squid-js/src/brizo/Brizo.ts

import * as fs from 'fs'

import { File } from '../ddo/MetaData'
import Account from '../ocean/Account'
import { noZeroX } from '../utils'
import { Instantiable, InstantiableConfig } from '../Instantiable.abstract'
import save = require('save-file')

const apiPath = '/api/v1/brizo/services'

/**
 * Provides a interface with Brizo.
 * Brizo is the technical component executed by the Publishers allowing to them to provide extended data services.
 */
export class Brizo extends Instantiable {
    private get url() {
        return this.config.brizoUri
    }

    constructor(config: InstantiableConfig) {
        super()
        this.setInstanceConfig(config)
    }

    public async getVersionInfo() {
        return await (await this.ocean.utils.fetch.get(this.url)).json()
    }

    public getPurchaseEndpoint() {
        return `${this.url}${apiPath}/access/initialize`
    }

    public getConsumeEndpoint() {
        return `${this.url}${apiPath}/consume`
    }

    public getEncryptEndpoint() {
        return `${this.url}${apiPath}/publish`
    }

    public getComputeEndpoint(
        pubKey: string,
        serviceId: string,
        algo: string,
        container: string
    ) {
        // tslint:disable-next-line
        return `${this.url}${apiPath}/compute`
    }

    public async initializeServiceAgreement(
        did: string,
        serviceAgreementId: string,
        serviceDefinitionId: string,
        signature: string,
        consumerAddress: string
    ): Promise<any> {
        const args = {
            did,
            serviceAgreementId,
            serviceDefinitionId,
            signature,
            consumerAddress
        }

        try {
            return await this.ocean.utils.fetch.post(
                this.getPurchaseEndpoint(),
                decodeURI(JSON.stringify(args))
            )
        } catch (e) {
            this.logger.error(e)
            throw new Error('HTTP request failed')
        }
    }

    public async consumeService(
        agreementId: string,
        serviceEndpoint: string,
        account: Account,
        files: File[],
        destination: string,
        index: number = -1
    ): Promise<string> {
        const signature =
            (await account.getToken()) ||
            (await this.ocean.utils.signature.signText(
                noZeroX(agreementId),
                account.getId()
            ))
        const filesPromises = files
            .filter(({}, i) => index === -1 || i === index)
            .map(async ({ index: i }) => {
                let consumeUrl = serviceEndpoint
                consumeUrl += `?index=${i}`
                consumeUrl += `&serviceAgreementId=${noZeroX(agreementId)}`
                consumeUrl += `&consumerAddress=${account.getId()}`
                consumeUrl += `&signature=${signature}`

                try {
                    await this.downloadFile(consumeUrl, destination)
                } catch (e) {
                    this.logger.error('Error consuming assets')
                    this.logger.error(e)
                    throw e
                }
            })
        await Promise.all(filesPromises)
        return destination
    }

    public async encrypt(
        did: string,
        signature: string,
        document: any,
        publisher: string
    ): Promise<string> {
        const args = {
            documentId: did,
            signature,
            document: JSON.stringify(document),
            publisherAddress: publisher
        }

        try {
            const response = await this.ocean.utils.fetch.post(
                this.getEncryptEndpoint(),
                decodeURI(JSON.stringify(args))
            )
            if (!response.ok) {
                throw new Error('HTTP request failed')
            }
            return await response.text()
        } catch (e) {
            this.logger.error(e)
            throw new Error('HTTP request failed')
        }
    }

    private async downloadFile(
        url: string,
        destination?: string
    ): Promise<string> {
        const response = await this.ocean.utils.fetch.get(url)
        if (!response.ok) {
            throw new Error('Response error.')
        }
        let filename
        try {
            filename = response.headers
                .get('content-disposition')
                .match(/attachment;filename=(.+)/)[1]
        } catch {
            throw new Error('Response is not containing file name.')
        }

        if (destination) {
            await new Promise(async (resolve, reject) => {
                fs.mkdirSync(destination, { recursive: true })
                const fileStream = fs.createWriteStream(
                    `${destination}${filename}`
                )
                response.body.pipe(fileStream)
                response.body.on('error', reject)
                fileStream.on('finish', resolve)
            })

            return destination
        } else {
            save(await response.arrayBuffer(), filename)
        }
    }
}