Hedera Token Service System Contract

Hedera enables the native creation of fungible and non-fungible tokens through its SDKs, eliminating the need for smart contracts. This approach leverages Hedera's core features like high TPS, security, and low latency for an optimized user experience. Additionally, the Hedera Token Service provides a cost-effective method for tokenization. Smart contracts on Hedera can also interact with this service via the Hedera Token Service System contract, offering functionalities like token creation, burning, and minting through the EVM.

Some of the key functions defined in the Hedera Token Service System Contract include:

Supported

https://github.com/hashgraph/hedera-smart-contracts/blob/main/contracts/hts-precompile/HederaTokenService.sol

// SPDX-License-Identifier: Apache-2.0
pragma solidity >=0.5.0 <0.9.0;
pragma experimental ABIEncoderV2;

import "./HederaResponseCodes.sol";
import "./IHederaTokenService.sol";

abstract contract HederaTokenService {
    address constant precompileAddress = address(0x167);
    // 90 days in seconds
    int32 constant defaultAutoRenewPeriod = 7776000;

    modifier nonEmptyExpiry(IHederaTokenService.HederaToken memory token)
    {
        if (token.expiry.second == 0 && token.expiry.autoRenewPeriod == 0) {
            token.expiry.autoRenewPeriod = defaultAutoRenewPeriod;
        }
        _;
    }

    /// Generic event
    event CallResponseEvent(bool, bytes);

    /// Performs transfers among combinations of tokens and hbars
    /// @param transferList the list of hbar transfers to do
    /// @param tokenTransfers the list of transfers to do
    /// @return responseCode The response code for the status of the request. SUCCESS is 22.
    /// @custom:version 0.3.0 the signature of the previous version was cryptoTransfer(TokenTransferList[] memory tokenTransfers)
    function cryptoTransfer(IHederaTokenService.TransferList memory transferList, IHederaTokenService.TokenTransferList[] memory tokenTransfers) internal
    returns (int responseCode)
    {
        (bool success, bytes memory result) = precompileAddress.call(
            abi.encodeWithSelector(IHederaTokenService.cryptoTransfer.selector, transferList, tokenTransfers));
        responseCode = success ? abi.decode(result, (int32)) : HederaResponseCodes.UNKNOWN;
    }

    /// Mints an amount of the token to the defined treasury account
    /// @param token The token for which to mint tokens. If token does not exist, transaction results in
    ///              INVALID_TOKEN_ID
    /// @param amount Applicable to tokens of type FUNGIBLE_COMMON. The amount to mint to the Treasury Account.
    ///               Amount must be a positive non-zero number represented in the lowest denomination of the
    ///               token. The new supply must be lower than 2^63.
    /// @param metadata Applicable to tokens of type NON_FUNGIBLE_UNIQUE. A list of metadata that are being created.
    ///                 Maximum allowed size of each metadata is 100 bytes
    /// @return responseCode The response code for the status of the request. SUCCESS is 22.
    /// @return newTotalSupply The new supply of tokens. For NFTs it is the total count of NFTs
    /// @return serialNumbers If the token is an NFT the newly generate serial numbers, otherwise empty.
    function mintToken(address token, int64 amount, bytes[] memory metadata) internal
    returns (int responseCode, int64 newTotalSupply, int64[] memory serialNumbers)
    {
        (bool success, bytes memory result) = precompileAddress.call(
            abi.encodeWithSelector(IHederaTokenService.mintToken.selector,
            token, amount, metadata));
        (responseCode, newTotalSupply, serialNumbers) =
        success
        ? abi.decode(result, (int32, int64, int64[]))
        : (HederaResponseCodes.UNKNOWN, int64(0), new int64[](0));
    }

    /// Burns an amount of the token from the defined treasury account
    /// @param token The token for which to burn tokens. If token does not exist, transaction results in
    ///              INVALID_TOKEN_ID
    /// @param amount  Applicable to tokens of type FUNGIBLE_COMMON. The amount to burn from the Treasury Account.
    ///                Amount must be a positive non-zero number, not bigger than the token balance of the treasury
    ///                account (0; balance], represented in the lowest denomination.
    /// @param serialNumbers Applicable to tokens of type NON_FUNGIBLE_UNIQUE. The list of serial numbers to be burned.
    /// @return responseCode The response code for the status of the request. SUCCESS is 22.
    /// @return newTotalSupply The new supply of tokens. For NFTs it is the total count of NFTs
    function burnToken(address token, int64 amount, int64[] memory serialNumbers) internal
    returns (int responseCode, int64 newTotalSupply)
    {
        (bool success, bytes memory result) = precompileAddress.call(
            abi.encodeWithSelector(IHederaTokenService.burnToken.selector,
            token, amount, serialNumbers));
        (responseCode, newTotalSupply) =
        success
        ? abi.decode(result, (int32, int64))
        : (HederaResponseCodes.UNKNOWN, int64(0));
    }

