vc-notarization/lib/notarization/iota.js

Notarize verifiable credentials on DLT for provability and order

import { MAX_INDEXATION_KEY_LENGTH, retrieveData, sendData, SingleNodeClient } from "@iota/iota.js";
import { Converter } from "@iota/util.js";
import { DLT } from '../enums.js';
const client = new SingleNodeClient(process.env.IOTA_NODE_URL || "https://chrysalis-nodes.iota.org");
/**
 * Converts the index string into bytes and trims it if necessary
 * @param index
 * @returns
 */
function getIndexBytes(index) {
    const indexBytes = Converter.utf8ToBytes(index);
    if (indexBytes.length > MAX_INDEXATION_KEY_LENGTH)
        return indexBytes.subarray(0, MAX_INDEXATION_KEY_LENGTH);
    return indexBytes;
}
export class Iota {
    dlt = DLT.IOTA;
    explorerURL = process.env.IOTA_EXPLORER_URL || "https://explorer.iota.org/mainnet/message/";
    async notarizeHash(hash, index) {
        const indexBytes = getIndexBytes(index || hash);
        const sendResult = await sendData(client, indexBytes, Converter.utf8ToBytes(hash));
        return {
            dlt: this.dlt,
            transactionId: sendResult.messageId,
            explorerURL: this.explorerURL + sendResult.messageId
        };
    }
    async getNotarizedTimestamp(hash, index, proof) {
        const indexBytes = getIndexBytes(index || hash);
        const messages = await client.messagesFind(indexBytes);
        if (messages && messages.messageIds.length > 0) {
            const firstOccurance = await retrieveData(client, messages.messageIds[0]);
            if (!firstOccurance || !firstOccurance.data)
                throw new Error('Could not retrieve any message data from the tangle!');
            if (Converter.bytesToUtf8(firstOccurance.data) !== hash)
                throw new Error('Notarized hash does not match the given hash!');
            const firstOccuranceMeta = await client.messageMetadata(messages.messageIds[0]);
            if (!firstOccuranceMeta)
                throw new Error('Could not retrieve any message meta data from the tangle!');
            if (!firstOccuranceMeta.isSolid)
                throw new Error('Notarization message is not solid!');
            if (!firstOccuranceMeta.referencedByMilestoneIndex)
                throw new Error('Notarization message was not referenced by a milestone!');
            const milestone = await client.milestone(firstOccuranceMeta.referencedByMilestoneIndex);
            return new Date(milestone.timestamp * 1000);
        }
        throw new Error('Could not retrieve any message from the tangle!');
    }
    async getStatus() {
        return {
            node: await client.info(),
            health: await client.health(),
        };
    }
}