Frontend API

Render third-party payment elements with settings configured by your Swell store. This method dynamically loads third-party libraries such as Stripe, Braintree, and PayPal, in order to standardize the way payment details are captured.

When using a card element, it's necessary to tokenize card details before submitting an order.

Render Stripe elements to capture credit card information. You can choose between a unified card element or separate elements (cardNumber, cardExpiry, cardCvc).

In order to render a card element, you will need to fetch or initialize a cart.

Render a Stripe card element
import swell from 'swell-js'

swell.init('my-store', 'pk_...')

swell.payment.createElements({
  card: {
    elementId: '#card-element-id', // default: #card-element
    options: {
      // options are passed as a direct argument to stripe.js
      style: {
        base: {
          fontWeight: 500,
          fontSize: '16px'
        }
      }
    },
    onChange: event => {
      // optional, called when the Element value changes
    },
    onReady: event => {
      // optional, called when the Element is fully rendered
    },
    onFocus: event => {
      // optional, called when the Element gains focus
    },
    onBlur: event => {
      // optional, called when the Element loses focus
    },
    onEscape: event => {
      // optional, called when the escape key is pressed within an Element
    },
    onClick: event => {
      // optional, called when the Element is clicked
    },
    onSuccess: result => {
      // optional, called on card payment success
    },
    onError: error => {
      // optional, called on card payment error
    }
  }
})

Separate card elements

Rendering separate Stripe card elements
import swell from 'swell-js'

swell.init('my-store', 'pk_...')

swell.payment.createElements({
  card: {
    separateElements: true, // required for separate elements
    cardNumber: {
      elementId: '#card-number-id', // default: #cardNumber-element
      options: {
        // options are passed as a direct argument to stripe.js
        style: {
          base: {
            fontWeight: 500,
            fontSize: '16px'
          }
        }
      }
    },
    cardExpiry: {
      elementId: '#card-expiry-id' // default: #cardExpiry-element
    },
    cardCvc: {
      elementId: '#card-expiry-id' // default: #cardCvc-element
    }
    // events: onChange, onReady, onSuccess, onError, etc...
  }
})

iDeal

Rendering iDeal
import swell from 'swell-js'

swell.init('my-store', 'pk_...')

swell.payment.createElements({
  ideal: {
    elementId: '#ideal-element-id', // default: #idealBank-element
    options: {
      style: {
        base: {
          fontWeight: 500,
          fontSize: '16px'
        }
      }
    }
    // events: onChange, onReady, onSuccess, onError, etc...
  }
})

See Stripe documentation for more information on options and customization.

Render a PayPal checkout button.

Render a Paypal checkout button
await $swell.payment.createElements({
  paypal: {
    elementId: '#paypal-button',
    style: {
      layout: 'horizontal',
      color: 'blue',
      shape: 'rect',
      label: 'buynow',
      tagline: false,
    },
    onSuccess: () => {
      $swell.cart.submitOrder();
    },
    onError: (error) => {
      console.log('onError', error);
    },
  },
});

See PayPal documentation for details on available style parameters.

Follow these steps to use Braintree as a gateway for PayPal.

When using a payment element such as card with Stripe, it's necessary to tokenize card details before submitting a payment form. Some payment methods such as PayPal will auto-submit once the user completes authorization via PayPal, but tokenizing is always required for credit card elements.

If successful, tokenize() will automatically update the cart with relevant payment details. Otherwise, returns a validation error.

In order to tokenize successfully, there must be a product in the cart with a grand total greater than 1.

Tokenize elements
import swell from 'swell-js';

swell.init('my-store', 'pk_...');

swell.payment.createElements({
  card: {
    ...
  },
});

const form = document.getElementById('payment-form');
form.addEventListener('submit', function(event) {
  event.preventDefault();
  showLoading();

  await swell.payment.tokenize({
    card: {
      onError: (err) => {
        // inform the customer there was an error
      },
      onSuccess: () => {
        //finally submit the form
        form.submit();
      }
    }
    // ideal: { onError: (err) => {}, ...}
    // klarna: { onError: (err) => {}, ...}
    // bancontact: { onError: (err) => {}, ...}
  });

  hideLoading();
});

Some payment methods such as ideal, klarna, bancontact automatically redirect the user to the payment page to authorize the payment.

