The msgOracle smart-contracts are intended to be the on-chain component (messageToHoneyContract) of SWIP 21.

The MsgOracle is a smart-contract which inherits functionalities from openzeppelin-solidity/ownable. As such, it can define an owner and limit access to certain function to be only performed by the owner. By reading the events emitted by this smart-contract (in particular: LogNewTTL, LogSetMsgPrice and LogRevertMsgPrice), nodes know the latest value of all message prices in Swarm and be guaranteed that their peers apply the same prices.

The msgOracle exposes the following functions:

• Getter function, which returns the Time To Live (TTL) for the contract. TTL signals to the nodes how long a response from the oracle is guaranteed valid; if a node uses an oracle response which is older than TTL seconds, it is not guaranteed to be correct anymore.

• Getter function, which return the current owner of the contract.

• Sets a new Time To Live (TTL). TTL can only be updated after TTL seconds after it was set.
• Stores the previous value of TTL .
• Stores when the function was called.
• Emits a LogNewTTL(uint256 TTL) event on which nodes can listen to be informed on changes in TTL.
• only callable by owner

• informs the node about a new price for a particular swarmMsg, in effect from a certain date (validFrom)
• requires validFrom to be at least TTL seconds in the future. If TTL has been recently updated (not longer than the old value of TTL seconds ago), we use the old value of TTL.
• Emits a LogSetMsgPrice(bytes32 indexed swarmMsg, uint256 price, uint256 validFrom) event.
• only callable by owner

• informs the node to ignore a previous emitted LogSetMsgPrice event with the same arguments as the LogRevertMsgPrice(bytes32 indexed swarmMsg, uint256 price, uint256 validFrom) event, emitted by this function.
• only callable by owner

• Set's the ownership of this smart-contract to the 0 address, which will render all functionalities of this smart-contract forever useless.
• emits an OwnershipTransferred(address indexed previousOwner, address indexed newOwner) event.
• only callable by owner

• Set's the ownership of this smart-contract to another address. Meant for updating the governance around the oracle.
• emits an OwnershipTransferred(address indexed previousOwner, address indexed newOwner) event.
• only callable by owner