    ///  Associates the provided account with the provided tokens. Must be signed by the provided
    ///  Account's key or called from the accounts contract key
    ///  If the provided account is not found, the transaction will resolve to INVALID_ACCOUNT_ID.
    ///  If the provided account has been deleted, the transaction will resolve to ACCOUNT_DELETED.
    ///  If any of the provided tokens is not found, the transaction will resolve to INVALID_TOKEN_REF.
    ///  If any of the provided tokens has been deleted, the transaction will resolve to TOKEN_WAS_DELETED.
    ///  If an association between the provided account and any of the tokens already exists, the
    ///  transaction will resolve to TOKEN_ALREADY_ASSOCIATED_TO_ACCOUNT.
    ///  If the provided account's associations count exceed the constraint of maximum token associations
    ///    per account, the transaction will resolve to TOKENS_PER_ACCOUNT_LIMIT_EXCEEDED.
    ///  On success, associations between the provided account and tokens are made and the account is
    ///    ready to interact with the tokens.
    /// @param account The account to be associated with the provided tokens
    /// @param tokens The tokens to be associated with the provided account. In the case of NON_FUNGIBLE_UNIQUE
    ///               Type, once an account is associated, it can hold any number of NFTs (serial numbers) of that
    ///               token type
    /// @return responseCode The response code for the status of the request. SUCCESS is 22.
    function associateTokens(address account, address[] memory tokens) internal returns (int responseCode) {
        (bool success, bytes memory result) = precompileAddress.call(
            abi.encodeWithSelector(IHederaTokenService.associateTokens.selector,
            account, tokens));
        responseCode = success ? abi.decode(result, (int32)) : HederaResponseCodes.UNKNOWN;
    }

    function associateToken(address account, address token) internal returns (int responseCode) {
        (bool success, bytes memory result) = precompileAddress.call(
            abi.encodeWithSelector(IHederaTokenService.associateToken.selector,
            account, token));
        responseCode = success ? abi.decode(result, (int32)) : HederaResponseCodes.UNKNOWN;
    }

    /// Dissociates the provided account with the provided tokens. Must be signed by the provided
    /// Account's key.
    /// If the provided account is not found, the transaction will resolve to INVALID_ACCOUNT_ID.
    /// If the provided account has been deleted, the transaction will resolve to ACCOUNT_DELETED.
    /// If any of the provided tokens is not found, the transaction will resolve to INVALID_TOKEN_REF.
    /// If any of the provided tokens has been deleted, the transaction will resolve to TOKEN_WAS_DELETED.
    /// If an association between the provided account and any of the tokens does not exist, the
    /// transaction will resolve to TOKEN_NOT_ASSOCIATED_TO_ACCOUNT.
    /// If a token has not been deleted and has not expired, and the user has a nonzero balance, the
    /// transaction will resolve to TRANSACTION_REQUIRES_ZERO_TOKEN_BALANCES.
    /// If a <b>fungible token</b> has expired, the user can disassociate even if their token balance is
    /// not zero.
    /// If a <b>non fungible token</b> has expired, the user can <b>not</b> disassociate if their token
    /// balance is not zero. The transaction will resolve to TRANSACTION_REQUIRED_ZERO_TOKEN_BALANCES.
    /// On success, associations between the provided account and tokens are removed.
    /// @param account The account to be dissociated from the provided tokens
    /// @param tokens The tokens to be dissociated from the provided account.
    /// @return responseCode The response code for the status of the request. SUCCESS is 22.
    function dissociateTokens(address account, address[] memory tokens) internal returns (int responseCode) {
        (bool success, bytes memory result) = precompileAddress.call(
            abi.encodeWithSelector(IHederaTokenService.dissociateTokens.selector,
            account, tokens));
        responseCode = success ? abi.decode(result, (int32)) : HederaResponseCodes.UNKNOWN;
    }

    function dissociateToken(address account, address token) internal returns (int responseCode) {
        (bool success, bytes memory result) = precompileAddress.call(
            abi.encodeWithSelector(IHederaTokenService.dissociateToken.selector,
            account, token));
        responseCode = success ? abi.decode(result, (int32)) : HederaResponseCodes.UNKNOWN;
    }

    /// Creates a Fungible Token with the specified properties
    /// @param token the basic properties of the token being created
    /// @param initialTotalSupply Specifies the initial supply of tokens to be put in circulation. The
    /// initial supply is sent to the Treasury Account. The supply is in the lowest denomination possible.
    /// @param decimals the number of decimal places a token is divisible by
    /// @return responseCode The response code for the status of the request. SUCCESS is 22.
    /// @return tokenAddress the created token's address
    function createFungibleToken(
        IHederaTokenService.HederaToken memory token,
        int64 initialTotalSupply,
        int32 decimals) nonEmptyExpiry(token)
    internal returns (int responseCode, address tokenAddress) {
        (bool success, bytes memory result) = precompileAddress.call{value : msg.value}(
            abi.encodeWithSelector(IHederaTokenService.createFungibleToken.selector,
            token, initialTotalSupply, decimals));


