BTCBalance
The BTCBalance
query type allows users to query a BTC balance by address and timestamp. Users can tip Tellor reporters to bridge balances from Bitcoin to any tellor enabled chain.
A query's parameters may change for each instance of your query type.
The BTCBalance
query type's parameters are defined as:
1. btcAddress
- description: the address of the bitcoin hodler
- value type: `string`
2. timestamp
- description: timestamp which will be rounded down to the closest Bitcoin block
- value type: `uint256`
see here for more information on calldata
Response should return the value to 18 decimals
- abi_type: uint256
- packed: false
Query data is used to form your new Query's unique identifier, or query ID, and it's also included in emitted contract events so Tellor users and reporters can programmatically construct query objects.
To generate the query data for an instance of your new Query type, first UTF-8 encode the parameter values in the order specified above. Then encode those bytes
with the Query's type string.
For example, to get the query data of an example instance of a BTCBalance
query using Solidity:
string btcAddress = "3Cyd2ExaAEoTzmLNyixJxBsJ4X16t1VePc";
bytes queryData = abi.encode("BTCBalance", abi.encode(btcAddress,1705954706));
The Query ID is your new Query's unique identifier. It's important to have one because many kinds of data pass through the Tellor ecosystem.
To generate a query ID, get the bytes32
value of the keccak
hash of the query data (defined above). For example, in Solidity:
bytes32 queryId = keccak256(queryData);
You can use this tool to generate query IDs.
The JSON representation of your new query type is needed to construct query objects in a variety of languages. It contains the essential components of your query: type name, parameters in an ordered list and their corresponding value types, as well as the expected response type for the query.
the JSON representation of a BTCBalance
query:
{
"type": "BTCBalance",
"abi": [
{
"type": "string",
"name": "btcAddress",
},
{
"type": "uint256",
"name": "timestamp",
},
],
"response": {
"type": "uint256",
"packed": false,
}
}
to query a bitcoin address at 22 January 2024 at 3:06pm EST
bytes queryData = abi.encode("BTCBalance", abi.encode("3Cyd2ExaAEoTzmLNyixJxBsJ4X16t1VePc",1705954706));
bytes32 queryId = keccak256(queryData)
the queryData: 0x00000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000080000000000000000000000000000000000000000000000000000000000000000a42544342616c616e63650000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000a000000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000065aecd920000000000000000000000000000000000000000000000000000000000000022334379643245786141456f547a6d4c4e7969784a7842734a34583136743156655063000000000000000000000000000000000000000000000000000000000000
this queryId is 0xee2cbdde34725cfa760bc074083ca85b3f82747d8f9b6baa79cecc2cb107c2a
to format the response (.31 BTC), pull out to 18 decimals:
bytes exampleResponse = abi.encode();
this example response in bytes is...
0x000000000000000000000000000000000000000000000000044d575b885f0000
Note that following this guide does not prevent you from being disputed or guarantee reporters will properly put a value on-chain. Tellor is decentralized. This repo is a start to the education necessary for a fully decentralized oracle, but please focus on communication and working with reporters to prevent unneccesary disputes and at the same time encourage monitoring and punishment of bad data.
Make sure to...
- use timestamps old enough that block won't be reverted or rolled back (you will be disputed)
All the reporters need is a btc node or trusted explorer!