# PAX D135 iOS Quickstart

This guide shows how to build in-person payment flows on iOS using the Finix iOS SDK with the PAX D135 Bluetooth card reader.

## Environment Designation

When ordering a PAX D135 your Finix point of contact will have you designate which environment you wish to use it in. Finix will notify you which device serial number corresponds to each environment.

### Device Designation

A D135 device can be designated to be used for either Sandbox development or Production transaction processing **but not both**. We recommend requesting enough devices to utilize in both your Sandbox development and Production testing.

## Prerequisites

- Your PAX D135 device is fully charged.
- iOS 18.1 or higher.

### Charging the Device

Charge the battery only with PAX-approved power supplies. Using others may damage the product and void the warranty.

Charging time must not exceed 24 hours. If the battery is empty, recharge it fully, then disconnect the device to avoid shortening its life.

## Determine Which Type of Integration You Prefer

The SDK supports the use of either `ROLE_PARTNER` or `ROLE_MERCHANT` credentials. If you would like to scope your device to a single merchant it is recommended to use `ROLE_MERCHANT` credentials. If you plan to use the device across multiple merchants you should use `ROLE_PARTNER` credentials.

Note that the following functionality requires the use of `ROLE_PARTNER` credentials.

- [Split Transactions](https://docs.finix.com/guides/online-payments/payment-features/split-transactions)

### How to Create ROLE_MERCHANT Credentials

The following outlines how to create `ROLE_MERCHANT` credentials. Once created, you can use these credentials across multiple devices as long as the devices are associated to the same Merchant.

**Request**

```plaintext
POST /identities
```

- Sandbox server
  https://finix.sandbox-payments-api.com/identities

**cURL**

```bash
curl -i -X POST \
  -u USfdccsr1Z5iVbXDyYt7hjZZ:313636f3-fac2-45a7-bff7-a334b93e7bda \
  https://finix.sandbox-payments-api.com/identities \
  -H 'Content-Type: application/json' \
  -H 'Finix-Version: 2022-02-01' \
  -d '{
    "additional_underwriting_data": {
      "annual_ach_volume": 0,
      "average_ach_transfer_amount": 0,
      "average_card_transfer_amount": 0,
      "business_description": "string",
      "card_volume_distribution": {
        "card_present_percentage": 0,
        "ecommerce_percentage": 0,
        "mail_order_telephone_order_percentage": 0
      },
      "credit_check_allowed": true,
      "credit_check_ip_address": "string",
      "credit_check_timestamp": "string",
      "credit_check_user_agent": "string",
      "merchant_agreement_accepted": true,
      "merchant_agreement_ip_address": "string",
      "merchant_agreement_timestamp": "string",
      "merchant_agreement_user_agent": "string",
      "refund_policy": "MERCHANDISE_EXCHANGE_ONLY",
      "volume_distribution_by_business_type": {
        "business_to_business_volume_percentage": 0,
        "business_to_consumer_volume_percentage": 0,
        "consumer_to_consumer_volume_percentage": 0,
        "other_volume_percentage": 0,
        "person_to_person_volume_percentage": 0
      }
    },
    "identity_roles": [
      "SELLER"
    ],
    "type": "BUSINESS"
  }'
```

### How to Create ROLE_PARTNER Credentials

1. Login to the Finix dashboard.
2. Select the environment for which you would like to create the api credentials (Sandbox or Live)
3. In the bottom left hand corner select the `Developer` section
4. In the Api Keys section. Select `Create Api Key`

## Creating a Device Resource

Creating a device resource can be done either via the Finix dashboard or via API. Below are the steps for creating a device via API.

### Step 1: Create a Device

Create a `Device` under the `Merchant` provisioned to process In-Person Payments. Include the `Device.model` of the payment terminal you'll be using to process cards.

**Request**

```bash
curl -i -X POST \
  -u USfdccsr1Z5iVbXDyYt7hjZZ:313636f3-fac2-45a7-bff7-a334b93e7bda \
  https://finix.sandbox-payments-api.com/merchants/MUwfZPNW3r4EqLMzwgr6txw4/devices \
  -H 'Accept: application/hal+json' \
  -H 'Content-Type: application/json' \
  -d '{
    "description": "Cashier Three",
    "model": "PAX_D135",
    "name": "My PAX_D135 Finix Device",
    "serial_number": "19046260947"
  }'
```

## Using the SDK

### Installation

Add the [SDK](https://github.com/finix-payments/finix-pax-mpos-ios-sdk) to your project via Swift Package Manager.

**Initialization**

```swift
import PaxMposSDK

let finixClient = FinixClient(config: FinixConfig(
            environment: TEST_ENVIRONMENT,
            credentials: Finix.APICredentials(username: TEST_USERNAME, password: TEST_PASSWORD),
            application: TEST_APPLICATION,
            version: TEST_VERSION,
            merchantId: TEST_MERCHANT_ID,
            mid: TEST_MERCHANT_MID,
            deviceType: .Pax,
            deviceId: ""
))
finixClient.delegate = self
finixClient.interactionDelegate = self
```

### Start Transaction

To start a transaction, first update the client with the Finix device ID (DVxxxx). Then call the function `startTransaction()`.

```swift
finixClient.update(deviceId: "DVxxxxx")

let transactionAmount = Currency(amount: Int(amountDouble * 100), code: .USD)
finixClient.startTransaction(amount: transactionAmount, type: transactionType, splitTransfers: [SplitTransfer]? = nil, tags: ResourceTags? = nil, buyerIdentityId: String? = nil) { transferResponse, error in
    // Handle using transferResponse and error
}
```

### Referenced Refund

A referenced refund, refunds the amount specified (refund amount) of a particular transaction (transaction id) to the card on file.

```swift
func startRefund(transactionID: String, amount: Currency, completion: ((RefundResponse?, Error?) -> Void)?) {
    // Implement refund logic here
}
```

### Troubleshooting with the Finix D135 Sample App

If you encounter issues with a PAX D135 while using the SDK you can reach out to the Finix Support Team at [support@finix.com](mailto:support@finix.com).  A [sample app](https://github.com/finix-payments/finix-pax-mpos-ios-sdk-demo-app) showing how to integrate the iOS D135 SDK can be found here.