spec

program/SPEC.md

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+The Solana FluxAggregator program is modeled after the [FluxAggregator.sol](https://github.com/smartcontractkit/chainlink/blob/master/evm-contracts/src/v0.6/FluxAggregator.sol) contract in ChainLink.
+
+Data submissions happen rounds. In each round `minSubmissions` must be achieved to arrive at an answer.
+
+- An oracle must wait restartDelay rounds before being allowed to initialize a round
+  - restarDelay should default to `oraclesCount/3`
+- Oracles should submit a new round when value deviates at least minDeviation
+  from the latest answer.
+  - minDeviation should default to 0.1%
+  - This is not enforced by the smart contract
+- `latestAnswer` should return the median, as well as the `latestAnswerResolvedTime` timestamp
+- A round updates the latest answer when minSubmissions is reached, taking the median
+- Each additional answer in the same round below maxSubmissions would recalculate the median, and update the latest answer
+- If rounds stop updating (i.e. not enough oracles to reach `minSubmissions`), the latest answer is always the last round that had resolved
+- An oracle cannot submit to the previous round. The transaction will revert, and the oracle should retry
+
+Wont implement:
+
+- Oracle can start a new round only if the round fails to resolve an answer after `roundTimout` (while satisfying `restartDelay`)
+  - Reason: restartDelay is sufficient
+- An authorized requester can start a new round at any time, limited by `requesterRestartDelay`
+  - Reason: just ask oracle do it
+- Feedback: Oracles can submit to the previous round if the current round has not reached minSubmissions
+  - Reason: This would complicate implementation, and doesn't provide much value, since on solana tx are really cheap. Reverted TXs are no big deal.