feat: add support for custom update fees

target_chains/ethereum/contracts/contracts/pyth/Pyth.sol

@@ -493,8 +493,11 @@ abstract contract Pyth is
     function getTotalFee(
         uint totalNumUpdates
     ) private view returns (uint requiredFee) {
-        return
-            (totalNumUpdates * singleUpdateFeeInWei()) + transactionFeeInWei();
+        uint updateFee = customUpdateFeeInWei(msg.sender);
+        if (updateFee == 0) {
+            updateFee = singleUpdateFeeInWei();
+        }
+        return (totalNumUpdates * updateFee) + transactionFeeInWei();
     }
 
     function findIndexOfPriceId(

target_chains/ethereum/contracts/contracts/pyth/PythGetters.sol

@@ -95,4 +95,8 @@ contract PythGetters is PythState {
     function transactionFeeInWei() public view returns (uint) {
         return _state.transactionFeeInWei;
     }
+
+    function customUpdateFeeInWei(address addr) public view returns (uint) {
+        return _state.customUpdateFeeInWei[addr];
+    }
 }

target_chains/ethereum/contracts/contracts/pyth/PythGovernance.sol

@@ -39,6 +39,12 @@ abstract contract PythGovernance is
         address newWormholeAddress
     );
     event TransactionFeeSet(uint oldFee, uint newFee);
+    event CustomFeeSet(address indexed target, uint oldFee, uint newFee);
+
+    struct SetCustomFeePayload {
+        address target;
+        uint newFee;
+    }
 
     function verifyGovernanceVM(
         bytes memory encodedVM
@@ -255,4 +261,11 @@ abstract contract PythGovernance is
 
         emit TransactionFeeSet(oldFee, transactionFeeInWei());
     }
+
+    function setCustomFee(SetCustomFeePayload memory payload) internal {
+        uint oldFee = customUpdateFeeInWei(payload.target);
+        setCustomUpdateFeeInWei(payload.target, payload.newFee);
+
+        emit CustomFeeSet(payload.target, oldFee, payload.newFee);
+    }
 }

target_chains/ethereum/contracts/contracts/pyth/PythSetters.sol

@@ -5,6 +5,7 @@ pragma solidity ^0.8.0;
 
 import "./PythState.sol";
 import "@pythnetwork/pyth-sdk-solidity/IPythEvents.sol";
+import "./PythInternalStructs.sol";
 
 contract PythSetters is PythState, IPythEvents {
     function setWormhole(address wh) internal {
@@ -52,4 +53,8 @@ contract PythSetters is PythState, IPythEvents {
     function setTransactionFeeInWei(uint fee) internal {
         _state.transactionFeeInWei = fee;
     }
+
+    function setCustomUpdateFeeInWei(address addr, uint fee) internal {
+        _state.customUpdateFeeInWei[addr] = fee;
+    }
 }

target_chains/ethereum/contracts/contracts/pyth/PythState.sol

@@ -40,6 +40,8 @@ contract PythStorage {
         mapping(bytes32 => PythInternalStructs.PriceInfo) latestPriceInfo;
         // Fee charged per transaction, in addition to per-update fees
         uint transactionFeeInWei;
+        // Mapping of address to custom fee per update (0 means use default fee)
+        mapping(address => uint) customUpdateFeeInWei;
     }
 }