Tasks: Support off-chain oracle queries (#82)

mimic-fi · Jul 29, 2023 · c0bef46 · c0bef46
1 parent 271cec9
commit c0bef46
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Showing 5 changed files with 253 additions and 88 deletions.
diff --git a/packages/price-oracle/test/PriceOracle.test.ts b/packages/price-oracle/test/PriceOracle.test.ts
@@ -1551,10 +1551,8 @@ describe('PriceOracle', () => {
   })
 
   describe('getPrice (off-chain)', () => {
-    let base: Contract,
-      quote: Contract,
-      feed: Contract,
-      data = '0x'
+    let data = '0x'
+    let base: Contract, quote: Contract, feed: Contract
 
     const OFF_CHAIN_ORACLE_PRICE = fp(5)
     const SMART_VAULT_ORACLE_PRICE = fp(10)

diff --git a/packages/tasks/contracts/base/BaseTask.sol b/packages/tasks/contracts/base/BaseTask.sol
@@ -147,8 +147,12 @@ abstract contract BaseTask is IBaseTask, Authorized {
      */
     function _getPrice(address base, address quote) internal view virtual returns (uint256) {
         address priceOracle = ISmartVault(smartVault).priceOracle();
-        if (priceOracle == address(0)) revert TaskSmartVaultPriceOracleNotSet(base, quote);
-        return IPriceOracle(priceOracle).getPrice(_wrappedIfNative(base), _wrappedIfNative(quote));
+        if (priceOracle == address(0)) revert TaskSmartVaultPriceOracleNotSet(smartVault);
+        bytes memory extraCallData = _decodeExtraCallData();
+        return
+            extraCallData.length == 0
+                ? IPriceOracle(priceOracle).getPrice(_wrappedIfNative(base), _wrappedIfNative(quote))
+                : IPriceOracle(priceOracle).getPrice(_wrappedIfNative(base), _wrappedIfNative(quote), extraCallData);
     }
 
     /**
@@ -172,4 +176,29 @@ abstract contract BaseTask is IBaseTask, Authorized {
     function _wrappedNativeToken() internal view returns (address) {
         return ISmartVault(smartVault).wrappedNativeToken();
     }
+
+    /**
+     * @dev Decodes any potential extra calldata stored in the calldata space. Tasks relying on the extra calldata
+     * pattern, assume that the last word of the calldata stores the extra calldata length so it can be decoded. Note
+     * that tasks relying on this pattern must contemplate this function may return bogus data if no extra calldata
+     * was given.
+     */
+    function _decodeExtraCallData() private pure returns (bytes memory data) {
+        uint256 length = uint256(_decodeLastCallDataWord());
+        if (msg.data.length < length) return new bytes(0);
+        data = new bytes(length);
+        assembly {
+            calldatacopy(add(data, 0x20), sub(sub(calldatasize(), length), 0x20), length)
+        }
+    }
+
+    /**
+     * @dev Returns the last calldata word. This function returns zero if the calldata is not long enough.
+     */
+    function _decodeLastCallDataWord() private pure returns (bytes32 result) {
+        if (msg.data.length < 36) return bytes32(0);
+        assembly {
+            result := calldataload(sub(calldatasize(), 0x20))
+        }
+    }
 }
diff --git a/packages/tasks/contracts/interfaces/base/IBaseTask.sol b/packages/tasks/contracts/interfaces/base/IBaseTask.sol
@@ -32,7 +32,7 @@ interface IBaseTask is IAuthorized {
     /**
      * @dev The smart vault's price oracle is not set
      */
-    error TaskSmartVaultPriceOracleNotSet(address base, address quote);
+    error TaskSmartVaultPriceOracleNotSet(address smartVault);
 
     /**
      * @dev Emitted every time a task is executed

diff --git a/packages/tasks/test/base/BaseTask.test.ts b/packages/tasks/test/base/BaseTask.test.ts
@@ -221,6 +221,7 @@ describe('BaseTask', () => {
 
       context('when there is not enough balance in the connector', () => {
         it('reverts', async () => {
+          // TODO: Hardhat does not decode smart vault error properly
           await expect(task.call(token, amount)).to.be.reverted
         })
       })