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OracleBroker.sol

pragma solidity >0.4.99 <0.6.0;

// import paymentProcessor interface
// import oracleTypeRegistry interface
// import oracleRegistry interface
// import requestRegistry interface

contract OracleBrokerFront {


    [...]

    function makeRequest(
        bytes32 _oracleType,
        bytes32 _internalId, // An Id for request generated by Product, so the response could be matched to it
        // request data ( inputs interpolated into string, according to format defined in OracleType )
        // callback instructions ( callback contract address, callback method name )
        bytes32[] tagsToPrioritize, // Prioritize Oracles that have these tags ???
    ) public {
        address memory responsibleOracleAddress;

        bytes32 memory requestId;
        OracleType memory oracleType = oracleTypeRegistry.getOracleType(_oracleType);

        responsibleOracleAddress = oracleRegistry.nextResponsibleOracle(
            _oracleType
        )

        requestId = requestRegistry.makeRequest(
            // request data,
            responsibleOracleAddress
        );

        paymentProcessor.storeRequestPayment(
            msg.sender,
            requestId,        //
            oracleType.requestPrice  // TODO: fuzzy: define pricing in Types Registry, or have an additional ledger ?
        )

        emit NewRequest(
            // request specifics
        );

        /*
        Optional - ping responsible oracle to speed the resolution up
        Oracle.at(responsibleOracleAddress).forwardRequest(requestId);
        */
    }


}

contract OracleTypeRegistry {

    enum TypeState { Proposed, Active, Deprecated }

    address owner; // TODO: control privileges

    struct OracleType {
        bytes32 callbackSignature,      // ex. '(uint8,uint256, boolean)'
        bytes32 inputFormat,            // ex.
        bytes32 description,
        unit16 responsePreparationPeriod,
        uint16 responseDeadlinePeriod,
        TypeState state,
    };
    mapping (bytes32 => OracleType) public types;

    constructor(
        //
    ) public {
        // TODO
    }

    // TODO
    function proposeOracleType(
        // oracle type data
    ) public {
        // save oracle type as Proposed
    }

    /* Optional method: update while the Type is still in Proposed state
    function updateOracleType(

    ) public {

    }
    */

    // TODO
    function activateOracleType(
        // oracle type id
    ) public onlyOwner {  // TODO: control privileges
        // transition oracle state to Active
    }

    // TODO
    function deprecateOracleType(
        // oracle type id
    ) public onlyOwner {  // TODO: control privileges
        // transition oracle state to Deprecated
    }

    function getOracleType(
        string _oracleTypeId,
    ) public returns(
        // TODO list public oracle type data
    ) {
        // return oracle type data
    }

    modifier onlyOwner() {
        // authorization
        _;
    }
}

contract OracleRequestRegistry is OracleBrokerBackend {
 
    [...]
 
    function makeRequest(
        address responsibleOracleAddress, 
        // ...
    ) public onlyBrokerFront returns(bytes32) {
        // store request to registry
        // return id
    }

}



contract OraclizeBridge() is oraclize {

    function makeRequest (...) returns (bytes32 queryId) {
        queryId = oraclize.query(...)
    }
    
    function __callback(...) {
        
    }
    
}

transaction.sol

contract transactionDriven {
    
    enum state {initial, state1, state2, state3}
    
    
    state myState;
    address participant1;
    address participant2;
    address participant3;
    
    function first() public {
        require(myState == state.initial);
        myState = state.state1;
        participant1 = msg.sender;
    }
    
    function second() public {
        require(myState == state.state1);
        require(msg.sender != participant1);
        myState = state.state2;
        participant2 = msg.sender;
        
    }
    
    function third() public {
        require(myState == state.state2);
        require(msg.sender != participant1);
        require(msg.sender != participant2);
        myState = state.state3;
        participant3 = msg.sender;
        performAction();
        
    }
    
    function performAction() public {
        // do something
    }
}


contract messageDriven {
    
    address participant1;
    address participant2;
    address participant3;
    
    
    function performAction(uint8[] memory sigV, bytes32[] memory sigR, bytes32[] memory sigS, string memory data) public {
        
        participant1 = ecrecover(keccak256(abi.encodePacked(data)), sigV[1], sigR[1], sigS[1]);
        participant1 = ecrecover(keccak256(abi.encodePacked(data)), sigV[2], sigR[2], sigS[2]);
        participant1 = ecrecover(keccak256(abi.encodePacked(data)), sigV[3], sigR[3], sigS[3]);

        
        // do something
        
        
    }
}