@amag-ch/sap_cap_common_objectstore/lib/Service.js

NodeJS library to communicate with an objectstore

const cds = require('@sap/cds')
const Client = require('./clients/Client')
const Persistance = require('./Persistance')
const { ObjectNotFound } = require('./errors')

const DEBUG = cds.debug('objectstore')

module.exports = class ObjectStoreService extends cds.Service {
    async init() {

        const persistance = await Persistance.create(this)
        // @ts-ignore
        const client = await Client.create(this.options)

        /**
         * Create a file.
         * 
         * @param {string|ReadableStream|Blob|Buffer} content
         * @param {{ filename?: string, contentType?: string, ID: string }} options
         * @returns {Promise<string>} 
         */
        this.create = async (content, { filename, contentType, ID }) => {
            if (ID)
                await persistance.delete(ID)

            ID ??= cds.utils.uuid()

            DEBUG?.(`Create new file ${ID} with original filename ${filename}`)

            await client.put(ID, content, { contentType })

            const { contentLength, modifiedAt } = await client.head(ID)

            await persistance.create({
                ID,
                filename: filename ?? ID,
                contentType,
                contentLength,
                modifiedAt: modifiedAt.toISOString()
            })

            return ID
        }

        /**
         * Delete file.
         * 
         * @param {string} ID
         * @returns {Promise<void>}
         */
        this.delete = async (ID) => {
            DEBUG?.(`Delete file ${ID}`)

            return persistance.delete(ID)
        }

        /**
         * Read file.
         * 
         * @param {string} ID
         * @returns {Promise<ReadableStream>}
         */
        this.readContent = async (ID) => {
            DEBUG?.(`Read content of file ${ID}`)

            if (!await persistance.exists(ID))
                throw new ObjectNotFound(`File with ID ${ID} not found`)

            return client.get(ID)
        }

        /**
         * @param {String} ID
         */
        this.deleteFromStore = async (ID) => {
            DEBUG?.(`Delete file ${ID} from store`)

            return client.delete(ID)
        }

        /**
         * @param {String} ID 
         * @param {string|ReadableStream|Blob|Buffer} content
         */
        this.addToStore = async (ID, content) => {
            return client.put(ID, content)
        }

        return super.init()
    }

    static testing = require('./testing')
}