CarPass_Solidity

A Solidity smart contract for CarPass decentralization

CarPass-Smart-Contract

A mid-decentralized solution for car mileage approval running on Ethereum

This allows any user to verify the mileage, model, year of Entry Into Circulation, and the owner's Ethereum of any vehicle , whenever and wherever they are , for free.

Only approved mechanics can add a millage check to a vehicle. They are defined here as Oracles.

Only the Smart Contract owner can create new Oracles.

Data model

Two data models (struct) are created: the CarPass itself and the kilometerCheck

the CarPass struct contains everything about the vehicle, from the chassisNumber to the list of all the millieage check the car has passed.

struct CarPass {
    string chassisNumber;
    uint32  yearEntryIntoCirculation;
    uint8  numberOfChecks;
    string carModel;
    string carBrand;
    address ownerAddress;
    mapping(uint8 => KillometerCheck) kilometers;
    
}

The KilometerCheck is the struct defining a particular mileage check, containing the address of the Oracle who performed it, the mileage that has been registered, and the timestamp of when it has been done.

struct KillometerCheck {
    uint date;
    uint32 kilometers;
    address oracleAddress;
}

Methods

1 createNewCarPass

function createNewCarPass(string _chassisNumber, uint32 _yearEntryIntoCirculation, string _carModel, string _carBrand, address _ownerAddress) noCarpassForChassisNumber( _chassisNumber ) public {
    require(_yearEntryIntoCirculation < now);
    carPasses[_chassisNumber] = CarPass(_chassisNumber, _yearEntryIntoCirculation,0, _carModel, _carBrand, _ownerAddress);
}

Lets you create a brand-new CarPass with few parameters: the chassis number of the vehicle, the year of entry, the car model, the car brand and the owner address

2 addKilometerCheck

function addKilometerCheck (string _chassisNumber, uint32 _kilometers ) onlyOracle carPassMustExist(_chassisNumber) valideKilometer(_chassisNumber, _kilometers) public {
    CarPass storage cp = carPasses[_chassisNumber];
    cp.kilometers[cp.numberOfChecks] = KillometerCheck(now, _kilometers, msg.sender);
    cp.numberOfChecks ++;
}

Lets Oracles create new mileage check.

3 createOracle

function createOracle(address newOracle) external onlyOwner {
    isOracle[newOracle] = true;
}

Lets the smart contract owner creates new Oracles

4 seeCarPass

function seeCarPass(string _chassisNumber) carPassMustExist(_chassisNumber) external view returns(string, string,address, uint[]) {
    uint timeChecked = carPasses[_chassisNumber].numberOfChecks;
    uint[] memory checks = new uint[](timeChecked);
    for(uint8 i = 0; i < timeChecked ; i++) {
        checks[i]= carPasses[_chassisNumber].kilometers[i].kilometers;
    }
    return(carPasses[_chassisNumber].carModel, carPasses[_chassisNumber].carBrand,  carPasses[_chassisNumber].ownerAddress, checks);
}

Lets any user see the details of a specic CarPass from the chassis Number

5 seeParticularCheck

function seeParticularCheck (string _chassisNumber, uint8 _checkId) carPassMustExist(_chassisNumber) external view returns(uint, uint32, address) {
   return(carPasses[_chassisNumber].kilometers[_checkId].date, carPasses[_chassisNumber].kilometers[_checkId].kilometers,carPasses[_chassisNumber].kilometers[_checkId].oracleAddress);
}

Lets any user check the specs of a particular kilometer check from specific CarPass

6 changeCarOwner

function changeCarOwner(string _chassisNumber, address _newOwner) onlyCarOwner(_chassisNumber) external {
    require(_newOwner != msg.sender);
    carPasses[_chassisNumber].ownerAddress = _newOwner;
}

Lets car owners transfer ownership to a new person

ValerianThomas/CarPass_Solidity