EVM

Programming API reference for the Stork EVM contract.

SDK

EVM contracts can program against the Stork contract's interface by using the stork-evm-sdk npm package available on npmjs.com. This SDK provides an interface and useful struct for interacting with the Stork Contract. The Stork contract can also be used via the Pyth and Chainlink adapters. The Stork contract is built using Hardhat.

Getting Started

Solidity

After setting up your Hardhat project, add the stork-evm-sdk to your project dependencies by adding the following line to the "dependencies" section of the programs package.json

// package.json
"dependencies": {
    "@storknetwork/stork-evm-sdk": "^1.0.0"
  }

or with the following command:

npm i @storknetwork/stork-evm-sdk

You can now import the sdk's interface and types with:

// YourContract.sol
import "@storknetwork/stork-evm-sdk/IStork.sol";
import "@storknetwork/stork-evm-sdk/StorkStructs.sol";

Concepts

Upgradeability

The Stork contract is designed to be upgradeable using OpenZeppelin's proxy pattern. Ensure the proxy address remains consistent when interacting with the contract to avoid version mismatches.

Methods

Update Temporal Numeric Values V1

function updateTemporalNumericValuesV1(
    StorkStructs.TemporalNumericValueInput[] calldata updateData
) public payable;

Description

Updates multiple temporal numeric values by verifying signatures and ensuring freshness.

Parameters

• updateData: Array of TemporalNumericValueInput structs containing feed updates.

Behavior

• Verifies the signature of each feed update using the stored EVM public key.

• Updates the feed value if the signature is valid and the value is fresher than the current state.

• Requires sufficient fee based on the number of updates.

Errors

• InvalidSignature (0x8baa579f): If any feed update fails signature verification.

• NoFreshUpdate (0xde2c57fa): If none of the provided updates are fresher than current values.

• InsufficientFee (0x025dbdd4): If the provided fee is less than the required amount.

Get Temporal Numeric Value V1

function getTemporalNumericValueV1(
    bytes32 id
) public view returns (StorkStructs.TemporalNumericValue memory value);

Description

Retrieves the latest temporal numeric value for the specified feed ID. Checks for the staleness threshold set in the state, which varies between chains but is typically 3600 seconds.

Parameters

• id: The identifier of the feed.

Returns

• value: The latest TemporalNumericValue struct for the feed.

Errors

• NotFound (0xc5723b51): If no value exists for the given feed ID.

• StaleValue (0x24c4fe43): If the value is older than the valid time period.

Get Temporal Numeric Value Unsafe V1

function getTemporalNumericValueUnsafeV1(
    bytes32 id
) public view returns (StorkStructs.TemporalNumericValue memory value);

Description

Retrieves the latest temporal numeric value for the specified feed ID without checking its freshness.

Parameters

• id: The identifier of the feed.

Returns

• value: The latest TemporalNumericValue struct for the feed.

Errors

• NotFound (0xc5723b51): If no value exists for the given feed ID.

Get Update Fee V1

function getUpdateFeeV1(
    StorkStructs.TemporalNumericValueInput[] calldata updateData
) public view returns (uint feeAmount);

Description

Calculates the total fee required for the given updates.

Parameters

• updateData: Array of TemporalNumericValueInput structs representing updates.

Returns

• feeAmount: The total fee required for the updates.

Verify Publisher Signatures V1

function verifyPublisherSignaturesV1(
    StorkStructs.PublisherSignature[] calldata signatures,
    bytes32 merkleRoot
) public pure returns (bool);

Description

Verifies multiple publisher signatures against the provided Merkle root.

Parameters

• signatures: Array of PublisherSignature structs.

• merkleRoot: The Merkle root to validate against.

Returns

• bool: True if all signatures are valid and match the Merkle root.

Version

function version() public pure returns (string memory);

Description

Retrieves the current version of the contract.

Returns

• string: The version string (e.g., "1.0.3").

Examples

An example contract can be found in the the stork-external github repo.