solidity/test/compilationTests/gnosis/Oracles/CentralizedOracle.sol
2019-10-30 17:31:33 +01:00

93 lines
2.0 KiB
Solidity

pragma solidity >=0.0;
import "../Oracles/Oracle.sol";
/// @title Centralized oracle contract - Allows the contract owner to set an outcome
/// @author Stefan George - <stefan@gnosis.pm>
contract CentralizedOracle is Oracle {
/*
* Events
*/
event OwnerReplacement(address indexed newOwner);
event OutcomeAssignment(int outcome);
/*
* Storage
*/
address public owner;
bytes public ipfsHash;
bool public isSet;
int public outcome;
/*
* Modifiers
*/
modifier isOwner () {
// Only owner is allowed to proceed
require(msg.sender == owner);
_;
}
/*
* Public functions
*/
/// @dev Constructor sets owner address and IPFS hash
/// @param _ipfsHash Hash identifying off chain event description
constructor(address _owner, bytes memory _ipfsHash)
public
{
// Description hash cannot be null
require(_ipfsHash.length == 46);
owner = _owner;
ipfsHash = _ipfsHash;
}
/// @dev Replaces owner
/// @param newOwner New owner
function replaceOwner(address newOwner)
public
isOwner
{
// Result is not set yet
require(!isSet);
owner = newOwner;
emit OwnerReplacement(newOwner);
}
/// @dev Sets event outcome
/// @param _outcome Event outcome
function setOutcome(int _outcome)
public
isOwner
{
// Result is not set yet
require(!isSet);
isSet = true;
outcome = _outcome;
emit OutcomeAssignment(_outcome);
}
/// @dev Returns if winning outcome is set
/// @return Is outcome set?
function isOutcomeSet()
public
override
view
returns (bool)
{
return isSet;
}
/// @dev Returns outcome
/// @return Outcome
function getOutcome()
public
override
view
returns (int)
{
return outcome;
}
}