info_tfgrid/collections/projectinca/specs_blockchain/oracle_contract.md

Oracle Contracts

An oracle can get information from the world as well as from other blockchains e.g. price of a token

• name e.g. TFT_PRICE
• description
• address, the address of this oracle contract
• link (link to more info about the oracle)
• multisig_accounts e.g. 9 accounts need to sign
• multisig_min_signature e.g. 6 need to sign, this is for releasing the generated token INCA
• smart_contract_addr: address of the smart contract
• period_measure: period in seconds we will measure
• period_calc: period in seconds over which we will calculate min, max and avg (is rolling window)

default methods

• get(name:string) -> fl64
  • will return minimum, maximum, average over the specified period _calc

Example record in Blockchain DB

{
  "oracle_contract": {
    "name": "TFT_PRICE",
    "description": "Oracle contract for retrieving TFT token price",
    "address": "0xFEDCBA9876543210FEDCBA9876543210FEDCBA98",
    "link": "https://example.com/tft_price_oracle_info",
    "multisig_accounts": [
      "0x1111111111111111111111111111111111111111",
      "0x2222222222222222222222222222222222222222",
      "0x3333333333333333333333333333333333333333",
      "0x4444444444444444444444444444444444444444",
      "0x5555555555555555555555555555555555555555",
      "0x6666666666666666666666666666666666666666",
      "0x7777777777777777777777777777777777777777",
      "0x8888888888888888888888888888888888888888",
      "0x9999999999999999999999999999999999999999"
    ],
    "multisig_min_signature": 6,
    "smart_contract_addr": "0xABCDEF1234567890ABCDEF1234567890ABCDEF12",
    "period_measure": 3600,
    "period_calc": 86400
  }
}

Implementation

sequenceDiagram
    participant ExternalSource
    participant OracleContract
    participant MultisigAccounts
    participant SmartContract
    participant BlockchainDB
    participant Requester

    loop Every period_measure (3600 seconds)
        ExternalSource->>OracleContract: Provide TFT price data
        OracleContract->>SmartContract: Validate and process data
        
        alt Data is valid
            SmartContract->>MultisigAccounts: Request signatures
            
            loop Until multisig_min_signature reached
                MultisigAccounts->>MultisigAccounts: Collect signatures
            end
            
            MultisigAccounts-->>SmartContract: Return collected signatures
            
            alt Sufficient signatures collected
                SmartContract->>BlockchainDB: Store price data
                BlockchainDB-->>SmartContract: Confirm storage
            else Insufficient signatures
                SmartContract->>OracleContract: Discard data (insufficient signatures)
            end
        else Data is invalid
            SmartContract->>OracleContract: Reject invalid data
        end
    end

    Requester->>OracleContract: Call get("TFT_PRICE")
    OracleContract->>SmartContract: Process request
    SmartContract->>BlockchainDB: Retrieve price data for period_calc (86400 seconds)
    BlockchainDB-->>SmartContract: Return price data
    SmartContract->>SmartContract: Calculate min, max, avg
    SmartContract-->>OracleContract: Return calculated values
    OracleContract-->>Requester: Provide min, max, avg price