Oracles
I am currently using Chainlink. How difficult is it to change to Chronicle?​
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?​
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.
How can I check the validators of an Oracle?​
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?​
$ 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?​
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.
Can you provide a comparison of gas usage for a Chronicle Oracle update versus competitors that use a PUSH-based model?​
| Oracle Network | Chain | Pair | Gas | No. validators | Etherscan link |
|---|---|---|---|---|---|
| Chronicle | ETH Mainnet | ETH/USD | 54,620 | 13 | https://etherscan.io/tx/0xf365e0c8def94e3aa666dd443ad10c7b86d9bf55b74878e42cf42e9f5b56fdf3 |
| Chainlink | ETH Mainnet | ETH/USD | 333,602 | 11 | https://etherscan.io/tx/0xe236f406773bd2049549131646cda58497a1a9cb9c03fd624a5552fdd1503bd3 |
| Chronicle | Arbitrum | ETH/USD | 143,266 | 13 | https://arbiscan.io/tx/0xf9e83b4515303b22bbae8274f5b4e3c7b64c988c3b026d40b0984075913609d9 |
| Chainlink | Arbitrum | ETH/USD | 185,113 | 4 | https://arbiscan.io/tx/0xfd7a955985634bba3e26a5820aa277479be096b0695872eee0ccf1b7728b3774 |