Open source the wrapped-tokens codebase.

@types/TransactionRawLog.d.ts

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+export interface TransactionRawLog {
+  logIndex: number;
+  transactionIndex: number;
+  transactionHash: string;
+  blockHash: string;
+  blockNumber: number;
+  address: string;
+  data: string;
+  topics: string[];
+  type: string;
+  id: string;
+}

README.md

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+# wrapped-tokens
+
+Wrapped tokens representing staked and generic assets.
+
+## Setup
+
+Requirements:
+
+- Node >= v12
+- Yarn
+
+```
+$ cd wrapped-tokens
+$ npm i -g yarn       # Install yarn if you don't already have it
+$ yarn install        # Install dependencies
+$ yarn setup          # Setup Git hooks
+```
+
+## TypeScript type definition files for the contracts
+
+To generate type definitions:
+
+```
+$ yarn compile && yarn typechain
+```
+
+## Linting and Formatting
+
+To check code for problems:
+
+```
+$ yarn typecheck      # Type-check TypeScript code
+$ yarn lint           # Check JavaScript and TypeScript code
+$ yarn lint --fix     # Fix problems where possible
+$ yarn solhint        # Check Solidity code
+$ yarn slither        # Run Slither
+```
+
+To auto-format code:
+
+```
+$ yarn fmt
+```
+
+## Testing
+
+Run all tests:
+
+```
+$ yarn test
+```
+
+To run tests in a specific file, run:
+
+```
+$ yarn test [path/to/file]
+```
+
+To run tests and generate test coverage, run:
+
+```
+$ yarn coverage
+```
+
+## Contracts
+
+[High Level Flow](./doc/weth2SmartContractsHighLevel.png)
+
+The implementation consists of 4 separate contracts, reusing
+[centre-tokens](https://github.com/centrehq/centre-tokens) audited and battle
+tested code whenever possible.
+
+- A
+  [proxy contract](https://github.com/centrehq/centre-tokens/blob/v2.1.0/contracts/v1/FiatTokenProxy.sol)
+  which is an exact duplicate of the proxy contract used be centre-tokens.
+- A token contract which for generic wrapped assets will be an exact duplicate
+  of centre-tokens
+  [fiat token](https://github.com/centrehq/centre-tokens/blob/v2.1.0/contracts/v2/FiatTokenV2_1.sol)
+  or for wrapped staked assets will be a staked token (`StakedTokenV1.sol`)
+  which inherits directly from centre-token's fiat tokens and adds exchange rate
+  functionality.
+- A mint forwarder contract (`MinterForwarder.sol`) which contains rate limited
+  minting functionality for our wrapped tokens.
+- An exchange rate updater contract (`ExchangeRateUpdater.sol`) which will only
+  be used for wrapped staked assets and contains rate limited exchange rate
+  updating functionality.
+
+### ERC20 compatible
+
+All wrapped tokens implement the ERC20 interface.
+
+### Staked Token Differences from FiatToken
+
+Wrapped staked tokens will be used to wrap staked assets. The wrapped staked
+tokens inherit from Centre's fiat token contract and add an oracle role that can
+set an exchangeRate. Both the `oracle` and the `exchangeRate` are stored in
+unstructured storage to maximize forward compatibility with future centre fiat
+token upgrades.
+
+### Rate Limited Minting
+
+The fiat token contract's built in minting has fixed minting allowances that
+when depleted require the `masterMinter` cold key to restore the mint allowance.
+We've introduced a
+minting forwarder contract that'll allow us to continously mint up to N tokens
+over M time, with the mint allowance replenishing programmatically.
+
+### Rate Limited Exchange Rate Updates
+
+Wrapped staked tokens will have a floating exchange rate that is set off-chain.
+Given the high frequency with which we'll have to update wrapped
+staked tokens exchange rates we'll utilize a seperate rate limited exchange rate
+updater contract to minimize operational load.
+
+### Ownable
+
+The contract has an Owner, who can change the `owner`, `pauser`, `blacklister`,
+`masterMinter`, or `oracle` addresses. The `owner` can not change the
+`proxyOwner` address.

