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Basic Request Model

Contracts Overview​

'Tenet Oracle Architecture'

TenetOracleClient​

[TenetOrackeClient] is a parent contract that enables smart contracts to consume data from oracles.

The client constructs and makes a request to a known Tenet Oracle oracle through the transferAndCall function, implemented by the TENET token. This request contains encoded information that is required for the cycle to succeed. In the TenetOracleClient contract, this call is initiated with a call to sendTenetOracleRequestTo.

TENET Token​

Tenet Oracle utilises an ERC-677 compliant version of TENET token which implements transferAndCall, a function that allows tokens to be transferred whilst also triggering logic in the receiving contract within a single transaction. The amount of TENET available as rewards for Tenet Oracle utilisation is set through our native gauge voting system by veTENET holders.

Oracle Contract​

[Oracle contracts] are owned by oracle node operators, which run alongside off-chain oracle nodes.

Request​

The client contract that initiates this cycle must create a request with the following items:

  • The oracle address.
  • The job ID, so the oracle knows which tasks to perform.
  • The callback function, which the oracle sends the response to.

Oracle contracts are responsible for handling on-chain requests made through the TENET token, by implementing onTokenTransfer as aTenetTokenReceiver. Upon execution of this function, the oracle contract emits an OracleRequest event containing information about the request. This event is crucial, as it is monitored by the off-chain oracle node which acts upon it.

Fulfillment​

For fulfillment, the oracle contract has a fulfillOracleRequest function which is used by the node to fulfill a request once it has the result of the job. This function returns the result to the TenetOracleClient using the callback function defined in the original request.

Off-Chain Oracle Node​

The off-chain oracle node is responsible for listening for events emitted by its corresponding on-chain smart contract. Once it detects an OracleRequest event, it uses the data emitted to perform a job.

The most common job type for a Node is to make a GET request to an API, retrieve some data from it, parse the response, convert the result into blockchain compatible data, then submit it in a transaction back to the oracle contract, using the fulfillOracleRequest function.