Snapshot_CheckSnapPassed

Snapshot_CheckSnapPassed is an async mandate that uses Chainlink Functions to verify if a Snapshot proposal has concluded and if a specific choice has won.

Overview

This mandate extends the verification logic of Snapshot_CheckSnapExists. In addition to verifying existence, it ensures that:

1. The proposal has ended (state is “closed”).
2. The specified choice has received the highest score (i.e., it won the vote).

If these conditions are met, it triggers a fulfillment on the Powers contract. Like Snapshot_CheckSnapExists, the current implementation acts purely as an oracle and does not execute downstream actions upon fulfillment.

Configuration

When adopting a Snapshot_CheckSnapPassed instance, the following parameters are required:

1. spaceId (string): The Snapshot Space ID (e.g., “yam.eth”).
2. subscriptionId (uint64): The Chainlink Functions subscription ID.
3. gasLimit (uint32): The gas limit for the Chainlink Functions callback.
4. donID (bytes32): The Chainlink DON (Decentralized Oracle Network) ID.

Usage

Proposing an Action

When calling the mandate, the following parameters must be provided:

1. proposalId (string): The ID of the Snapshot proposal to verify.
2. choice (string): The voting choice to check for (e.g., “Yes”).
3. targets (address[]): (Unused) Intended for future execution logic.
4. values (uint256[]): (Unused) Intended for future execution logic.
5. calldatas (bytes[]): (Unused) Intended for future execution logic.
6. govDescription (string): A description of the governance action.

Execution Flow

1. Request Initiation (handleRequest)

   • Prepares arguments for the Chainlink Function: proposalId and choice.
   • Initiates the request to the Chainlink Oracle.

2. Oracle Call (_externalCall)

   • Sends the request to Chainlink.
   • The off-chain script queries https://hub.snapshot.org/graphql to fetch proposal details and scores.

3. Verification & Fulfillment (fulfillRequest)

   • Off-Chain Checks:
     • Does the proposal exist?
     • Is the state “closed”?
     • Does the choices array include the requested choice?
     • Does the choice have the highest score in scores?
   • On-Chain Verification:
     • Receives the result (“true” or error message).
     • If “true”, calls powers.fulfill.
   • Note: The current implementation executes fulfill with empty action arrays.

Technical Specifications

Chainlink Source

The mandate uses a hardcoded JavaScript source to query the Snapshot API:

// ...
if (snapshotData.proposal.state != "closed") return Functions.encodeString("Vote not closed.");
// ...
const maxScore = Math.max(...snapshotData.proposal.scores)
if (maxScore != snapshotData.proposal.scores[index]) return Functions.encodeString("Choice did not pass.");
return Functions.encodeString("true");

Functions

initializeMandate

function initializeMandate(
    uint16 index,
    string memory nameDescription,
    bytes memory inputParams,
    bytes memory config
) public override

• Initializes Chainlink configuration.
• Sets input parameters.

handleRequest

function handleRequest(...) public view virtual override returns (...)

• Prepares Chainlink request arguments.

fulfillRequest

function fulfillRequest(bytes32 requestId, bytes memory response, bytes memory err) internal override

• Callback from Chainlink.
• Verifies response is “true”.
• Calls powers.fulfill.

Error Conditions

1. Chainlink Errors

   • “Proposal not recognised.”
   • “Vote not closed.”
   • “Choice not present.”
   • “Choice did not pass.”
   • “Request failed” (API error).

2. Validation Errors

   • “No response from the API”
   • “Request not found”

Current Deployments

Chain ID	Chain Name	Address