After the customer redirects back to your site after authorizing the payment or entering the payment information, it is necessary to configure the cart billing and then submit the order.

iDeal

Stripe iDeal redirect actions
import swell from 'swell-js'

swell.init('my-store', 'pk_...')

if (redirectParams.status !== 'succeeded') {
  // inform the customer there was an error
  return
}

await swell.cart.update({
  billing: {
    intent: {
      stripe: { id: '<intent_id>' }
    },
    ideal: {
      token: '<payment_method_id>'
    }
  }
})

await swell.cart.submitOrder()

Klarna

Stripe Klarna redirect actions
import swell from 'swell-js'

swell.init('my-store', 'pk_...')

if (redirectParams.status !== 'succeeded') {
  // inform the customer there was an error
  return
}

const params = await swell.cart.update({
  billing: {
    klarna: {
      source: '<source_id>'
    }
  }
})

await swell.cart.submitOrder()

Bancontact

Stripe Bancontact redirect actions
import swell from 'swell-js'

swell.init('my-store', 'pk_...')

if (redirectParams.status !== 'succeeded') {
  // inform the customer there was an error
  return
}

const params = await swell.cart.update({
  billing: {
    bancontact: {
      source: '<source_id>'
    }
  }
})

await swell.cart.submitOrder()

Card

Saferpay card reditect actions
import swell from 'swell-js'

swell.init('my-store', 'pk_...')

if (redirectParams.status !== 'succeeded') {
  // inform the customer there was an error
  return
}

const intent = await swell.payment.updateIntent({
  gateway: 'saferpay',
  intent: { token: '<saferpay_transaction_token>' }
})

if (intent.error) {
  // inform the customer there was an error
  return
}

const {
  RegistrationResult: {
    Alias: { Id: token }
  },
  PaymentMeans: {
    Card: { ExpMonth: exp_month, ExpYear: exp_year, MaskedNumber },
    Brand: { Name: brand }
  }
} = intent

const params = await swell.cart.update({
  billing: {
    card: {
      token,
      exp_month,
      exp_year,
      brand,
      last4: MaskedNumber.substring(MaskedNumber.length - 4),
      gateway: 'saferpay'
    }
  }
})

await swell.cart.submitOrder()

If a payment element isn't available for your credit card processor, you can tokenize credit card information directly.

Returns an object representing the card token. Pass the token ID to a cart's billing.card.token field to designate this card as the payment method.

Create a card token
const response = await swell.card.createToken({
  number: '4242 4242 4242 4242',
  exp_month: 1,
  exp_year: 2099,
  cvc: 321,
  // Note: some payment gateways may require a Swell `account_id` and `billing` for card verification (Braintree)
  account_id: '5c15505200c7d14d851e510f',
  billing: {
    address1: '1 Main Dr.',
    zip: 90210
    // Other standard billing fields optional
  }
})
Success and error responses for card tokenization
{
  token: 't_z71b3g34fc3',
  brand: 'Visa',
  last4: '4242',
  exp_month: 1,
  exp_year: 2029,
  cvc_check: 'pass', // fail, checked
  zip_check: 'pass', // fail, checked
  address_check: 'pass', // fail, checked
}

Returns true if the card number is valid, otherwise false.

Validate card number
swell.card.validateNumber('4242 4242 4242 4242') // => true
swell.card.validateNumber('1111') // => false

Returns true if the card expiration date is valid, otherwise false.

Validate card expiry
swell.card.validateExpiry('1/29') // => true
swell.card.validateExpiry('1/2099') // => true
swell.card.validateExpiry('9/99') // => false

Returns true if the card CVC code is valid, otherwise false.

Validate CVC code
swell.card.validateCVC('321') // => true
swell.card.validateCVC('1') // => false

After generating a card token, update the cart billing details and it will be handled according to payment settings when the order is submitted.

When using a payment element instead of direct tokenization, the cart will be automatically updated.

Add card token to cart
const response = await swell.card.createToken({
  number: '4242 4242 4242 4242',
  exp_month: 1,
  exp_year: 2099,
  cvc: 321,
  // Note: some payment gateways may require a Swell `account_id` and `billing` for card verification (Braintree)
  account_id: '5c15505200c7d14d851e510f',
  billing: {
    address1: '1 Main Dr.',
    zip: 90210
    // Other standard billing fields optional
  }
})

await swell.cart.update({
  billing: {
    card: response
  }
})

If you need more flexibility in the integration process, you can use the following guides to achieve this.

This guide describes how to integrate Klarna, iDEAL and Bancontact using Stripe sources with a custom checkout flow.

