https://github.com/onflow/band-oracle-contracts
Contracts and related for integration with Band protocol Oracle Network
https://github.com/onflow/band-oracle-contracts
blockchain flow oracle
Last synced: 4 months ago
JSON representation
Contracts and related for integration with Band protocol Oracle Network
- Host: GitHub
- URL: https://github.com/onflow/band-oracle-contracts
- Owner: onflow
- License: apache-2.0
- Created: 2023-08-17T14:32:00.000Z (almost 2 years ago)
- Default Branch: main
- Last Pushed: 2025-02-05T19:44:08.000Z (5 months ago)
- Last Synced: 2025-02-05T20:50:05.423Z (5 months ago)
- Topics: blockchain, flow, oracle
- Language: Cadence
- Homepage: https://flow.com/
- Size: 91.8 KB
- Stars: 3
- Watchers: 19
- Forks: 7
- Open Issues: 2
-
Metadata Files:
- Readme: README.md
- Contributing: CONTRIBUTING.md
- License: LICENSE
- Code of conduct: CODE_OF_CONDUCT.md
- Codeowners: .github/CODEOWNERS
- Security: SECURITY.md
Awesome Lists containing this project
README
# Band Oracle Contract
The Cadence smart contract enabling integration of the Band Protocol Oracle network. The oracle network presently offers the full set of [price quotes](https://data.bandprotocol.com/) from the Band Standard Dataset. These are available for any Cadence applications, contracts or transactions to use and presently charges no fees.
Currently supported cryptocurrency token pairs are:
* ETH, FLOW, USDC, USDT, WBTC
* BNB, XRP, ADA, DOGE, POL (MATIC)
* SOL, DOT, LTC, SHIB. TRX
* AVAX, DAI, WBTC, LINK, ATOM
* XLM, AAVE, S (FTM), CRV, OP
* CAKE, DYDX, 1INCH, BAT, SUSHI
* UNI, SUI
Currently supported fiat currency pairs are:
* KRW, INR, PLN, HKD, TWD
* THB, TRY, AUD, BRL, CAD
* CHF, CNY, CZK, EUR, GBP
* JPY, MYR, NZD, PHP, RUB
* SEK, SGD
To learn more about Band Protocol please refer to: https://faq.bandprotocol.com/
## Contract Addresses
|Name|Testnet|Mainnet|
|----|-------|-------|
|[BandOracle](contracts/BandOracle.cdc)|[0x2c71de7af78d1adf](https://contractbrowser.com/A.2c71de7af78d1adf.BandOracle)|[]()|
|[BandOracle](contracts/BandOracle.cdc)|[]()|[0x6801a6222ebf784a](https://contractbrowser.com/A.6801a6222ebf784a.BandOracle)|
## How it works?
The contract keeps a record of symbols and the corresponding financial price data for them. While financial data are only updated by authorized BandChain relayers, they can be queried via a script by any user or application on the Flow blockchain.
### Storing the data
Market for each symbol is stored on a dictionary as a contract level field `access(contract) let symbolsRefData: {String: RefData}`. The `RefData` structs stores the following information:
```cadence
pub struct RefData {
// USD-rate, multiplied by 1e9.
pub var rate: UInt64
// UNIX epoch when data is last resolved.
pub var timestamp: UInt64
// BandChain request identifier for this data.
pub var requestID: UInt64
}
```
This struct provides the caller with the data received from the oracle network for the symbol in question. Keep in mind that all data is normalized and stored using a USD conversion rate, meaning that conversions into other symbols will derive from that.
### Updating the data
The account where the contract is deployed will be granted an `OracleAdmin` resource. This resource can create `DataUpdater` resources and publish a `{&RelayUpdate}` capability to them. An authorized account - belonging to a relayer - can claim said capability at the time of creating a `Relay` resource. This resource will grant the ability to call the `updateData` method that will call contract function `access(contract) fun updateRefData (symbolsRates: {String: UInt64}, resolveTime: UInt64, requestID: UInt64)` which in turn updates the `symbolsRefData` dictionary.
### Querying the data
When invoking the public function `pub fun getReferenceData (baseSymbol: String, quoteSymbol: String): RefData?` calling contracts or scripts would be provided the price corresponding to `quoteSymbol` in the `baseSymbol` currency. If there are no entries registered for either the base or quote symbols the function will return `nil`.
### Fees
[TBD]