        (responseCode, tokenAddress) = success ? abi.decode(result, (int32, address)) : (HederaResponseCodes.UNKNOWN, address(0));
    }

    /// Creates a Fungible Token with the specified properties
    /// @param token the basic properties of the token being created
    /// @param initialTotalSupply Specifies the initial supply of tokens to be put in circulation. The
    /// initial supply is sent to the Treasury Account. The supply is in the lowest denomination possible.
    /// @param decimals the number of decimal places a token is divisible by
    /// @param fixedFees list of fixed fees to apply to the token
    /// @param fractionalFees list of fractional fees to apply to the token
    /// @return responseCode The response code for the status of the request. SUCCESS is 22.
    /// @return tokenAddress the created token's address
    function createFungibleTokenWithCustomFees(
        IHederaTokenService.HederaToken memory token,
        int64 initialTotalSupply,
        int32 decimals,
        IHederaTokenService.FixedFee[] memory fixedFees,
        IHederaTokenService.FractionalFee[] memory fractionalFees) nonEmptyExpiry(token)
    internal returns (int responseCode, address tokenAddress) {
        (bool success, bytes memory result) = precompileAddress.call{value : msg.value}(
            abi.encodeWithSelector(IHederaTokenService.createFungibleTokenWithCustomFees.selector,
            token, initialTotalSupply, decimals, fixedFees, fractionalFees));
        (responseCode, tokenAddress) = success ? abi.decode(result, (int32, address)) : (HederaResponseCodes.UNKNOWN, address(0));
    }

    /// Creates an Non Fungible Unique Token with the specified properties
    /// @param token the basic properties of the token being created
    /// @return responseCode The response code for the status of the request. SUCCESS is 22.
    /// @return tokenAddress the created token's address
    function createNonFungibleToken(IHederaTokenService.HederaToken memory token) nonEmptyExpiry(token)
    internal returns (int responseCode, address tokenAddress) {
        (bool success, bytes memory result) = precompileAddress.call{value : msg.value}(
            abi.encodeWithSelector(IHederaTokenService.createNonFungibleToken.selector, token));
        (responseCode, tokenAddress) = success ? abi.decode(result, (int32, address)) : (HederaResponseCodes.UNKNOWN, address(0));
    }

    /// Creates an Non Fungible Unique Token with the specified properties
    /// @param token the basic properties of the token being created
    /// @param fixedFees list of fixed fees to apply to the token
    /// @param royaltyFees list of royalty fees to apply to the token
    /// @return responseCode The response code for the status of the request. SUCCESS is 22.
    /// @return tokenAddress the created token's address
    function createNonFungibleTokenWithCustomFees(
        IHederaTokenService.HederaToken memory token,
        IHederaTokenService.FixedFee[] memory fixedFees,
        IHederaTokenService.RoyaltyFee[] memory royaltyFees) nonEmptyExpiry(token)
    internal returns (int responseCode, address tokenAddress) {
        (bool success, bytes memory result) = precompileAddress.call{value : msg.value}(
            abi.encodeWithSelector(IHederaTokenService.createNonFungibleTokenWithCustomFees.selector,
            token, fixedFees, royaltyFees));
        (responseCode, tokenAddress) = success ? abi.decode(result, (int32, address)) : (HederaResponseCodes.UNKNOWN, address(0));
    }

    /// Retrieves fungible specific token info for a fungible token
    /// @param token The ID of the token as a solidity address
    function getFungibleTokenInfo(address token) internal returns (int responseCode, IHederaTokenService.FungibleTokenInfo memory tokenInfo) {
        (bool success, bytes memory result) = precompileAddress.call(
            abi.encodeWithSelector(IHederaTokenService.getFungibleTokenInfo.selector, token));
        IHederaTokenService.FungibleTokenInfo memory defaultTokenInfo;
        (responseCode, tokenInfo) = success ? abi.decode(result, (int32, IHederaTokenService.FungibleTokenInfo)) : (HederaResponseCodes.UNKNOWN, defaultTokenInfo);
    }

    /// Retrieves general token info for a given token
    /// @param token The ID of the token as a solidity address
    function getTokenInfo(address token) internal returns (int responseCode, IHederaTokenService.TokenInfo memory tokenInfo) {
        (bool success, bytes memory result) = precompileAddress.call(
            abi.encodeWithSelector(IHederaTokenService.getTokenInfo.selector, token));
        IHederaTokenService.TokenInfo memory defaultTokenInfo;
        (responseCode, tokenInfo) = success ? abi.decode(result, (int32, IHederaTokenService.TokenInfo)) : (HederaResponseCodes.UNKNOWN, defaultTokenInfo);
    }

