Listen to events

The events defined in the Relation Protocol are completely inherited from EIP6239, we need to listen to all events that comply with the EIP6239 specifications:

/**
 * @title Semantic Soulbound Token
 * Note: the EIP-165 identifier for this interface is 0xfbafb698
 */
interface ISemanticSBT {
    /**
     * @dev This emits when minting a Semantic Soulbound Token.
     * @param tokenId The identifier for the Semantic Soulbound Token.
     * @param rdfStatements The RDF statements for the Semantic Soulbound Token. An RDF statement is the statement made by an RDF triple.
     */
    event CreateRDF (
        uint256 indexed tokenId,
        string rdfStatements
    );
    /**
     * @dev This emits when updating the RDF data of Semantic Soulbound Token. RDF data is a collection of RDF statements that are used to represent information about resources.
     * @param tokenId The identifier for the Semantic Soulbound Token.
     * @param rdfStatements The RDF statements for the semantic soulbound token. An RDF statement is the statement made by an RDF triple.
     */
    event UpdateRDF (
        uint256 indexed tokenId,
        string rdfStatements
    );
    /**
     * @dev This emits when burning or revoking Semantic Soulbound Token.
     * @param tokenId The identifier for the Semantic Soulbound Token.
     * @param rdfStatements The RDF statements for the Semantic Soulbound Token. An RDF statement is the statement made by an RDF triple.
     */
    event RemoveRDF (
        uint256 indexed tokenId,
        string rdfStatements
    );
    /**
     * @dev Returns the RDF statements of the Semantic Soulbound Token. An RDF statement is the statement made by an RDF triple.
     * @param tokenId The identifier for the Semantic Soulbound Token.
     */
    function rdfOf(uint256 tokenId) external view returns (string memory);
}

• CreateRDF: Triggered when a SBT containing RDF semantics is created.

• UpdateRDF: Triggered when a SBT containing RDF semantics is updated.

• RemoveRDF: Triggered when a SBT containing RDF semantics is removed.

By listening to these events on the blockchain, you will receive RDF data containing semantics (code 7-1), which contains user behavior data.

code 7-1

:Soul_0x0109c8ee3151bde7b6b5d9f37e9d2c4bc16930fe p:following :Soul_0x6247123ec0fe0d25feb811e3c4d4a760c1f2e63e .

Use The Graph index

With The Graph, we can index users' behavioral data on the blockchain easily. You can refer to The Graph documentation.

Below is the behavioral data from the Polygon network through our listening. The address is:

https://thegraph.com/hosted-service/subgraph/relationlabs/semantic-sbt

• Query via the playground provided by The Graph:

Figure 7-2 Query via the playground

• Query via the GraphQL API provided by The Graph:

eg. To query the latest two token records:

curl --location --request POST 'https://api.thegraph.com/subgraphs/name/relationlabs/semantic-sbt' \
--header 'Content-Type: application/json' \
--data-raw '{"query":"{\n  turtles(first: 2) {\n    id\n    owner\n    tokenId\n    turtle\n  }\n}"}'

The result

{"data":{"turtles":[{"id":"33456276423","owner":"0x16ff7821a8d293cd2ea07b650fc69ea9206d0615","tokenId":"1","turtle":":Activity1 p:name \"Activity_2049_1\" . :Activity1 p:level 1 . "},{"id":"33456276425","owner":"0x16ff7821a8d293cd2ea07b650fc69ea9206d0615","tokenId":"2","turtle":":Activity2 p:name \"Activity_2049_2\" . :Activity2 p:level 2 . "}]}}

Use The ethers.js

ethers.js is a JavaScript library for interacting with the Ethereum Blockchain and its ecosystem.

For example:

const ethers = require('ethers')
const rpc = 'https://polygon-mumbai.blockpi.network/v1/rpc/public'
let abi = ['event CreateRDF(uint256 indexed tokenId, string rdfStatements)']
const provider = new ethers.JsonRpcProvider(rpc)
const iface = new ethers.Interface(abi)
const filter = {}

// listen
provider.on(filter, (e) => {
  try {
    let event = iface.parseLog(e)
    console.log(event)
    // parse ...
  } catch (error) {}
})