Curate Classic Integration

Developer guide for integrating with Kleros Curate Classic (V1 on-chain storage)

Curate Classic: Integration for Devs

This covers Curate Classic (V1) with on-chain storage. For the newer Light Curate with subgraph-based storage, see Light Curate Integration. For V2 Curate, see the Developers Curate section.

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Overview

Curate Classic is the original version of Kleros Curate. All item data (apart from files/images) is stored on-chain in contract storage. This means other contracts can query the TCR for field values directly, but deployment and operation costs are higher.

Key characteristics:

• Item data stored on-chain as encoded bytes
• Requires @kleros/gtcr-encoder to encode/decode items
• Client must sync by downloading every item and decoding it
• Higher gas costs (O(n) storage)
• Other contracts can read item fields directly

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Reading Data

Using the Subgraph

Use the items entity (not litems, which is for Light Curate):

{
  items(
    first: 10
    where: {
      status: Registered
      registryAddress: "0xYOUR_REGISTRY_LOWERCASE"
    }
  ) {
    itemID
    data
    status
  }
}

The data field contains encoded bytes. Decode using @kleros/gtcr-encoder.

Using the Encoder

npm install @kleros/gtcr-encoder

const { gtcrDecode } = require("@kleros/gtcr-encoder");
const columns = [/* column definitions from the TCR meta evidence */];
const decodedItem = gtcrDecode({ columns, values: item.data });

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Writing Data

Submitting an Item

Encode the item fields and call addItem() on the GeneralizedTCR contract with the required deposit.

Challenging an Item

Call challengeRequest() on the contract with a deposit. The challenge creates a dispute in Kleros Court.

Executing Requests

Call executeRequest() after the challenge period passes without a challenge.

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Resources

Curate Classic Contracts

Source code

Subgraph

Curate subgraph on The Graph