Start by connecting a Stripe account to Swell (Settings > Payments); open "Advanced options" under Stripe settings and check Enable Klarna / Enable iDEAL / Enable Bancontact.

Include Stripe.js on the payment page of your site. This can be done in two ways:

01
Load directly from https://js.stripe.com.

Load Stripe.js directly
<script src="https://js.stripe.com/v3/"></script>
02
Load and use Stripe.js as a model

This is done through Stripe's provided npm package.

Once loaded, initialize it with a publishable key.

If loaded from a script:

Initializing Stripe.js from script
// Client side
const stripe = Stripe('pk_test_...')

If loaded from a JS module:

Initializing Stripe.js from a JS module
// Client side
import { loadStripe } from '@stripe/stripe-js'
const stripe = await loadStripe('pk_test_...')

This library will be used to access the Stripe API and create payment intents. To install the npm package:

Install Stripe npm package
npm i --save stripe

Initialize Stripe with a secret key:

Initialize Stripe with a secret key
// Server side
const stripe = require('stripe')('sk_test_...')

Creating iDEAL elements using Stripe elements:

Creating iDEAL elements with Stripe elements
// Client side
const stripe = Stripe('pk_test_...');

const elements = stripe.elements();
const ideal = elements.create('idealBank', options); // 'options' is an optional object
ideal.mount('#stripe-ideal');

There are several options for customization.

Important: in the above example, the element will be mounted in an HTML tag with the ID stripe-ideal. Make sure it exists on the page.

​Once a customer enters all required information, it's necessary to create a payment method:

Creating a payment method
// Client side
const stripe = Stripe('pk_test_...');

await stripe.createPaymentMethod({
  type: 'ideal',
  ideal: idealElement,
  billing_details: {
    name: 'Jenny Rosen',
  },
});

​ This call returns one of:

  • result.paymentMethod: a PaymentMethod that was created successfully.
  • result.error: a server or client-side validation error. Refer to the Stripe API reference for all possible errors.

To create a payment intent, pass the payment method created earlier, along with amount and return_url to which the customer will be redirected after authorizing payment:

Create a payment intent
// Server side
const stripe = require('stripe')('sk_test_...');

await stripe.paymentIntents.create({
  payment_method: '<payment_method_id>',
  amount: '<amount in cents>',
  currency: 'eur',
  payment_method_types: 'ideal',
  confirmation_method: 'manual',
  confirm: true,
  return_url: '<return_url>',
});

This call returns one of:

  • result.paymentIntent: a PaymentIntent that was created successfully.
  • result.error: a server or client-side validation error. Refer to the Stripe API reference for all possible errors.

​ If a payment intent was created successfully, authorize the payment:

Payment authorization
// Client side
const stripe = Stripe('pk_test_...');

await stripe.handleCardAction(paymentIntent.client_secret);

​ This method will redirect the customer to authorize payment. After authorization, the customer will be redirected back to your site at the address specified when creating the payment intent (return_url).

​When redirecting to your site, the URL query will contain parameters with information about the payment: ​

  • redirect_status: Payment authorization status (succeeded or failed)
  • payment_intent: Unique identifier for the PaymentIntent
  • payment_intent_client_secret: A client secret related to the PaymentIntent object

Finally, add the relevant payment details to a Swell cart or order:

Add relevant payment details to Swell cart or oder
const billing = {
  method: 'ideal',
  ideal: {
    token: '<payment_method_id>'
  },
  intent: {
    stripe: {
      id: '<payment_intent_id>'
    }
  }
}

// Using Swell JS library
await swell.cart.update({ billing })

// Using Swell Node.js library
await swell.put('/carts/<id>', { billing })

To make a Klarna payment, create a source object. Klarna does not require using Stripe elements.

Klarna integration with Stripe
// Client side
const stripe = Stripe('pk_test_...');

await stripe.createSource({
  type: 'klarna',
  flow: 'redirect',
  amount: '<amount>',
  currency: '<iso currency code>',
  klarna: {
    product: 'payment',
    purchase_country: '<Two letter ISO country code>',
  },
  source_order: {
    items: '<items>',
  },
  redirect: {
    return_url: '<return_url>',
  },
 });

​ See Stripe docs for more details on creating a source object.