contracts/test/ExchangeRateUtilTest.sol

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+/**
+ * SPDX-License-Identifier: MIT
+ *
+ * Copyright (c) 2022 Coinbase, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+pragma solidity 0.8.6;
+
+import {
+    ExchangeRateUtil
+} from "../wrapped-tokens/staking/ExchangeRateUtil.sol";
+
+contract ExchangeRateUtilTest {
+    function safeGetExchangeRate(address tokenContract)
+        external
+        view
+        returns (uint256)
+    {
+        return ExchangeRateUtil.safeGetExchangeRate(tokenContract);
+    }
+
+    function safeUpdateExchangeRate(
+        uint256 newExchangeRate,
+        address tokenContract
+    ) external {
+        ExchangeRateUtil.safeUpdateExchangeRate(newExchangeRate, tokenContract);
+    }
+}

contracts/test/MintUtilTest.sol

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+/**
+ * SPDX-License-Identifier: MIT
+ *
+ * Copyright (c) 2022 Coinbase, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+pragma solidity 0.8.6;
+
+import { MintUtil } from "../wrapped-tokens/MintUtil.sol";
+
+contract MintUtilTest {
+    function safeMint(
+        address to,
+        uint256 value,
+        address tokenContract
+    ) external {
+        MintUtil.safeMint(to, value, tokenContract);
+    }
+}

contracts/test/RateLimitTest.sol

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+/**
+ * SPDX-License-Identifier: MIT
+ *
+ * Copyright (c) 2022 Coinbase, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+pragma solidity 0.8.6;
+
+import { RateLimit } from "../wrapped-tokens/RateLimit.sol";
+
+contract RateLimitTest is RateLimit {
+    function _replenishAllowanceTest(address caller) external {
+        _replenishAllowance(caller);
+    }
+
+    function useRateLimitTest(uint256 amount) external {
+        allowances[msg.sender] = allowances[msg.sender] - amount;
+    }
+}

contracts/wrapped-tokens/FiatTokenProxy.sol

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+/**
+ * SPDX-License-Identifier: MIT
+ *
+ * Copyright (c) 2022 Coinbase, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+pragma solidity 0.6.12;
+
+import { FiatTokenProxy } from "centre-tokens/contracts/v1/FiatTokenProxy.sol";

contracts/wrapped-tokens/MintForwarder.sol

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+/**
+ * SPDX-License-Identifier: MIT
+ *
+ * Copyright (c) 2022 Coinbase, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+pragma solidity 0.8.6;
+
+import { RateLimit } from "./RateLimit.sol";
+import { MintUtil } from "./MintUtil.sol";
+
+/**
+ * @title MintForwarder
+ * @notice Forwarding contract to ERC20 tokens with mint functionality
+ */
+contract MintForwarder is RateLimit {
+    /**
+     * @dev Gets the mintable token contract address
+     * @return The address of the mintable token contract
+     */
+    address public tokenContract;
+
+    /**
+     * @dev Indicates that the contract has been initialized
+     */
+    bool internal initialized;
+
+    /**
+     * @notice Emitted on mints
+     * @param minter The address initiating the mint
+     * @param to The address the tokens are minted to
+     * @param amount The amount of tokens minted
+     */
+    event Mint(address indexed minter, address indexed to, uint256 amount);
+
+    /**
+     * @dev Function to initialize the contract
+     * @dev Can an only be called once by the deployer of the contract
+     * @dev The caller is responsible for ensuring that both the new owner and the token contract are configured correctly
+     * @param newOwner The address of the new owner of the mint contract, can either be an EOA or a contract
+     * @param newTokenContract The address of the token contract that is minted
+     */
+    function initialize(address newOwner, address newTokenContract)
+        external
+        onlyOwner
+    {
+        require(!initialized, "MintForwarder: contract is already initialized");
+        require(
+            newOwner != address(0),
+            "MintForwarder: owner is the zero address"
+        );
+        require(
+            newTokenContract != address(0),
+            "MintForwarder: tokenContract is the zero address"
+        );
+        transferOwnership(newOwner);
+        tokenContract = newTokenContract;
+        initialized = true;
+    }
+
+    /**
+     * @dev Rate limited function to mint tokens
+     * @dev The _amount must be less than or equal to the allowance of the caller
+     * @param _to The address that will receive the minted tokens
+     * @param _amount The amount of tokens to mint
+     */
+    function mint(address _to, uint256 _amount) external onlyCallers {
+        require(
+            _to != address(0),
+            "MintForwarder: cannot mint to the zero address"
+        );
+        require(_amount > 0, "MintForwarder: mint amount not greater than 0");
+
+        _replenishAllowance(msg.sender);
+
+        require(
+            _amount <= allowances[msg.sender],
+            "MintForwarder: mint amount exceeds caller allowance"
+        );
+
+        allowances[msg.sender] = allowances[msg.sender] - _amount;
+
+        MintUtil.safeMint(_to, _amount, tokenContract);
+        emit Mint(msg.sender, _to, _amount);
+    }
+}