    /// Retrieves non-fungible specific token info for a given NFT
    /// @param token The ID of the token as a solidity address
    function getNonFungibleTokenInfo(address token, int64 serialNumber) internal returns (int responseCode, IHederaTokenService.NonFungibleTokenInfo memory tokenInfo) {
        (bool success, bytes memory result) = precompileAddress.call(
            abi.encodeWithSelector(IHederaTokenService.getNonFungibleTokenInfo.selector, token, serialNumber));
        IHederaTokenService.NonFungibleTokenInfo memory defaultTokenInfo;
        (responseCode, tokenInfo) = success ? abi.decode(result, (int32, IHederaTokenService.NonFungibleTokenInfo)) : (HederaResponseCodes.UNKNOWN, defaultTokenInfo);
    }

    /// Query token custom fees
    /// @param token The token address to check
    /// @return responseCode The response code for the status of the request. SUCCESS is 22.
    /// @return fixedFees Set of fixed fees for `token`
    /// @return fractionalFees Set of fractional fees for `token`
    /// @return royaltyFees Set of royalty fees for `token`
    function getTokenCustomFees(address token) internal returns (int64 responseCode,
        IHederaTokenService.FixedFee[] memory fixedFees,
        IHederaTokenService.FractionalFee[] memory fractionalFees,
        IHederaTokenService.RoyaltyFee[] memory royaltyFees) {
        (bool success, bytes memory result) = precompileAddress.call(
            abi.encodeWithSelector(IHederaTokenService.getTokenCustomFees.selector, token));
        IHederaTokenService.FixedFee[] memory defaultFixedFees;
        IHederaTokenService.FractionalFee[] memory defaultFractionalFees;
        IHederaTokenService.RoyaltyFee[] memory defaultRoyaltyFees;
        (responseCode, fixedFees, fractionalFees, royaltyFees) =
        success ? abi.decode
        (result, (int32, IHederaTokenService.FixedFee[], IHederaTokenService.FractionalFee[], IHederaTokenService.RoyaltyFee[]))
        : (HederaResponseCodes.UNKNOWN, defaultFixedFees, defaultFractionalFees, defaultRoyaltyFees);
    }

    /// Allows spender to withdraw from your account multiple times, up to the value amount. If this function is called
    /// again it overwrites the current allowance with value.
    /// Only Applicable to Fungible Tokens
    /// @param token The hedera token address to approve
    /// @param spender the account authorized to spend
    /// @param amount the amount of tokens authorized to spend.
    /// @return responseCode The response code for the status of the request. SUCCESS is 22.
    function approve(address token, address spender, uint256 amount) internal returns (int responseCode)
    {
        (bool success, bytes memory result) = precompileAddress.call(
            abi.encodeWithSelector(IHederaTokenService.approve.selector,
            token, spender, amount));
        responseCode = success ? abi.decode(result, (int32)) : HederaResponseCodes.UNKNOWN;
    }

    /// Transfers `amount` tokens from `from` to `to` using the
    //  allowance mechanism. `amount` is then deducted from the caller's allowance.
    /// Only applicable to fungible tokens
    /// @param token The address of the fungible Hedera token to transfer
    /// @param from The account address of the owner of the token, on the behalf of which to transfer `amount` tokens
    /// @param to The account address of the receiver of the `amount` tokens
    /// @param amount The amount of tokens to transfer from `from` to `to`
    /// @return responseCode The response code for the status of the request. SUCCESS is 22.
    function transferFrom(address token, address from, address to, uint256 amount) external returns (int64 responseCode)
    {
        (bool success, bytes memory result) = precompileAddress.call(
            abi.encodeWithSelector(IHederaTokenService.transferFrom.selector,
            token, from, to, amount));
        responseCode = success ? abi.decode(result, (int32)) : HederaResponseCodes.UNKNOWN;
    }

    /// Transfers `serialNumber` of `token` from `from` to `to` using the allowance mechanism.
    /// Only applicable to NFT tokens
    /// @param token The address of the non-fungible Hedera token to transfer
    /// @param from The account address of the owner of `serialNumber` of `token`
    /// @param to The account address of the receiver of `serialNumber`
    /// @param serialNumber The NFT serial number to transfer
    /// @return responseCode The response code for the status of the request. SUCCESS is 22.
    function transferFromNFT(address token, address from, address to, uint256 serialNumber) external returns (int64 responseCode)
    {
        (bool success, bytes memory result) = precompileAddress.call(
            abi.encodeWithSelector(IHederaTokenService.transferFromNFT.selector,
            token, from, to, serialNumber));
        responseCode = success ? abi.decode(result, (int32)) : HederaResponseCodes.UNKNOWN;
    }

