Carrot contracts

The smart contracts powering Carrot's efficient incentivization. Both the contracts and the tests are written in Solidity using Foundry.

Contributing

Want to contribute? Check out the CONTRIBUTING.md file for more info.

KPI token and oracle templates and managers

Carrot is designed with flexibility in mind. The maximum amount of flexibility is achieved by allowing to create KPI token and oracle templates "on the go" (potentially by thrid parties too). Templates are self contained apps running on the Carrot platform and implementing both a frontend and a backend (the backend generally consists of one or more smart contracts).

Anyone can potentially code the functionality they want/need in Carrot and use it freely, putting almost no limits on creativity for incentivization campaigns.

This is mainly achieved using 2 contracts: KPITokensManager and OraclesManager. These contracts act as a registry for both KPI token and oracle templates, and at the same time can instantiate specific templates (using ERC-1167 clones to maximize gas efficiency).

Each of these managers support template addition, removal, upgrade, update and instantiation, as well as some readonly functions to query templates' state.

Most of these actions are protected and can only be performed by specific entities in the platform. In particular, addition, removal, upgrade and update can only be performed by the manager contract's owner (governance), while template instantiation can only be initiated by the KPITokensFactory.

Carrot comes out of the box with powerful KPI token and oracle templates, with the goal of encouraging the community to come up with additional use cases that can also lead to entirely custom-made products based on Carrot's platform.

KPITokensFactory

The KPI tokens factory is ideally the contract with which KPI token creators will interact the most, and the glue of the overall architecture. Its most important function is createToken, which takes in 4 parameters, _id, _description, _initializationData and _oraclesInitializationData. The factory is simply in charge of initializing the KPI token campaign overall, and collecting an arbitrary protocol fee in the process.

Explanation of the input parameters follows:

• _id: an uint256 telling the factory which KPI token template must be used.
• _description: a string describing what the KPI token is about (the goals, how they can be reached, and eventually info about how to answer any attached oracles, if the oracles are crowdsourced). In order to save on gas fees, it is highly advisable and the standard procedure to upload a file to IPFS and pass a CID here. An official JSON schema specification for how the description has to look like is a current work in progress, the idea being that if the description of a KPI token does not conform to the JSON schema, it won't be shown in the official frontend operated by Carrot Labs.
• _initializationData: ABI-encoded KPI token initialization data specific to the template that the user wants to use. To know what data to use and how to encode it as a developer, have a look at the code for the template you want to use, in particular to the initialize function. For users, this process is completely abstracted as the Carrot frontend (through the template's frontend in the campaign creation UI) will take care of collecting the necessary data.
• _oraclesInitializationData: ABI-encoded oracles data specific to the instantiated template. This data is used by the KPI token template to instantiate any oracles needed to report goals' data back on-chain. To know what data to use and how to encode it, have a look at the code for the template you want to use, in particular at the initializeOracles function. Again, this process is handled autonomously by the template's frontend for end users.

Warning The sections below are for information only. Third party template development is not fully supported yet and we're still defining the process and tooling required in order to make it a possibility.

Implementing a KPI token template

A KPI token template can be defined by simply implementing the IKPIToken interface. The functions that must be overridden are:

• initialize: this function is called by the factory while initializing the KPI token and contains all the initialization logic (collateral transfers, state setup, KPI token minting and transfer to any eligible party etc). 10 input parameters are passed in by the factory in a struct:
  • creator: the address of the account creating the KPI token.
  • oraclesManager: the address of the oracles manager contract, which can be used to instantiate oracles.
  • kpiTokensManager: the address of the KPI tokens manager contract.
  • feeReceiver: the address of the contract to be sent any fees collected by the protocol.
  • kpiTokenTemplateId: the identifier of the KPI token template being used.
  • kpiTokenTemplateVersion: the version of the KPI token template being used.
  • kpiTokenTemplateVersion: the version of the KPI token template being used.
  • description: the description of the campaign. Officially, it should be an IPFS CID pointing to the specification of the campaign.
  • expiration: a UNIX epoch timestamp at which the KPI token will expire. The expiration logic should make the KPI token expire worthless when this timestamp is reached. This is used to defend against a maliciously unresponsive oracle that might cause funds to get stuck in the KPI token.
  • kpiTokenData: template-specific ABI-encoded data that will the used to initizalize the chosen KPI token template.
  • oraclesData: template-specific ABI-encoded data that will the used to initizalize the chosen oracle template(s).
• finalize: finalization logic is implemented here. This function should only be callable by the oracles associated with the token. Once all the oracles have reported their final results, logic to properly allocate the collaterals (either to the KPI token holders or the KPI token creator, depending on the results) must be implemented accordingly. Any non-redeemable collateral should at this point be sent back to the KPI token creator.
• redeem: this is the function KPI token holders call to redeem the collateral they have earned (if any was unlocked by finalize). This function should ideally (but not necessarily) burn the user-held KPI token(s) in exchange for the collateral.
• owner: a view function returning the address of the KPI token's owner.
• transferOwnership: a function to change the KPI token's ownership.
• template: a view function to fetch the template used to create the KPI token.
• description: a view function to fetch the KPI token campaign's description.
• finalized: a view function that helps understand if the KPI token is in a finalized state or not.
• expiration: a view function that returns the expiration timestamp of the KPI token.
• creationTimestamp: a view function that returns the creation timestamp of the KPI token.
• data: a view function that returns ABI-encoded data about the internal state of the KPI token (what the function returns specifically is up to the template implementation).
• oracles: a view function that returns an address array of the oracles being used by the KPI token.

In general, a good place to have a look at to get started with KPI token development is the ERC20KPIToken implementation.

Implementing an oracle template

An oracle template can be defined by simply implementing the IOracle interface. The functions that must be overridden are:

• initialize: this function is called by a KPI token template while initializing a campaign, and when the point has been reached that the KPI token needs to instantiate its oracles. The input parameters passed by the KPI token are the following:
  • creator: the address of the account creating the KPI token.
  • kpiToken: the address of the KPI token that wants to create the oracle.
  • templateId: the identifier of the oracle template being used.
  • templateVersion: the version of the oracle template being used.
  • data: template-specific ABI-encoded data that will the used to initizalize the oracle.
• kpiToken: view function returning the KPI token address this oracle is attached to.
• template: a view function to fetch the template used to create the oracle.
• finalized: a view function that helps understand if the oracle is in a finalized state or not.
• data: a view function that returns ABI-encoded data about the internal state of the oracle (what the function returns specifically is up to the template implementation).

In general, a good place to have a look at to get started with oracle development is the RealityV3Oracle implementation.