doc

Integration of TCRs, CPM and Ocean Tokens with Solidity

name: Integration of TCRs, CPM, and Ocean tokens with Solidity
type: development
status: initial draft
editor: Fang Gong <fang@oceanprotocol.com>
collaborator: Aitor Argomaniz <aitor@oceanprotocol.com>
date: 08/06/2018

Further Documentation

• TCR Owner's Manual

Objective

In this project, we put following modules together:

• TCRs: users create challenges and resolve them through voting to maintain registries;
• Ocean Tokens: the intrinsic tokens circulated inside Ocean network, which is used in the voting of TCRs;
• Curated Proofs Market: the core marketplace where people can transact with each other and curate assets through staking with Ocean tokens.

Public Interface

The project exposes the following public interfaces:

Token Curated Registry (OceanRegistry.sol)

//Allows a user to start an application. Takes tokens from user and sets apply stage end time.
function apply(bytes32 _listingHash, uint _amount, string _data);

// Allows the owner of a listingHash to increase their unstaked deposit.
function deposit(bytes32 _listingHash, uint _amount);

//Allows the owner of a listingHash to decrease their unstaked deposit.
function withdraw(bytes32 _listingHash, uint _amount);

// Allows the owner of a listingHash to remove the listingHash from the whitelist
function exit(bytes32 _listingHash);

// Starts a poll for a listingHash which is either in the apply stage or already in the whitelist.
function challenge(bytes32 _listingHash, string _data);

// Updates a listingHash’s status from ‘application’ to ‘listing’ or resolves a challenge if one exists.
function updateStatus(bytes32 _listingHash);

// Called by a voter to claim their reward for each completed vote.
function claimReward(uint _challengeID, uint _salt);

// Calculates the provided voter’s token reward for the given poll.
function voterReward(address _voter, uint _challengeID, uint _salt);

// Determines whether the given listingHash be whitelisted.
function canBeWhitelisted(bytes32 _listingHash);

// Returns true if the provided listingHash is whitelisted
function isWhitelisted(bytes32 _listingHash);

// Determines the number of tokens awarded to the winning party in a challenge.
   function determineReward(uint _challengeID);

Marketplace (OceanMarket.sol)

// Register data assets
function register(bytes32 assetId, uint256 price) public returns (bool success);

// consumer can make payment
function sendPayment(bytes32 _paymentId, address _receiver, uint256 _amount, uint256 _expire) public returns (bool);

// release fund to provider - must be called by OceanAuth contract
function releasePayment(bytes32 _paymentId) public isLocked(_paymentId) returns (bool);

// refund payment - must be called by OceanAuth contract
function refundPayment(bytes32 _paymentId) public isLocked(_paymentId) returns (bool);

// verify the payment is received
function verifyPaymentReceived(bytes32 _paymentId) public view returns (bool);

// Generate Unique Id for asset using input string parameter
function generateStr2Id(string contents) public pure returns (bytes32);

// Generate Unique Id for asset using input bytes parameter
function generateBytes2Id(bytes contents) public pure returns (bytes32);

// Market checks the TCR voting results
function checkListingStatus(bytes32 listing) public view returns(bool);

// Market changes the status of TCR according to voting result
function changeListingStatus(bytes32 listing, bytes32 assetId) public returns(bool);

On-Chain Authorization (OceanAuth.sol)

// consumer request access to resource
function initiateAccessRequest(bytes32 resourceId, address provider, string pubKey, uint256 timeout) public returns (bool);

// provider commit the access request
function commitAccessRequest(bytes32 id, bool isAvailable, uint256 expirationDate, string discovery, string permissions, string accessAgreementRef, string accessAgreementType) public onlyProvider(id) isAccessRequested(id) returns (bool);

// consumer can cancel the access request
function cancelAccessRequest(bytes32 id) public isAccessCommitted(id) onlyConsumer(id);

// provider deliver the access token
function deliverAccessToken(bytes32 id, bytes encryptedAccessToken) public onlyProvider(id) isAccessCommitted(id) returns (bool);

// provider verify the delivery of JWT access token
function verifyAccessTokenDelivery(bytes32 id, address _addr, bytes32 msgHash, uint8 v, bytes32 r, bytes32 s) public
onlyProvider(id) isAccessComitted(id) returns (bool);

Query functions

// provider query the temp public key
function getTempPubKey(bytes32 id) public view onlyProvider(id) isAccessCommitted(id) returns (string);

// consumer query the encrypted access token
function getEncryptedAccessToken(bytes32 id) public view onlyConsumer(id) isAccessCommitted(id) returns (bytes);

// provider uses this function to verify the signature comes from the consumer
function isSigned(address _addr, bytes32 msgHash, uint8 v, bytes32 r, bytes32 s) public pure returns (bool);

// verify the status of access request
function verifyCommitted(bytes32 id, uint256 status) public view returns (bool);

// Return true or false if an Asset is active given the assetId
function checkAsset(bytes32 assetId) public view returns (bool);

// Retrieve the price of asset
function getAssetPrice(bytes32 assetId) public view returns (uint256);

Events

// OceanMarket Events
event AssetRegistered(bytes32 indexed _assetId, address indexed _owner);
event PaymentReceived(bytes32 indexed _paymentId, address indexed _receiver, uint256 _amount, uint256 _expire);
event PaymentReleased(bytes32 indexed _paymentId, address indexed _receiver);
event PaymentRefunded(bytes32 indexed _paymentId, address indexed _sender);

// OceanAuth Events
event AccessConsentRequested(bytes32 _id, address _consumer, address _provider, bytes32 _resourceId, uint _timeout, string _pubKey);
event AccessRequestCommitted(bytes32 _id, uint256 _expirationDate, string _discovery, string _permissions, string _accessAgreementRef);
event AccessRequestRejected(address _consumer, address _provider, bytes32 _id);
event AccessRequestRevoked(address _consumer, address _provider, bytes32 _id);
event EncryptedTokenPublished(bytes32 _id, bytes _encryptedAccessToken);
event AccessRequestDelivered(address _consumer, address _provider, bytes32 _id);

File Structure

There are several folders and each includes solidity source files for each module:

• auth: OceanAuth contract for authorization;
• plcrvoting: Partial Lock Commit Reveal Voting System;
• tcr: the TCRs related files;
• token: Ocean tokens based on ERC20 standard;
• zeppelin: the library files from OpenZeppelin;
• Oceanmarket.sol: curated proofs market (on-going work);
• Migrations.sol: default contract for migration.

Architecture of Solidity Market Contract

• First draft of UML class diagram