    /// Returns the amount which spender is still allowed to withdraw from owner.
    /// Only Applicable to Fungible Tokens
    /// @param token The Hedera token address to check the allowance of
    /// @param owner the owner of the tokens to be spent
    /// @param spender the spender of the tokens
    /// @return responseCode The response code for the status of the request. SUCCESS is 22.
    function allowance(address token, address owner, address spender) internal returns (int responseCode, uint256 amount)
    {
        (bool success, bytes memory result) = precompileAddress.call(
            abi.encodeWithSelector(IHederaTokenService.allowance.selector,
            token, owner, spender));
        (responseCode, amount) = success ? abi.decode(result, (int32, uint256)) : (HederaResponseCodes.UNKNOWN, 0);
    }

    /// Allow or reaffirm the approved address to transfer an NFT the approved address does not own.
    /// Only Applicable to NFT Tokens
    /// @param token The Hedera NFT token address to approve
    /// @param approved The new approved NFT controller.  To revoke approvals pass in the zero address.
    /// @param serialNumber The NFT serial number  to approve
    /// @return responseCode The response code for the status of the request. SUCCESS is 22.
    function approveNFT(address token, address approved, uint256 serialNumber) internal returns (int responseCode)
    {
        (bool success, bytes memory result) = precompileAddress.call(
            abi.encodeWithSelector(IHederaTokenService.approveNFT.selector,
            token, approved, serialNumber));
        responseCode = success ? abi.decode(result, (int32)) : HederaResponseCodes.UNKNOWN;
    }

    /// Get the approved address for a single NFT
    /// Only Applicable to NFT Tokens
    /// @param token The Hedera NFT token address to check approval
    /// @param serialNumber The NFT to find the approved address for
    /// @return responseCode The response code for the status of the request. SUCCESS is 22.
    /// @return approved The approved address for this NFT, or the zero address if there is none
    function getApproved(address token, uint256 serialNumber) internal returns (int responseCode, address approved)
    {
        (bool success, bytes memory result) = precompileAddress.call(
            abi.encodeWithSelector(IHederaTokenService.getApproved.selector,
            token, serialNumber));
        (responseCode, approved) =
        success
        ? abi.decode(result, (int32, address))
        : (HederaResponseCodes.UNKNOWN, address(0));
    }

    /// Query if token account is frozen
    /// @param token The token address to check
    /// @param account The account address associated with the token
    /// @return responseCode The response code for the status of the request. SUCCESS is 22.
    /// @return frozen True if `account` is frozen for `token`
    function isFrozen(address token, address account) internal returns (int64 responseCode, bool frozen){
        (bool success, bytes memory result) = precompileAddress.call(
            abi.encodeWithSelector(IHederaTokenService.isFrozen.selector, token, account));
        (responseCode, frozen) = success ? abi.decode(result, (int32, bool)) : (HederaResponseCodes.UNKNOWN, false);
    }

    /// Query if token account has kyc granted
    /// @param token The token address to check
    /// @param account The account address associated with the token
    /// @return responseCode The response code for the status of the request. SUCCESS is 22.
    /// @return kycGranted True if `account` has kyc granted for `token`
    function isKyc(address token, address account) internal returns (int64 responseCode, bool kycGranted){
        (bool success, bytes memory result) = precompileAddress.call(
            abi.encodeWithSelector(IHederaTokenService.isKyc.selector, token, account));
        (responseCode, kycGranted) = success ? abi.decode(result, (int32, bool)) : (HederaResponseCodes.UNKNOWN, false);
    }

    /// Operation to freeze token account
    /// @param token The token address
    /// @param account The account address to be frozen
    /// @return responseCode The response code for the status of the request. SUCCESS is 22.
    function freezeToken(address token, address account) internal returns (int64 responseCode){
        (bool success, bytes memory result) = precompileAddress.call(
            abi.encodeWithSelector(IHederaTokenService.freezeToken.selector, token, account));
        (responseCode) = success ? abi.decode(result, (int32)) : HederaResponseCodes.UNKNOWN;
    }

    /// Operation to unfreeze token account
    /// @param token The token address
    /// @param account The account address to be unfrozen
    /// @return responseCode The response code for the status of the request. SUCCESS is 22.
    function unfreezeToken(address token, address account) internal returns (int64 responseCode){
        (bool success, bytes memory result) = precompileAddress.call(
            abi.encodeWithSelector(IHederaTokenService.unfreezeToken.selector, token, account));
        (responseCode) = success ? abi.decode(result, (int32)) : HederaResponseCodes.UNKNOWN;
    }

    /// Operation to grant kyc to token account
    /// @param token The token address
    /// @param account The account address to grant kyc
    /// @return responseCode The response code for the status of the request. SUCCESS is 22.
    function grantTokenKyc(address token, address account) internal returns (int64 responseCode){
        (bool success, bytes memory result) = precompileAddress.call(
            abi.encodeWithSelector(IHederaTokenService.grantTokenKyc.selector, token, account));
        (responseCode) = success ? abi.decode(result, (int32)) : HederaResponseCodes.UNKNOWN;
    }

