Contract expiration and token management ⏳
Services 0.30 completes the HIP-514 roadmap for making Hedera native tokens manageable via smart contracts. There are five new system contracts: getTokenExpiryInfo(address), updateTokenExpiryInfo(address, Expiry), isToken(address token), getTokenType(address token), and updateTokenInfo(address, HederaToken).
The updateTokenInfo(address, HederaToken) call is especially powerful. If a token's admin key signs the transaction calling a contract, that contract can now make itself the token's treasury, assume authority to mint or burn units or NFTs, and so on.
⚠️ Contract authors should know this release initiates Hedera's expiration and rent model for contracts. There will be two visible effects immediately after the 0.30 upgrade:
- All non-deleted contracts will have their expiry extended to at least 90 days after the upgrade date.
- Deleted contracts will start to be purged from state; so a
getContractInfoquery that previously
returnedCONTRACT_DELETEDmay now reportINVALID_CONTRACT_ID.
About 90 days after the 0.30 upgrade, some contracts will begin to expire. The network will try to automatically charge the renewal fee (approximately $0.026 for 90 days) to the expired contract's auto-renew account. If an auto-renew account has zero balance, the network will then try to charge the contract itself.
A contract unable to pay renewal fees will enter a week-long "grace period" during which it is unusable, unless its expiry is extended via ContractUpdate or it receives hbar. After this grace period, the contract will be purged from state.
‼️ We strongly encourage all contract authors to set an auto-renew account for their contract. This isolates the contract logic from the existence of rent.
This release also brings two peripheral improvements:
- It will become possible to schedule a
CryptoApproveAllowancetransaction. - Mirror node operators will be able to use the daily
NodeStakeUpdateexport to track the current values of several key staking properties. Please review the linked protobuf comments for more details on these properties.
Contributors
We'd like to thank all the contributors who worked on this release!
- @alshapi
- @bugbytesinc
- @Daniel-K-Ivanov
- @dimitar-dinev
- @ivanparnarev
- @IvanKavaldzhiev
- @jasperpotts
- @JeffreyDallas
- @joan41868
- @mhess-swl
- @MiroslavGatsanoga
- @Neeharika-Sompalli
- @OlegMazurov
- @qnswirlds
- @rbair23
- @rjuang
- @rusiboyadjiev
- @shemnon
- @SimiHunjan
- @statop
- @stoqnkpL
- @superboo
- @tdermendzhievv
- @tinker-michaelj