleFeed.sol";
+import {ChainlinkAggregatorV3Lib} from "../libraries/ChainlinkAggregatorV3Lib.sol";
+
+import {BaseOracle} from "../BaseOracle.sol";
+
+abstract contract ChainlinkBorrowableAdapter is BaseOracle {
+    using ChainlinkAggregatorV3Lib for IChainlinkAggregatorV3;
+
+    IChainlinkAggregatorV3 private immutable _CHAINLINK_BORROWABLE_FEED;
 
     constructor(address feed) {
-        CHAINLINK_BORROWABLE_FEED = IChainlinkAggregatorV3(feed);
-        CHAINLINK_BORROWABLE_PRICE_SCALE = 10 ** CHAINLINK_BORROWABLE_FEED.decimals();
+        _CHAINLINK_BORROWABLE_FEED = IChainlinkAggregatorV3(feed);
+        BORROWABLE_SCALE = 10 ** _CHAINLINK_BORROWABLE_FEED.decimals();
+    }
+
+    function BORROWABLE_FEED() external view returns (string memory, address) {
+        return (OracleFeed.CHAINLINK_V3, address(_CHAINLINK_BORROWABLE_FEED));
+    }
+
+    function borrowablePrice() public view virtual override returns (uint256) {
+        return _CHAINLINK_BORROWABLE_FEED.price();
     }
 }

contracts/oracles/adapters/ChainlinkCollateralAdapter.sol

@@ -3,12 +3,26 @@ pragma solidity ^0.8.0;
 
 import {IChainlinkAggregatorV3} from "./interfaces/IChainlinkAggregatorV3.sol";
 
-abstract contract ChainlinkCollateralAdapter {
-    IChainlinkAggregatorV3 public immutable CHAINLINK_COLLATERAL_FEED;
-    uint256 public immutable CHAINLINK_COLLATERAL_PRICE_SCALE;
+import {OracleFeed} from "../libraries/OracleFeed.sol";
+import {ChainlinkAggregatorV3Lib} from "../libraries/ChainlinkAggregatorV3Lib.sol";
+
+import {BaseOracle} from "../BaseOracle.sol";
+
+abstract contract ChainlinkCollateralAdapter is BaseOracle {
+    using ChainlinkAggregatorV3Lib for IChainlinkAggregatorV3;
+
+    IChainlinkAggregatorV3 private immutable _CHAINLINK_COLLATERAL_FEED;
 
     constructor(address feed) {
-        CHAINLINK_COLLATERAL_FEED = IChainlinkAggregatorV3(feed);
-        CHAINLINK_COLLATERAL_PRICE_SCALE = 10 ** CHAINLINK_COLLATERAL_FEED.decimals();
+        _CHAINLINK_COLLATERAL_FEED = IChainlinkAggregatorV3(feed);
+        COLLATERAL_SCALE = 10 ** _CHAINLINK_COLLATERAL_FEED.decimals();
+    }
+
+    function COLLATERAL_FEED() external view returns (string memory, address) {
+        return (OracleFeed.CHAINLINK_V3, address(_CHAINLINK_COLLATERAL_FEED));
+    }
+
+    function collateralPrice() public view virtual override returns (uint256) {
+        return _CHAINLINK_COLLATERAL_FEED.price();
     }
 }

contracts/oracles/adapters/StaticBorrowableAdapter.sol

@@ -0,0 +1,20 @@
+// SPDX-License-Identifier: UNLICENSED
+pragma solidity ^0.8.0;
+
+import {OracleFeed} from "../libraries/OracleFeed.sol";
+
+import {BaseOracle} from "../BaseOracle.sol";
+
+abstract contract StaticBorrowableAdapter is BaseOracle {
+    constructor() {
+        BORROWABLE_SCALE = 1;
+    }
+
+    function BORROWABLE_FEED() external pure returns (string memory, address) {
+        return (OracleFeed.STATIC, address(0));
+    }
+
+    function borrowablePrice() public view virtual override returns (uint256) {
+        return 1;
+    }
+}