Oracles
I am currently using Chainlink. How difficult is it to change to Chronicle?β
If you are using Chainlink, you would only have to change the address of your oracle to the Chronicle equivalent. This is because Scribe is partially Chainlink compatible, implementing the most widely, and not deprecated, used functions of the IChainlinkAggregatorV3 interface such as latestRoundData(), decimals(), and latestAnswer().
One thing to keep an eye on is the number of decimals. Chronicle always uses 18 decimals, whereas Chainlink uses different decimals for different oracles. However, if implemented correctly, one can check the decimals and scale them up or down accordingly. Please conduct integration tests and feel free to reach out if there are any issues.
How do I check if an Oracle becomes inactive/ gets deprecated?β
In the event that an Oracle gets deprecated, we will notify all whitelisted customers before offboarding it.
From a technical point of view, if an oracle becomes inactive, the price is set to 0, and the validators (also known as feeds), are removed from the contract. Therefore, the read() function will revert with 0, the tryRead() function will return (false, 0), and the latestRoundData() will return 0 as well.
What do I need to do to read from a Chronicle Oracle?β
Chronicle Oracles are read-protected by a whitelist. To read from an Oracle, the calling address must be tolled (whitelisted).
On testnet networks, the whitelisting mechanism is permissionless, anyone can whitelist an address using the SelfKisser.
On mainnet, the whitelisting mechanism is permissioned. To request access, open a ticket on Discord in the πο½support channel.
What happens if I try to read from an address that is not whitelisted?β
If you try to read from and address that is not tolled (whitelisted), the transaction reverts.
How can I check the validators of an Oracle?β
You can use cast, a CLI tool designed by the Foundry team to streamline the interaction with the EVM.
$ cast call $contract 'feeds()(address[])' --rpc-url $rpc
Returns an array with the validators.
Alternatively, if you prefer to check on Etherscan, navigate to the Read Contract section of the Oracle you want to check, and run the feeds() function. The result will list all the validator addresses that are authorized to sign a price update.
How can I check if an address is whitelisted to read data?β
$ cast call $oracle "tolled(address)(bool)" <your address> --rpc-url $rpc
Returns either true or false.
How can I check how many validators have signed a price message?β
On Etherscan, navigate to the Read Contract section of the Oracle you want to check, and run the bar() function. This returns the number of signatures required for an Oracle update.
What is the update threshold for the Oracles?β
A new aggregation round is triggered after a specified amount of time since the latest update, or if the new offchain value deviates more than a pre-defined threshold for the onchain value, whichever of these conditions occurs first. If the data values stay within the Deviation Threshold, an update will only be triggered every X minutes / hours.
Can the update threshold parameters be modified?β
Yes, the update parameters, including the update and deviation thresholds, can be modified. For the most up-to-date parameters, please check the specific Oracle on the Dashboard. If you'd like to request different parameters, please get in touch.