Honor Liquidity Provider Withdrawals

Learn how to honor withdrawal requests from liquidity providers.

Overview#

In the previous tutorial, you learned how you the Payment Gateway can acknowledge fund deposits into a liquidity provider’s account.

Liquidity providers may also wish to withdraw some, or all of those deposited funds. Liquidity providers may also have funds available to be withdrawn from trades done.

It is your job, you the financial institution PAPE integrator, to honor those withdrawal requests.

You do that by checking all pending withdrawals that concern your financial instititon. The relevant APIs are found below. Once you’ve found pending withdrawal requests, you process them in your own backend.

NB: Withdrawal requests DO NOT get pushed to you the integrator. You will have to continuously POLL the withdrawals endpoint to find new withdrawal requests for you to process.

Liquidity Provider Withdrawal - Data Model#

Liquidity Provider Withdrawal - API Calls#

Try it out:#

Let’s get a list of pending withdrawal requests and confirm a withdrawal.

Prerequisites#

• Interswitch should have already provided you with a liquidity provider account.

• You’ve followed the previous tutorial to deposit funds into your liquidity provider account.

• IMPORTANT: You’ve used the Liquidity Provider Dashboard UI to initiate a withdrawal request.

Tools you might need#

These are the tools you might need to follow along this tutorial.

• linux or mac: Many of the command line examples have been customized for UNIX-like operating systems.

• curl: To perform API calls.

  • mac: brew install curl
  • ubuntu/debian: sudo apt-get install curl

• jq: To process json on the command line.

  • mac: brew install jq
  • ubuntu/debian: sudo apt-get install jq

• jo: To create json on the command line.

  • mac: brew install jo
  • ubuntu/debian: sudo apt-get install jo

• openssl: To perform cryptographic operations on the command line.

  • mac: brew install openssl
  • ubuntu/debian: sudo apt-get install openssl

RSA Keys#

Depositing funds requires digital signatures as previously outlined in our Security Prologue.

To facilitate our command line operations for this tutorial, we will store our payment gateway RSA keys in special folders.

mkdir -p ~/.pape-rsa-keys

The private and public keys of each payment gateway you manage should be kept inside the above folder with the format below:

• ~/.pape-rsa-keys/paymentGatewayId.pub for the public key, and
• ~/.pape-rsa-keys/paymentGatewayId.priv for the private key

e.g.

• ~/.pape-rsa-keys/ng.bank.ecobank.ngn.pub for the public key, and
• ~/.pape-rsa-keys/ng.bank.ecobank.ngn.priv for the private key

Liquidity Provider Account#

For the purpose of this demo, you will withdraw funds from a liquidity provider you control.

Please contact Interswitch to give you a valid PAPE liquidity provider ID with credentials.

Get Token#

export PAPE_TOKEN_ENDPOINT=https://id.dev.projectwhite.io/auth/realms/projectwhite/protocol/openid-connect/token;

export PAPE_API_ENDPOINT=https://apis-alpha.dev.projectwhite.io

export PAPE_USERNAME=cm.wallet.interstellar-demo.xaf;

export PAPE_PASSWORD=abc;

export PAPE_TOKEN=`curl -s --request POST \
--url "$PAPE_TOKEN_ENDPOINT" \
--data-urlencode grant_type=password \
--data-urlencode username=$PAPE_USERNAME \
--data-urlencode password=$PAPE_PASSWORD \
--data-urlencode 'client_id=projectwhite' \
| jq -r ".access_token"`

echo $PAPE_TOKEN

Withdrawal List APIs#

# {{ base_url }}/payment-gateways/{{payment-gateway-id}}/withdrawals

curl --request GET \
  --url "https://apis-alpha.dev.projectwhite.io/payment-gateways/$PAPE_USERNAME/withdrawals?status=pending_gateway&_size=3&_sort=pagingToken.asc" \
  --header "Authorization: Bearer $PAPE_TOKEN" | jq .

Sample Response#

[
  {
    "id": "f182f3c6-58e6-454e-a002-2c2f95016372",
    "createdAt": "2021-06-04T08:22:55.0839286+01:00",
    "updatedAt": "2021-06-04T08:22:55.0839286+01:00",
    "pagingToken": "1622791370957-848514799",
    "paymentGatewayId": "cm.wallet.interstellar-demo.xaf",
    "paymentGatewayTransactionId": "",
    "amount": "1000",
    "fee": "",
    "currency": "XAF",
    "blockchainTransactionId": "dacd46d9140a899e8cb46f97eaa8cf298fb35a781a1b156feec10e2936447f58",
    "status": "pending_gateway",
    "extras": null
  },
  {
    "id": "0b2cf945-e4bb-4883-b258-4dc21927e1c2",
    "createdAt": "2021-06-04T15:16:47.5880189+01:00",
    "updatedAt": "2021-06-04T15:16:47.5880189+01:00",
    "pagingToken": "1622816207588-236698997",
    "paymentGatewayId": "cm.wallet.interstellar-demo.xaf",
    "paymentGatewayTransactionId": "",
    "amount": "1000",
    "fee": "100",
    "currency": "XAF",
    "blockchainTransactionId": "f21a0d5109cb3c0543a6b51166cb68d43bcff8b37931daad90fac4573b17f3f0",
    "status": "pending_gateway",
    "extras": null
  },
  {
    "id": "ebdb9649-3163-40c4-80bc-d82fea822bb2",
    "createdAt": "2021-06-04T21:12:43.718656+01:00",
    "updatedAt": "2021-06-04T21:12:43.718656+01:00",
    "pagingToken": "1622837563718-1133030347",
    "paymentGatewayId": "cm.wallet.interstellar-demo.xaf",
    "paymentGatewayTransactionId": "",
    "amount": "1500",
    "fee": "100",
    "currency": "XAF",
    "blockchainTransactionId": "ba6e3e24d9dda78921602dd42e7ad3a0fe0d8aae50862786aee7d237aed54958",
    "status": "pending_gateway",
    "extras": null
  }
]

Error Response#

{
  "error": "string",
  "message": "string"
}

If you receive an empty array, this means you have not yet initiated a withdrawal on the liquidity provider dashboard.

Confirm Processed Withdrawal.#

curl --request PUT \
  --url "https://apis-alpha.dev.projectwhite.io/payment-gateways/$PAPE_USERNAME/withdrawals/ebdb9649-3163-40c4-80bc-d82fea822bb2" \
  --header 'Authorization: Bearer $PAPE_TOKEN' \
  --header 'Content-Type: application/json' \
  --data '{
  "gatewayTransactionId": "'$(date +%s)'",
  "status": "processed"
}' | jq .