XUMM SDK (JS/TS)

Interact with the XUMM SDK from Javascript / Typescript environments.

How to use the XUMM SDK

Get the SDK straight from npm: npm install xumm-sdk. The SDK is also available for Deno (XUMM SDK Deno Readme).

Initialize the SDK in Javascript:

const {XummSdk} = require('xumm-sdk')

... or in Typescript:

import {XummSdk} from 'xumm-sdk'
// Or with types:
//   import {XummSdk, XummTypes} from 'xumm-sdk'

Now continue by constructing the XummSdk object:

const Sdk = new XummSdk()
// Or with manually provided credentials (instead of using dotenv):
//   const Sdk = new XummSdk('someAppKey', 'someAppSecret')

Credentials

The SDK will look in your environment or dotenv file (.env) for the XUMM_APIKEY and XUMM_APISECRET values. A .env.sample file is provided in this repository. A sample dotenv file looks like this. Alternatively you can provide your XUMM API Key & Secret by passing them to the XummSdk constructor. If both your environment and the SDK constructor contain credentials, the values provided to the constructor will be used.

Create your app and get your XUMM API credentials at the XUMM Developer Console:

• https://apps.xumm.dev

More information about the XUMM API, payloads, the API workflow, sending Push notifications, etc. please check the XUMM API Docs:

• https://xumm.readme.io/docs

Methods & params (+ samples)

After constructing the SDK, you can call the methods:

• Sdk.* for the helper methods (see below)
• Sdk.payload.* to get/update/create payloads for users to sign
• Sdk.storage.* for your XUMM app storage (to store meta info for headless applications)

Please note all snippets below assume you constructed the XUMM SDK into the Sdk constant, as the How to use the XUMM SDK section outlines.

Helper methods

Sdk.ping()

The ping method allows you to verify API access (valid credentials) and returns some info on your XUMM APP:

const pong = await Sdk.ping()

Returns <ApplicationDetails>:

{
  quota: {},
  application: {
    uuidv4: '00000000-1111-2222-3333-aaaaaaaaaaaa',
    name: 'My XUMM APP',
    webhookurl: '',
    disabled: 0
  },
  call: { uuidv4: 'bbbbbbbb-cccc-dddd-eeee-111111111111' }
}

Sdk.getCuratedAssets()

The getCuratedAssets method allows you to get the list of trusted issuers and IOU's. This is the same list used to populate the "Add Asset" button at the XUMM home screan.

const curatedAssets = await Sdk.getCuratedAssets()

Returns <CuratedAssetsResponse>:

{
  curatedAssets: {
    issuers: [ 'Bitstamp', 'GateHub' ],
    currencies: [ 'USD', 'BTC', 'EUR', 'ETH' ],
    details: {
      Bitstamp: [Object],
      GateHub: [Object]
    }
  }
}

App Storage

App Storage allows you to store a JSON object at the XUMM API platform, containing max 60KB of data. Your XUMM APP storage is stored at the XUMM API backend, meaning it persists until you overwrite or delete it.

This data is private, and accessible only with your own API credentials. This private JSON data can be used to store credentials / config / bootstrap info / ... for your headless application (eg. POS device).

const storageSet = await Sdk.storage.set({name: 'Wietse', age: 32, male: true})
console.log(storageSet)
// true

const storageGet = await Sdk.storage.get()
console.log(storageGet)
// { name: 'Wietse', age: 32, male: true }

const storageDelete = await Sdk.storage.delete()
console.log(storageDelete)
// true

const storageGetAfterDelete = await Sdk.storage.get()
console.log(storageGetAfterDelete)
// null

Payloads

Intro

Payloads are the primary reason for the XUMM API (thus this SDK) to exist. The XUMM API Docs explain 'Payloads' like this:

An XRPL transaction "template" can be posted to the XUMM API. Your transaction tample to sign (so: your "sign request") will be persisted at the XUMM API backend. We now call it a a Payload. XUMM app user(s) can open the Payload (sign request) by scanning a QR code, opening deeplink or receiving push notification and resolve (reject or sign) on their own device.

