Oracle

[Source]

(Added by the PriceOracle amendment.)

An Oracle ledger object represents a Price Oracle created by an account on the Xahau ledger. It stores one or more asset price data points and is identified by the owner account together with a document ID. Oracle objects are created and updated via OracleSet transactions and deleted via OracleDelete transactions.

Example JSON

{
    "LedgerEntryType": "Oracle",
    "Owner": "rHb9CJAWyB4rj91VRWn96DkukG4bwdtyTh",
    "OracleDocumentID": 1,
    "Provider": "70726F7669646572",
    "AssetClass": "63757272656E6379",
    "LastUpdateTime": 816348759,
    "PriceDataSeries": [
        {
            "PriceData": {
                "BaseAsset": "XAH",
                "QuoteAsset": "USD",
                "AssetPrice": 74560,
                "Scale": 4
            }
        },
        {
            "PriceData": {
                "BaseAsset": "BTC",
                "QuoteAsset": "USD",
                "AssetPrice": 6800000,
                "Scale": 2
            }
        }
    ],
    "URI": "697066733A2F2F",
    "OwnerNode": "0000000000000000",
    "PreviousTxnID": "5463C6E08862A1FAE5EDAC12D70ADB16546A1F674930521295BC082494B62924",
    "PreviousTxnLgrSeq": 6,
    "index": "49647F0D748DC3FE26BDACBC57F251AADEFFF391403EC9BF87C97F67E9977FB0"
}

Fields

An Oracle object has the following fields:

Field	JSON Type	Internal Type	Required?	Description
Owner	String	AccountID	Yes	The account that created and owns this Oracle. Only this account can update or delete it.
OracleDocumentID	Number	UInt32	Yes	The unique identifier for this Oracle within the owner account.
Provider	String	Blob	Yes	Hex-encoded identifier of the data provider (e.g. the oracle service name). Max 256 bytes.
AssetClass	String	Blob	Yes	Hex-encoded string describing the category of assets (e.g. 63757272656E6379 = “currency”). Max 16 bytes.
LastUpdateTime	Number	UInt32	Yes	Ripple Epoch timestamp (seconds since January 1, 2000) of the last price update.
PriceDataSeries	Array	Array	Yes	Array of PriceData objects (1–10 entries). Entries are stored in canonical sorted order by BaseAsset/QuoteAsset pair.
URI	String	Blob	No	Hex-encoded URI pointing to supplementary off-chain data (e.g. an IPFS CID). Max 256 bytes.
OwnerNode	String	UInt64	Yes	A hint indicating which page of the owner’s directory links to this object.
PreviousTxnID	String	Hash256	Yes	The identifying hash of the transaction that most recently modified this object.
PreviousTxnLgrSeq	Number	UInt32	Yes	The ledger index of the ledger that contains the transaction that most recently modified this object.
LedgerEntryType	String	UInt16	Yes	The value 0x0080, mapped to the string Oracle, indicates this is an Oracle object.

PriceData Object

Each entry in PriceDataSeries contains a PriceData object:

Field	JSON Type	Internal Type	Required?	Description
BaseAsset	String	Currency	Yes	The asset being priced (e.g. "XAH", "BTC").
QuoteAsset	String	Currency	Yes	The denomination currency (e.g. "USD", "EUR").
AssetPrice	Number	UInt64	No	The price as a scaled integer. The effective price is AssetPrice × 10^(-Scale).
Scale	Number	UInt8	No	Decimal exponent (0–10) used to derive the effective price. Example: AssetPrice = 74560, Scale = 4 → effective price = 7.456.

Reserve

An Oracle object consumes owner reserves based on the number of PriceData pairs stored:

Pairs	Owner reserves consumed
1–5	1
6–10	2

Oracle ID Format

The ID of an Oracle object is the SHA-512Half of the following values, concatenated in order:

• The Oracle space key (0x0152)
• The AccountID of the Owner
• The OracleDocumentID as a 32-bit unsigned integer