xumm-sdk-py 1.0.3

Xumm SDK for Python

XUMM SDK (Python)

Interact with the XUMM SDK from Python environments.

⚠️ Please note: The XUMM SDK (XUMM API in general) is for BACKEND USE only. Please DO NOT use your API credentials in a FRONTEND environment.

To implement the XUMM SKD (or XUMM API directly) in your own web project, make sure your frontend calls your own backend, where the follow up communication with the XUMM SDK (or XUMM API) will take place. Your XUMM credentials should never be publicly available.

• Getting Started
• Usage
  • Payloads
  • App Storage
  • Helper Methods
• Development

Getting Started

Installation

Via pip:

pip3 install xumm-sdk-py

Usage

import xumm

sdk = xumm.XummSdk()
# Or with manually provided credentials (instead of using dotenv):
sdk = xumm.XummSdk('XUMM_APIKEY', 'XUMM_APISECRET')

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)

The SDK will look in your environment or dotenv file (.env) for the XUMM_APIKEY and XUMM_APISECRET values. A sample dotenv can be found here. Alternatively you can provide your XUMM API Key & Secret by passing them to the XummSdk constructor.

NOTE: If both your environment and the SDK constructor contain credentials, the values provided to the constructor will be used.

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:

payload = {
  '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 (PY 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

sdk.payload.get(
  payload: Union[str, CreatedPayload]
): -> XummPayload

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

  payload = sdk.payload.get('aaaaaaaa-bbbb-cccc-dddd-1234567890ab')
  

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

  new_payload: xumm_types.created_payload = {txjson: {...}}
  created = sdk.payload.create(new_payload)
  payload = sdk.payload.get(created)
  

sdk.payload.get('aaaaaaaa-bbbb-cccc-dddd-1234567890ab')

sdk.payload.create

sdk.payload.create (
payload: create_payload
): -> Union[CreatedPayload, None]

To create a payload, a txjson XRPL transaction can be provided. Alternatively, a transaction formatted as HEX blob (string) can be provided in a txblob property. See the intro for more information about payloads. Take a look at the Developer Docs for more information about payloads.

The response (see: Developer Docs) of a sdk.payload.create() operation, a <CreatedPayload> json object, looks like this:

{
  "uuid": "1289e9ae-7d5d-4d5f-b89c-18633112ce09",
  "next": {
    "always": "https://xumm.app/sign/1289e9ae-7d5d-4d5f-b89c-18633112ce09",
    "no_push_msg_received": "https://xumm.app/sign/1289e9ae-7d5d-4d5f-b89c-18633112ce09/qr"
  },
  "refs": {
    "qr_png": "https://xumm.app/sign/1289e9ae-7d5d-4d5f-b89c-18633112ce09_q.png",
    "qr_matrix": "https://xumm.app/sign/1289e9ae-7d5d-4d5f-b89c-18633112ce09_q.json",
    "qr_uri_quality_opts": ["m", "q", "h"],
    "websocket_status": "wss://xumm.app/sign/1289e9ae-7d5d-4d5f-b89c-18633112ce09"
  },
  "pushed": true
}

The next.always URL is the URL to send the end user to, to scan a QR code or automatically open the XUMM app (if on mobile). If a user_token has been provided as part of the payload data provided to sdk.payload.create(), you can see if the payload has been pushed to the end user. A button "didn't receive a push notification" could then take the user to the next.no_push_msg_received URL.

Alternatively user routing / instruction flows can be custom built using the QR information provided in the refs object, and a subscription for live status updates (opened, signed, etc.) using a WebSocket client can be setup by conneting to the refs.websocket_status URL. Please note: this SDK already offers subscriptions. There's no need to setup your own WebSocket client, see Payload subscriptions: live updates. There's more information about the payload workflow and a payload lifecycle in the Developer Docs.

sdk.payload.cancel

sdk.payload.cancel(
  payload: Union[str, XummPayload, CreatedPayload]
): -> Union[DeletedPayload, None]

To cancel a payload, provide a payload UUID (string), a <XummPayload> (by performing a sdk.payload.get() first) or a <CreatedPayload> (by using the response of a sdk.payload.create() call). By cancelling an existing payload, the payload will be marked as expired and can no longer be opened by users.

Please note: if a user already opened the payload in XUMM APP, the payload cannot be cancelled: the user may still be resolving the payload in the XUMM App, and should have a chance to complete that process.

A response (generic API types here) looks like:

response.result.cancelled  # bool
response.result.reason  # XummCancelReason
response.meta  # XummPayloadMeta
response.custom_meta  # XummCustomMeta

Payload subscriptions: live updates

To subscribe to live payload status updates, the XUMM SDK can setup a WebSocket connection and monitor live status events. Emitted events include:

• The payload is opened by a XUMM App user (webpage)
• The payload is opened by a XUMM App user (in the app)
• Payload expiration updates (remaining time in seconds)
• The payload was resolved by rejecting
• The payload was resolved by accepting (signing)

More information about the status update events & sample event data can be found in the Developer Docs.

Status updates can be processed by providing a callback function to the sdk.payload.subscribe() method. Alternatively, the (by the sdk.payload_subscribe() method) returned raw websocket can be used to listen for WebSocket onmessage events.