​When redirecting to your site, the URL query will contain parameters with information about the payment: ​

  • redirect_status: Authorization status (succeeded, canceled or failed)
  • source: Unique identifier for the Source

Finally, add the relevant payment details to a Swell cart or order:

Add Klarna payment details to Swell cart or order
const billing = {
  method: 'klarna',
  klarna: {
    source: '<source_id>'
  }
}

// Using Swell JS library
await swell.cart.update({ billing })

// Using Swell Node.js library
await swell.put('/carts/<id>', { billing })

​If the source was created successfully, redirect the customer to the URL address returned in the source object (source.redirect.url). After authorization, the customer will be redirected back to your site at the address specified when creating the source (return_url).

Redirect the customer to the Klarna payment page:

Direct user to Klarna payment page
import swell from 'swell-js';

swell.init('my-store', 'pk_...');

const form = document.getElementById('payment-form');
form.addEventListener('submit', function(event) {
  event.preventDefault();
  showLoading();

  await swell.payment.tokenize({
    klarna: {
      onError: (err) => {
        // inform the customer there was an error
      },
    }
  });

  hideLoading();
});

Once the user enters the payment details and confirms payment, they will be redirected to the checkout page. Next, update the cart billing by calling the following:

Update cart billing
import swell from 'swell-js'

swell.init('my-store', 'pk_...')

swell.payment.handleRedirect({
  klarna: { 
    onError: (err) => {
      // inform the customer there was an error
    }, 
    onSuccess: () => {
      swell.cart.submitOrder()
    }
  }
});

Make sure the payment page and cart billing localizations match. This is because Klarna sets the localization on the payment page based on the country in the billing.

​To make a Bancontact payment, create a source object. Bancontact does not require using Stripe elements.

Bancontact intergration
// Client side
const stripe = Stripe('pk_test_...');

await stripe.createSource({
  type: 'bancontact',
  amount: '<amount>',
  currency: 'eur', // Bancontact must always use Euros
  owner: {
    name: '<name>',
  },
  redirect: {
    return_url: '<return_url>',
  },
 });

See Stripe docs for more details on creating a source object.

​If the source was created successfully, redirect the customer to the URL address returned in the source object (source.redirect.url). After authorization, the customer will be redirected back to your site at the address specified when creating the source (return_url).

​When redirecting to your site, the URL query will contain parameters with information about the payment: ​

  • redirect_status: Authorization status (succeeded, canceled or failed)
  • source: Unique identifier for the Source

Finally, add the relevant payment details to a Swell cart or order:

Add Bancontact payment details to Swell cart or order
const billing = {
  method: 'bancontact',
  bancontact: {
    source: '<source_id>'
  }
}

// Using Swell JS library
await swell.cart.update({ billing })

// Using Swell Node.js library
await swell.put('/carts/<id>', { billing })

Start by enabling the payment method and linking a Saferpay account to your Swell store under Settings > Payments in the dashboard.

To create a transaction, it is necessary to initialize the Saferpay payment page. This can be done in the following ways:

Tokenization method

Saferpay tokenization method
import swell from 'swell-js'

swell.init('my-store', 'pk_...')

await swell.payment.tokenize({
  card: {
    intent: {
      // optional
      Payment: {
        Amount: {
          Value: '<amount>',
          CurrencyCode: '<currency>'
        },
        Description: '<description>'
      },
      PaymentMethods: ['<payment methods list>'],
      ReturnUrls: {
        Success: '<success_return_url>',
        Fail: '<fail_return_url>',
        Abort: '<abort_return_url>'
      }
    },
    onError: err => {
      // inform the customer there was an error
    }
  }
})

As a result of calling tokenize(), the Saferpay payment page will be initialized, the transaction token will be set in the cart billing (billing.intent.saferpay), and then the user will be automatically redirected to enter payment data.

Intent creation method

Saferpay intent creation method
import swell from 'swell-js'

swell.init('my-store', 'pk_...')

await swell.payment
  .createIntent({
    gateway: 'saferpay',
    intent: {
      Payment: {
        Amount: {
          Value: '<amount>',
          CurrencyCode: '<currency>'
        },
        Description: '<description>'
      },
      PaymentMethods: ['<payment methods list>'],
      ReturnUrls: {
        Success: '<success_return_url>',
        Fail: '<fail_return_url>',
        Abort: '<abort_return_url>'
      }
    }
  })
  .then(intent => {
    // save 'intent.token' for further processing of the transaction
    // redirect the user to 'intent.return_url' to enter payment information
  })
  .catch(err => {
    // inform the customer there was an error
  })

See Saferpay PaymentPage Initialize docs for more details on configuring a payment page.

