Calldata construction
Build an update calldata
This section outlines the calldata format requirements for valid updates. The complete calldata can be constructed by concatenating all bytes in the specified order below.
| Field | Size | Recommended value |
|---|---|---|
| Major version | uint8 | 1 |
| Minor version | uint8 | 0 |
| Trailing Header Size | uint8 | 0 |
| Hyperlane message length | uint16 | length |
Then, comes the hyperlane message:
| Field | Size | Recommended value |
|---|---|---|
| Hyperlane version | uint8 | 1 |
| Signatures | Signatures | - |
| Nonce | uint32 | - |
| Emitter chain id | uint32 | chain id |
| Emitter address | bytes32(starknet address) | - |
| Payload | Payload | - |
Signatures are packed encoded, starting with a single byte indicating the total number of signatures(uint8). Each signature then consists of:
- one-byte index (mapping the signature to its corresponding validator in the Hyperlane contract)
- 32-byte r-component
- 32-byte s-component
- one-byte v-component
Finally the payload:
| Field | Size | Recommended value |
|---|---|---|
| Merkle tree hook address | bytes32 | - |
| Checkpoint root | bytes32 | - |
| Checkpoint index | uint32 | - |
| Message id | uint256 | - |
| Num updates | uint8 | - |
| Update Size | uint16 | length |
| Proof length | uint16 | length |
| Proof | - | - |
| Update data | UpdateData | - |
| Feed id | bytes32 | - |
| Publish time | uint64 | - |
UpdateData represents the packed encoding abi.encodePacked of the desired feed type, which could be SpotMedian, TWAP, Options, Perpetuals, or other supported types.
For applications, the process of building calldata is simplified; it can be retrieving through the get_calldata theoros endpoint.