    /// Operation to revoke kyc to token account
    /// @param token The token address
    /// @param account The account address to revoke kyc
    /// @return responseCode The response code for the status of the request. SUCCESS is 22.
    function revokeTokenKyc(address token, address account) internal returns (int64 responseCode){
        (bool success, bytes memory result) = precompileAddress.call(
            abi.encodeWithSelector(IHederaTokenService.revokeTokenKyc.selector, token, account));
        (responseCode) = success ? abi.decode(result, (int32)) : HederaResponseCodes.UNKNOWN;
    }

    /// Enable or disable approval for a third party ("operator") to manage
    ///  all of `msg.sender`'s assets
    /// @param token The Hedera NFT token address to approve
    /// @param operator Address to add to the set of authorized operators
    /// @param approved True if the operator is approved, false to revoke approval
    /// @return responseCode The response code for the status of the request. SUCCESS is 22.
    function setApprovalForAll(address token, address operator, bool approved) internal returns (int responseCode)
    {
        (bool success, bytes memory result) = precompileAddress.call(
            abi.encodeWithSelector(IHederaTokenService.setApprovalForAll.selector,
            token, operator, approved));
        responseCode = success ? abi.decode(result, (int32)) : HederaResponseCodes.UNKNOWN;
    }

    /// Query if an address is an authorized operator for another address
    /// Only Applicable to NFT Tokens
    /// @param token The Hedera NFT token address to approve
    /// @param owner The address that owns the NFTs
    /// @param operator The address that acts on behalf of the owner
    /// @return responseCode The response code for the status of the request. SUCCESS is 22.
    /// @return approved True if `operator` is an approved operator for `owner`, false otherwise
    function isApprovedForAll(address token, address owner, address operator) internal returns (int responseCode, bool approved)
    {
        (bool success, bytes memory result) = precompileAddress.call(
            abi.encodeWithSelector(IHederaTokenService.isApprovedForAll.selector,
            token, owner, operator));
        (responseCode, approved) =
        success
        ? abi.decode(result, (int32, bool))
        : (HederaResponseCodes.UNKNOWN, false);
    }

    /// Query token default freeze status
    /// @param token The token address to check
    /// @return responseCode The response code for the status of the request. SUCCESS is 22.
    /// @return defaultFreezeStatus True if `token` default freeze status is frozen.
    function getTokenDefaultFreezeStatus(address token) internal returns (int responseCode, bool defaultFreezeStatus) {
        (bool success, bytes memory result) = precompileAddress.call(
            abi.encodeWithSelector(IHederaTokenService.getTokenDefaultFreezeStatus.selector, token));
        (responseCode, defaultFreezeStatus) = success ? abi.decode(result, (int32, bool)) : (HederaResponseCodes.UNKNOWN, false);
    }

    /// Query token default kyc status
    /// @param token The token address to check
    /// @return responseCode The response code for the status of the request. SUCCESS is 22.
    /// @return defaultKycStatus True if `token` default kyc status is KycNotApplicable and false if Revoked.
    function getTokenDefaultKycStatus(address token) internal returns (int responseCode, bool defaultKycStatus) {
        (bool success, bytes memory result) = precompileAddress.call(
            abi.encodeWithSelector(IHederaTokenService.getTokenDefaultKycStatus.selector, token));
        (responseCode, defaultKycStatus) = success ? abi.decode(result, (int32, bool)) : (HederaResponseCodes.UNKNOWN, false);
    }

    /**********************
     * ABI v1 calls       *
     **********************/

    /// Initiates a Fungible Token Transfer
    /// @param token The ID of the token as a solidity address
    /// @param accountIds account to do a transfer to/from
    /// @param amounts The amount from the accountId at the same index
    function transferTokens(address token, address[] memory accountIds, int64[] memory amounts) internal
    returns (int responseCode)
    {
        (bool success, bytes memory result) = precompileAddress.call(
            abi.encodeWithSelector(IHederaTokenService.transferTokens.selector,
            token, accountIds, amounts));
        responseCode = success ? abi.decode(result, (int32)) : HederaResponseCodes.UNKNOWN;
    }

    /// Initiates a Non-Fungable Token Transfer
    /// @param token The ID of the token as a solidity address
    /// @param sender the sender of an nft
    /// @param receiver the receiver of the nft sent by the same index at sender
    /// @param serialNumber the serial number of the nft sent by the same index at sender
    function transferNFTs(address token, address[] memory sender, address[] memory receiver, int64[] memory serialNumber)
    internal returns (int responseCode)
    {
        (bool success, bytes memory result) = precompileAddress.call(
            abi.encodeWithSelector(IHederaTokenService.transferNFTs.selector,
            token, sender, receiver, serialNumber));
        responseCode = success ? abi.decode(result, (int32)) : HederaResponseCodes.UNKNOWN;
    }