The subscription will be closed by either:

• Returning non-void in the callback function passed to the sdk.payload.subscribe() method
• Manually calling <PayloadSubscription>.resolve() on the object returned by the sdk.payload.subscribe() method

sdk.payload.subscribe

sdk.payload.subscribe(
  payload: Union[str, XummPayload, CreatedPayload],
  callback: on_payload_event
): -> PayloadSubscription

If a callback function is not provided, the subscription will stay active until the <PayloadSubscription>.resolve() method is called manually, eg. based on handling <PayloadSubscription>.websocket.onmessage events.

When a callback function is provided, for every paylaod specific event the callback function will be called with <SubscriptionCallbackParams>. The <SubscriptionCallbackParams>.data property contains parsed JSON containing event information. Either by calling <SubscriptionCallbackParams>.resolve() or by returning a non-void value in the callback function the subscription will be ended, and the <PayloadSubscription>.resolved promise will resolve with the value returned or passed to the <SubscriptionCallbackParams>.resolve() method.

Resolving (by returning non-void in the callback or calling resolve() manually) closes the WebSocket client the XUMM SDK sets up 'under the hood'.

The <PayloadSubscription> object looks like this:

response.payload  # XummPayload
response.resolved  # Union[CallbackPromise, None]
response.resolve  # CallbackPromise
response.websocket  # WSClient

Examples:

• Async process after returning data in the callback function
• Await based on returning data in the callback function
• Await based on resolving a callback event
• Await based on resolving without using a callback function

sdk.payload.create_subscribe

sdk.payload.create_and_subscribe(
  payload: CreatePayload,
  callback: on_payload_event
): -> PayloadAndSubscription

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

All information that applies on sdk.payload.create() and sdk.payload.create_and_subscribe() applies. Differences are:

1. The input for a sdk.payload.create_and_subscribe() call isn't a payload UUID / existing payload, but a paykiad to create.
2. The response object also contains (<PayloadAndSubscription>.created) the response obtained when creating the payload

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).

storage_set = await sdk.storage.set({'name': 'Wietse', 'age': 32, 'male': True})
print(storage_set)
# True

storage_get = sdk.storage.get()
print(storage_get.data)
# { 'name': 'Wietse', 'age': 32, 'male': True }

storage_delete = sdk.storage.delete()
print(storage_delete)
# True

storage_get_after_delete = sdk.storage.get()
print(storage_get_after_delete.data)
# None

Helper methods

sdk.ping()

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

pong = sdk.ping()

Returns <ApplicationDetails>:

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

sdk.get_curated_assets()

The get_curated_assets 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.

curated_assets = sdk.get_curated_assets()

Returns <CuratedAssetsResponse>:

curated_assets.issuers  # [ 'Bitstamp', 'GateHub' ]
curated_assets.currencies  # [ 'USD', 'BTC', 'EUR', 'ETH' ]
curated_assets.details.Bitstamp   # {}
curated_assets.details.GateHub   # {}

sdk.get_kyc_status()

The get_kyc_status return the KYC status of a user based on a user_token, issued after the user signed a Sign Request (from your app) before (see Payloads - Intro).

If a user token specified is invalid, revoked, expired, etc. the method will always return NONE, just like when a user didn't go through KYC. You cannot distinct a non-KYC'd user from an invalid token.

Alternatively, KYC status can be retrieved for an XPRL account address: the address selected in XUMM when the session KYC was initiated by.

kyc_status = sdk.get_kyc_status('00000000-0000-0000-0000-000000000000')

... or using an account address:

kyc_status = sdk.get_kyc_status('rwu1dgaUq8DCj3ZLFXzRbc1Aco5xLykMMQ')

Returns <str of PossibleKycStatuses>.

Notes on KYC information

• Once an account has successfully completed the XUMM KYC flow, the KYC flag will be applied to the account even if the identity document used to KYC expired. The flag shows that the account was once KYC'd by a real person with a real identity document.
• Please note that the KYC flag provided by XUMM can't be seen as a "all good, let's go ahead" flag: it should be used as one of the data points to determine if an account can be trusted. There are situations where the KYC flag is still True, but an account can no longer be trusted. Eg. when account keys are compromised and the account is now controlled by a 3rd party. While unlikely, depending on the level of trust required for your application you may want to mitigate against these kinds of fraud.

sdk.get_transaction()

The get_transaction method allows you to get the transaction outcome (mainnet) live from the XRP ledger, as fetched for you by the XUMM backend.

Note: it's best to retrieve these results yourself instead of relying on the XUMM platform to get live XRPL transaction information! You can use the xrpl-py package to do this:

tx_info = sdk.get_transaction(tx_hash)

Returns: <XrplTransaction>.

sdk.verify_user_tokens() / sdk.verify_user_tokens()

The verify_user_tokens (or single token: verify_user_token) method allows you to verify one or more User Tokens obtained from previous sign requests. This allows you to detect if you will be able to push your next Sign Request to specific users.

some_token = '691d5ae8-968b-44c8-8835-f25da1214f35'
token_validity = sdk.verify_user_tokens([
  some_token,
  'b12b59a8-83c8-4bc0-8acb-1d1d743871f1',
  '51313be2-5887-4ae8-9fda-765775a59e51'
])
if sdk.verify_user_token(some_token).active:
  # Push, use `user_token` in payload
else:
  # QR or Redirect (deeplink) flow

Returns: <UserTokenValidity or [UserTokenValidity]>.

Development

Install requirments

pip install -e ".[develop]"

Build

Please note: at least Python version 3.6+ is required!

To build the code, run python setup.py install.

Debugging

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:

python3 main.py

Example:

DEBUG=xumm-sdk* python3 main.py

Lint & test

Lint the code using:

python3 -m flake8

For running tests:

python3 test.py tests/