You can independently initialize the Saferpay payment page using Saferpay API, and then redirect the user to this page to enter payment information.

After entering payment information on the payment page, the customer will be redirected back to your site at the address specified when initializing the payment page. See Handling redirect actions section for payment processing.

Start by enabling the payment method and linking a Paysafecard account to your Swell store under Settings > Payments in the dashboard.

Direct user to Paysafecard payment page
import swell from 'swell-js';

swell.init('my-store', 'pk_...');

const form = document.getElementById('payment-form');
form.addEventListener('submit', function(event) {
  event.preventDefault();
  showLoading();

  await swell.payment.tokenize({
    paysafecard: {
      onError: (err) => {
        // inform the customer there was an error
      },
    }
  });

  hideLoading();
});

Once the user enters the payment details and confirms payment, they will be redirected to the checkout page. Next, update the cart billing by calling the following:

Update cart billing
import swell from 'swell-js'

swell.init('my-store', 'pk_...')

swell.payment.handleRedirect({
  paysafecard: { 
    onError: (err) => {
      // inform the customer there was an error
    }, 
    onSuccess: () => {
      swell.cart.submitOrder()
    }
  }
});

Start by enabling the payment method in the Credit cards section and linking a Quickpay account to your Swell store under Settings > Payments in the dashboard.

Direct the user to QuickPay payment page
import swell from 'swell-js';

swell.init('my-store', 'pk_...');

const form = document.getElementById('payment-form');
form.addEventListener('submit', function(event) {
  event.preventDefault();
  showLoading();

  await swell.payment.tokenize({
    card: {
      onError: (err) => {
        // inform the customer there was an error
      },
    }
  });

  hideLoading();
});

Once the user enters the payment details and confirms payment, they will be redirected to the checkout page. Next, update the cart billing by calling the following:

Update cart billing
import swell from 'swell-js'

swell.init('my-store', 'pk_...')

swell.payment.handleRedirect({
  card: { 
    onError: (err) => {
      // inform the customer there was an error
    }, 
    onSuccess: () => {
      swell.cart.submitOrder()
    }
  }
});

You will need to enable Apple Pay with Stripe or Braintree. See this resource to learn how to enable Apple Pay within your Swell account.

Apple Pay with Swell.js
swell.payment.createElements({
  apple: {
    elementId: '<dom-element-id>', // Default: applepay-button
    style: {
      theme: '<button-theme>', // Default: black
      type: '<button-type>' // Default: plain
      height: '<button-height>' // Default: 40px
    },
    require: {
      // Requested data in Apple Pay modal
      shipping: true, // Default: false
      name: true, // Default: false
      email: true, // Default: false
      phone: true, // Default: false
    },
    classes: {
      base: '<button-container-class>', // Optional, the base class applied to the container
      // The following classes only work with Stripe Apple Pay
      complete: '<button-complete-class>', // Optional, the class name to apply when the Element is complete
      empty: '<button-empty-class>', // Optional, the class name to apply when the Element is empty
      focus: '<button-focus-class>', // Optional, the class name to apply when the Element is focused
      invalid: '<button-invalid-class>', // Optional, the class name to apply when the Element is invalid
      webkitAutofill: '<button-webkit-autofill-class>', // Optional, the class name to apply when the Element has its value autofilled by the browser (only on Chrome and Safari)
    },
    onSuccess: () => {}, // Optional, called on submit Apple Pay modal
    onError: (error) => {}, // Optional, called on payment error
  }
});

See the following documentation for more information on button options:

You will need to enable Google Pay with Stripe or Braintree. See this resource to learn how to enable Google Pay within your Swell account.

Google Pay with Swell.js
swell.payment.createElements({
  google: {
    elementId: '<dom-element-id>', // Default: googlepay-button
    locale: '<button-locale>', // Default: en
    style: {
      color: '<button-color>', // Default: black
      type: '<button-type>', // Default: buy
      sizeMode: '<button-size-mode>', // Default: fill
    },
    require: {
      // Requested data in Google Pay modal
      shipping: true, // Default: false
      email: true, // Default: false
      phone: true, // Default: false
    },
    classes: {
      base: '<button-container-class>', // Optional, the base class applied to the container
    },
    onSuccess: () => {}, // Optional, called on submit Google Pay modal
    onError: (error) => {}, // Optional, called on payment error
  }
});

See Google documentation for more information on button options.