squid-js/src/ocean/Order.ts

import * as EthCrypto from "eth-crypto"
import EthEcies from "eth-ecies"
import * as EthjsUtil from "ethereumjs-util"
import JWT from "jsonwebtoken"
import Keeper from "../keeper/Keeper"
import Asset from "../models/Asset"
import OrderModel from "../models/Order"
import Logger from "../utils/Logger"

declare var fetch

export default class Order {

    private static create(asset: Asset, args, key): OrderModel {
        Logger.log("keeper AccessConsentRequested event received on asset: ", asset.assetId, "\nevent:", args)
        const accessId = args._id
        Logger.log("got new access request id: ", accessId)
        return {
            id: accessId,
            assetId: asset.assetId,
            asset,
            timeout: args._timeout,
            pubkey: args._pubKey,
            key,
        } as OrderModel
    }

    private keeper: Keeper

    constructor(keeper: Keeper) {
        this.keeper = keeper
    }

    public async getOrdersByConsumer(consumerAddress: string) {
        const {auth, market} = this.keeper

        const accessConsentRequestedData = await auth.getEventData("AccessConsentRequested", {
            filter: {
                _consumer: consumerAddress,
            },
            fromBlock: 0,
        })

        Logger.log("wai", accessConsentRequestedData)

        const orders = await Promise.all(
            accessConsentRequestedData
                .filter((event: any) => (event.args._consumer === consumerAddress))
                .map(async (event: any) => ({
                            ...event.args,
                            timeout: event.args._timeout.toNumber(),
                            status: await auth.getOrderStatus(event.args._id),
                            paid: await market.verifyOrderPayment(event.args._id),
                            key: null,
                        } as Order
                    ),
                ),
        )

        Logger.log("Got orders: ", orders)
        return orders
    }

    public async purchaseAsset(asset: Asset, timeout: number, buyerAddress: string): Promise<OrderModel> {
        const {token, market, auth} = this.keeper

        const key = EthCrypto.createIdentity()
        const publicKey = EthjsUtil.privateToPublic(key.privateKey).toString("hex")
        const price = await market.getAssetPrice(asset.assetId)
        const isValid = await market.isAssetActive(asset.assetId)

        Logger.log("The asset:", asset.assetId, "is it valid?", isValid, "it's price is:", price)

        if (!isValid) {
            throw new Error("asset not valid")
        }
        try {
            // Allow market contract to transfer funds on the consumer"s behalf
            await token.approve(market.getAddress(), price, buyerAddress)
        } catch (err) {
            Logger.log("token approve", err)
        }
        try {
            // Submit the access request
            await auth.initiateAccessRequest(asset, publicKey, timeout, buyerAddress)
        } catch (err) {
            Logger.log("initiateAccessRequest", err)
        }

        let order: OrderModel
        const finalOrder: OrderModel = await auth.listenToEventOnce(
            "AccessConsentRequested", {
                filter: {
                    _resourceId: asset.assetId,
                    _consumer: buyerAddress,
                },
            })
            .then((accessConsentRequestedResult) => {
                order = Order.create(asset, accessConsentRequestedResult.args, key)

                return auth.listenToEventOnce("AccessRequestCommitted", {
                    filter: {
                        _id: order.id,
                    },
                })
            })
            .then((accessRequestCommittedResult) => {
                return this.payAsset(asset, accessRequestCommittedResult.args, order, buyerAddress)
            })
            .then(() => {
                return auth.listenToEventOnce("EncryptedTokenPublished", {
                    filter: {
                        _id: order.id,
                    },
                })
            })
            .then((result) => {
                return this.finalizePurchaseAsset(
                    result, order, key, buyerAddress,
                )
            })

        return finalOrder
    }

    private async payAsset(asset: Asset, args, order, buyerAddress) {
        const {market} = this.keeper

        // send payment
        Logger.log("Sending payment: ", order.id, args._id, asset.publisherId, asset.price, order.timeout)
        return market.payAsset(asset, order, buyerAddress)
    }

    private async finalizePurchaseAsset(args, order, key, buyerAddress): Promise<OrderModel> {
        const {auth, web3Helper} = this.keeper

        // Logger.log('keeper EncryptedTokenPublished event received: ', order.id, eventResult.args)

        const encryptedAccessToken = await auth.getEncryptedAccessToken(args._id, buyerAddress)

        // grab the access token from acl contract
        const tokenNo0x = encryptedAccessToken.slice(2)
        const encryptedTokenBuffer = Buffer.from(tokenNo0x, "hex")

        const privateKey = key.privateKey.slice(2)
        const accessTokenEncoded = EthEcies.Decrypt(Buffer.from(privateKey, "hex"), encryptedTokenBuffer)
        const accessToken = JWT.decode(accessTokenEncoded) // Returns a json object

        // sign it
        const hexEncrToken = `0x${encryptedTokenBuffer.toString("hex")}`

        const signature = web3Helper.sign(buyerAddress, hexEncrToken)
        const fixedMsgSha = web3Helper.getWeb3().utils.sha3(encryptedAccessToken)

        // Download the data set from the provider using the url in the access token
        // decode the access token, grab the service_endpoint, request_id,

        // payload keys: ['consumerId', 'fixed_msg', 'sigEncJWT', 'jwt']
        const payload = JSON.stringify({
            consumerId: buyerAddress,
            fixed_msg: fixedMsgSha,
            sigEncJWT: signature,
            jwt: accessTokenEncoded,
        })
        const accessUrl = await fetch(`${accessToken.service_endpoint}/${accessToken.resource_id}`, {
            method: "POST",
            body: payload,
            headers: {
                "Content-type": "application/json",
            },
        })
            .then((response: any) => {
                if (response.ok) {
                    return response.text()
                }
                Logger.log("Failed: ", response.status, response.statusText)
            })
            .then((consumptionUrl: string) => {
                Logger.log("Success accessing consume endpoint: ", consumptionUrl)
                return consumptionUrl
            })
            .catch((error) => {
                Logger.error("Error fetching the data asset consumption url: ", error)
            })
        Logger.log("consume url: ", accessUrl)
        order.accessUrl = accessUrl

        return order
    }
}