    /// Transfers tokens where the calling account/contract is implicitly the first entry in the token transfer list,
    /// where the amount is the value needed to zero balance the transfers. Regular signing rules apply for sending
    /// (positive amount) or receiving (negative amount)
    /// @param token The token to transfer to/from
    /// @param sender The sender for the transaction
    /// @param receiver The receiver of the transaction
    /// @param amount Non-negative value to send. a negative value will result in a failure.
    function transferToken(address token, address sender, address receiver, int64 amount) internal
    returns (int responseCode)
    {
        (bool success, bytes memory result) = precompileAddress.call(
            abi.encodeWithSelector(IHederaTokenService.transferToken.selector,
            token, sender, receiver, amount));
        responseCode = success ? abi.decode(result, (int32)) : HederaResponseCodes.UNKNOWN;
    }

    /// Transfers tokens where the calling account/contract is implicitly the first entry in the token transfer list,
    /// where the amount is the value needed to zero balance the transfers. Regular signing rules apply for sending
    /// (positive amount) or receiving (negative amount)
    /// @param token The token to transfer to/from
    /// @param sender The sender for the transaction
    /// @param receiver The receiver of the transaction
    /// @param serialNumber The serial number of the NFT to transfer.
    function transferNFT(address token, address sender, address receiver, int64 serialNumber) internal
    returns (int responseCode)
    {
        (bool success, bytes memory result) = precompileAddress.call(
            abi.encodeWithSelector(IHederaTokenService.transferNFT.selector,
            token, sender, receiver, serialNumber));
        responseCode = success ? abi.decode(result, (int32)) : HederaResponseCodes.UNKNOWN;
    }

    /// Operation to pause token
    /// @param token The token address to be paused
    /// @return responseCode The response code for the status of the request. SUCCESS is 22.
    function pauseToken(address token) internal returns (int responseCode)
    {
        (bool success, bytes memory result) = precompileAddress.call(
            abi.encodeWithSelector(IHederaTokenService.pauseToken.selector, token));
        (responseCode) = success ? abi.decode(result, (int32)) : HederaResponseCodes.UNKNOWN;
    }

    /// Operation to unpause token
    /// @param token The token address to be unpaused
    /// @return responseCode The response code for the status of the request. SUCCESS is 22.
    function unpauseToken(address token) internal returns (int responseCode)
    {
        (bool success, bytes memory result) = precompileAddress.call(
            abi.encodeWithSelector(IHederaTokenService.unpauseToken.selector, token));
        (responseCode) = success ? abi.decode(result, (int32)) : HederaResponseCodes.UNKNOWN;
    }

    /// Operation to wipe fungible tokens from account
    /// @param token The token address
    /// @param account The account address to revoke kyc
    /// @param amount The number of tokens to wipe
    /// @return responseCode The response code for the status of the request. SUCCESS is 22.
    function wipeTokenAccount(address token, address account, int64 amount) internal returns (int responseCode)
    {
        (bool success, bytes memory result) = precompileAddress.call(
            abi.encodeWithSelector(IHederaTokenService.wipeTokenAccount.selector, token, account, amount));
        (responseCode) = success ? abi.decode(result, (int32)) : HederaResponseCodes.UNKNOWN;
    }

    /// Operation to wipe non fungible tokens from account
    /// @param token The token address
    /// @param account The account address to revoke kyc
    /// @param  serialNumbers The serial numbers of token to wipe
    /// @return responseCode The response code for the status of the request. SUCCESS is 22.
    function wipeTokenAccountNFT(address token, address account, int64[] memory serialNumbers) internal
    returns (int responseCode)
    {
        (bool success, bytes memory result) = precompileAddress.call(
            abi.encodeWithSelector(IHederaTokenService.wipeTokenAccountNFT.selector, token, account, serialNumbers));
        (responseCode) = success ? abi.decode(result, (int32)) : HederaResponseCodes.UNKNOWN;
    }

    /// Operation to delete token
    /// @param token The token address
    /// @return responseCode The response code for the status of the request. SUCCESS is 22.
    function deleteToken(address token) internal returns (int responseCode)
    {
        (bool success, bytes memory result) = precompileAddress.call(
            abi.encodeWithSelector(IHederaTokenService.deleteToken.selector, token));
        (responseCode) = success ? abi.decode(result, (int32)) : HederaResponseCodes.UNKNOWN;
    }

    /// Operation to update token keys
    /// @param token The token address
    /// @param keys The token keys
    /// @return responseCode The response code for the status of the request. SUCCESS is 22.
    function updateTokenKeys(address token, IHederaTokenService.TokenKey[] memory keys)
    internal returns (int64 responseCode){
        (bool success, bytes memory result) = precompileAddress.call(
            abi.encodeWithSelector(IHederaTokenService.updateTokenKeys.selector, token, keys));
        (responseCode) = success ? abi.decode(result, (int32)) : HederaResponseCodes.UNKNOWN;
    }