A payload can contain an XRPL transaction template. Some properties may be omitted, as they will be added by the XUMM app when a user signs a transaction. A simple payload may look like this:

{
  txjson: {
    TransactionType : 'Payment',
    Destination : 'rwiETSee2wMz3SBnAG8hkMsCgvGy9LWbZ1',
    Amount: '1337'
  }
}

As you can see the payload looks like a regular XRPL transaction, wrapped in an txjson object, omitting the mandatory Account, Fee and Sequence properties. They will be added containing the correct values when the payload is signed by an app user.

Optionally (besides txjson) a payload can contain these properties (TS definition):

• options to define payload options like a return URL, expiration, etc.
• custom_meta to add metadata, user insruction, your own unique ID, ...
• user_token to push the payload to a user (after obtaining a user specific token)

A more complex payload could look like this. A reference for payload options & custom meta can be found in the API Docs.

Instead of providing a txjson transaction, a transaction formatted as HEX blob (string) can be provided in a txblob property.

Sdk.payload.get

async Sdk.payload.get (
  payload: string | CreatedPayload,
  returnErrors: boolean = false
): Promise<XummPayload | null>

To get payload details, status and if resolved & signed: results (transaction, transaction hash, etc.) you can get() a payload.

Note! Please don't use polling! The XUMM API offers Webhooks (configure your Webhook endpoint in the Developer Console) or use a subscription to receive live payload updates (for non-SDK users: Webhooks).

You can get() a payload by:

• Payload UUID

  const payload = await Sdk.payload.get('aaaaaaaa-bbbb-cccc-dddd-1234567890ab')

• Passing a created Payload object (see: Sdk.payload.create)

  const newPayload: XummTypes.CreatedPayload = {txjson: {...}}
  const created = await Sdk.payload.create(newPayload)
  const payload = await Sdk.payload.get(created)

If a payload can't be fetched (eg. doesn't exist), null will be returned, unless a second param (boolean) is provided to get the SDK to throw an Error in case a payload can't be retrieved:

await Sdk.payload.get('aaaaaaaa-bbbb-cccc-dddd-1234567890ab', true)

Sdk.payload.create

async Sdk.payload.create (
  payload: CreatePayload,
  returnErrors: boolean = false
): Promise<CreatedPayload | null>

WIP

Sdk.payload.cancel

async Sdk.payload.cancel (
  payload: string | XummPayload | CreatedPayload,
  returnErrors: boolean = false
): Promise<DeletedPayload | null>

WIP

Payload subscriptions: live updates

WIP

• Note: Two methods: callback + return non void = break, of return object en resolve()
  • onPayloadEvent
• Reminder: type for callback event?

Sdk.payload.subscribe

async Sdk.payload.subscribe (
    payload: string | XummPayload | CreatedPayload,
    callback?: onPayloadEvent
  ): Promise<PayloadSubscription>

The <PayloadSubscription> object looks like this:

WIP

Sdk.payload.createAndSubscribe

async Sdk.payload.createAndSubscribe (
    payload: CreatePayload,
    callback?: onPayloadEvent
  ): Promise<PayloadAndSubscription>

The <PayloadAndSubscription> object is basically a <PayloadSubscription> object with the created payload results in the created property:

WIP

Debugging (logging)

The XUMM SDK will emit debugging info when invoked with a debug environment variable configured like: DEBUG=xumm-sdk*

You'll see the XUMM SDK debug messages if you invoke your script instead of this:

node myApp.js

like this:

DEBUG=xumm-sdk* node myApp.js

Development

Please note: you most likely just want to use the XUMM SDK, to do so, fetch the xumm-sdk package from NPM using npm install --save xumm-sdk.

If you actually want to change/test/develop/build/contribute (to) the source of the XUMM SDK:

Build

Please note: at least Typescript version 3.8+ is required!

To build the code, run tsc. To build automatically on file changes (watch): tsc -w.

Lint & test

Lint the code using npm run lint, run tests (jest) using npm run test

Run development code:

Build, run, show debug output & watch dist/samples/dev.js, compiled from samples/dev.ts using npm run dev. The samples/dev.ts file is not included by default.

Here's a sample samples/dev.ts file.