    /// Query token KeyValue
    /// @param token The token address to check
    /// @param keyType The keyType of the desired KeyValue
    /// @return responseCode The response code for the status of the request. SUCCESS is 22.
    /// @return key KeyValue info for key of type `keyType`
    function getTokenKey(address token, uint keyType)
    internal returns (int64 responseCode, IHederaTokenService.KeyValue memory key){
        (bool success, bytes memory result) = precompileAddress.call(
            abi.encodeWithSelector(IHederaTokenService.getTokenKey.selector, token, keyType));
        IHederaTokenService.KeyValue memory defaultKeyValueInfo;
        (responseCode, key) = success ? abi.decode(result, (int32,IHederaTokenService.KeyValue) ) : (HederaResponseCodes.UNKNOWN, defaultKeyValueInfo);
    }


    /// Query if valid token found for the given address
    /// @param token The token address
    /// @return responseCode The response code for the status of the request. SUCCESS is 22.
    /// @return isTokenFlag True if valid token found for the given address
    function isToken(address token) internal returns (int64 responseCode, bool isTokenFlag) {
        (bool success, bytes memory result) = precompileAddress.call(
            abi.encodeWithSelector(IHederaTokenService.isToken.selector, token));
        (responseCode, isTokenFlag) = success ? abi.decode(result, (int32, bool)) : (HederaResponseCodes.UNKNOWN, false);
    }

    /// Query to return the token type for a given address
    /// @param token The token address
    /// @return responseCode The response code for the status of the request. SUCCESS is 22.
    /// @return tokenType the token type. 0 is FUNGIBLE_COMMON, 1 is NON_FUNGIBLE_UNIQUE, -1 is UNRECOGNIZED
    function getTokenType(address token) internal returns (int64 responseCode, int32 tokenType) {
        (bool success, bytes memory result) = precompileAddress.call(
            abi.encodeWithSelector(IHederaTokenService.getTokenType.selector, token));
        (responseCode, tokenType) = success ? abi.decode(result, (int32, int32)) : (HederaResponseCodes.UNKNOWN, - 1);
    }

    /// Operation to get token expiry info
    /// @param token The token address
    /// @return responseCode The response code for the status of the request. SUCCESS is 22.
    /// @return expiryInfo The expiry info of the token
    function getTokenExpiryInfo(address token) internal returns (int responseCode, IHederaTokenService.Expiry memory expiryInfo){
        (bool success, bytes memory result) = precompileAddress.call(
            abi.encodeWithSelector(IHederaTokenService.getTokenExpiryInfo.selector, token));
        IHederaTokenService.Expiry memory defaultExpiryInfo;
        (responseCode, expiryInfo) = success ? abi.decode(result, (int32, IHederaTokenService.Expiry)) : (HederaResponseCodes.UNKNOWN, defaultExpiryInfo);
    }

    /// Operation to update token expiry info
    /// @param token The token address
    /// @return responseCode The response code for the status of the request. SUCCESS is 22.
    function updateTokenExpiryInfo(address token, IHederaTokenService.Expiry memory expiryInfo) internal returns (int responseCode){
        (bool success, bytes memory result) = precompileAddress.call(
            abi.encodeWithSelector(IHederaTokenService.updateTokenExpiryInfo.selector, token, expiryInfo));
        (responseCode) = success ? abi.decode(result, (int32)) : HederaResponseCodes.UNKNOWN;
    }

    /// Operation to update token info
    /// @param token The token address
    /// @param tokenInfo The hedera token info to update token with
    /// @return responseCode The response code for the status of the request. SUCCESS is 22.
    function updateTokenInfo(address token, IHederaTokenService.HederaToken memory tokenInfo) internal returns (int responseCode) {
        (bool success, bytes memory result) = precompileAddress.call(
            abi.encodeWithSelector(IHederaTokenService.updateTokenInfo.selector, token, tokenInfo));
        (responseCode) = success ? abi.decode(result, (int32)) : HederaResponseCodes.UNKNOWN;
    }

    /// Redirect for token
    /// @param token The token address
    /// @param encodedFunctionSelector The function selector from the ERC20 interface + the bytes input for the function called
    /// @return responseCode The response code for the status of the request. SUCCESS is 22.
    /// @return response The result of the call that had been encoded and sent for execution.
    function redirectForToken(address token, bytes memory encodedFunctionSelector) external returns (int responseCode, bytes memory response) {
        (bool success, bytes memory result) = precompileAddress.call(
            abi.encodeWithSelector(IHederaTokenService.redirectForToken.selector, token, encodedFunctionSelector)
        );

        emit CallResponseEvent(success, result);
        (responseCode, response) = success ? (HederaResponseCodes.SUCCESS, result) : (HederaResponseCodes.UNKNOWN, bytes(""));
    }
}

Example

pageDeploy a Contract Using the Hedera Token Service

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Additional References

• HIP-206