JavaScript client reference

The JavaScript client allows to create a payment form on your merchant website, using the following code:

<!DOCTYPE html>
<html>
<head>
  <meta name="viewport" 
   content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no" />
  <meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
  <meta http-equiv="X-UA-Compatible" content="IE=edge" />  

  <!-- Javascript library. Should be loaded in head section -->
  <script 
   src="https://api.systempay.fr/static/js/krypton-client/V4.0/stable/kr-payment-form.min.js" 
   kr-public-key="73239078:testpublickey_Zr3fXIKKx0mLY9YNBQEan42ano2QsdrLuyb2W54QWmUJQ" 
   kr-post-url-success="paid.html">
  </script>

  <!-- theme and plugins. should be loaded after the javascript library -->
  <!-- not mandatory but helps to have a nice payment form out of the box -->
  <link rel="stylesheet" 
  href="https://api.systempay.fr/static/js/krypton-client/V4.0/ext/classic-reset.css">
 <script 
  src="https://api.systempay.fr/static/js/krypton-client/V4.0/ext/classic.js">
 </script> 
</head>
<body>
  <!-- payment form -->
  <div class="kr-embedded" 
   kr-form-token="DEMO-TOKEN-TO-BE-REPLACED">

    <!-- payment form fields -->
    <div class="kr-pan"></div>
    <div class="kr-expiry"></div>
    <div class="kr-security-code"></div>

    <!-- payment form submit button -->
    <button class="kr-payment-button"></button>

    <!-- error zone -->
    <div class="kr-form-error"></div>
  </div>
</body>
</html>

<!DOCTYPE html>
<html>
<head>
  <meta name="viewport" 
   content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no" />
  <meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
  <meta http-equiv="X-UA-Compatible" content="IE=edge" /> 

  <!-- Javascript library. Should be loaded in head section -->
  <script 
   src="<?php echo $client->getClientEndpoint();?>/static/js/krypton-client/V4.0/stable/kr-payment-form.min.js"
   kr-public-key="<?php echo $client->getPublicKey();?>"
   kr-post-url-success="paid.php">
  </script>

  <!-- theme and plugins. should be loaded after the javascript library -->
  <!-- not mandatory but helps to have a nice payment form out of the box -->
  <link rel="stylesheet" 
   href="<?php echo $client->getClientEndpoint();?>/static/js/krypton-client/V4.0/ext/classic-reset.css">
  <script 
   src="<?php echo $client->getClientEndpoint();?>/static/js/krypton-client/V4.0/ext/classic.js">
  </script>
</head>
<body style="padding-top:20px">
  <!-- payment form -->
  <div class="kr-embedded"
   kr-form-token="<?php echo $formToken;?>">

    <!-- payment form fields -->
    <div class="kr-pan"></div>
    <div class="kr-expiry"></div>
    <div class="kr-security-code"></div>  

    <!-- payment form submit button -->
    <button class="kr-payment-button"></button>

    <!-- error zone -->
    <div class="kr-form-error"></div>
  </div>  
</body>
</html>

For more detailed documentation, go to Getting started: Single payment.

We make every effort to support all recent versions of the major browsers available on the market.

For security reasons and to deliver the best user experience to the majority of our merchants, we do not support browsers and operating systems that no longer receive security patches.

These browsers represent a minor part of the traffic making payments on the Internet.

We support:

Internet Explorer from version 10
Edge starting from version 17
Chrome from version 70
Firefox starting from version 64
Safari (Desktop and mobile) from version 11 onwards
Android native browser from Android 4.4 onwards
all the latest versions of IOS starting from iPhone 4S.

TLS 1.2 must be supported by the browser.

We proactively test most browsers, both mobile and desktop. However, it is possible that a combination of mobile + browser eludes our attention. In this case, please contact our support team.

If you want to support a combination that is not supported by our JavaScript client, you can also implement our form with redirect for these limit cases.

Also note that some antivirus or ad-blocker software may block our solution. Please contact support if you notice any improper detection.

Various parameters can be defined while loading the JavaScript client. For example, in order to define kr-public-key and kr-post-url-success:

  <!-- Javascript library. Should be loaded in head section -->
  <script 
   src="https://api.systempay.fr/static/js/krypton-client/V4.0/stable/kr-payment-form.min.js" 
   kr-public-key="73239078:testpublickey_Zr3fXIKKx0mLY9YNBQEan42ano2QsdrLuyb2W54QWmUJQ" 
   kr-post-url-success="paid.html">
  </script>

  <!-- Javascript library. Should be loaded in head section -->
  <script 
   src="<?php echo $client->getClientEndpoint();?>/static/js/krypton-client/V4.0/stable/kr-payment-form.min.js"
   kr-public-key="<?php echo $client->getPublicKey();?>"
   kr-post-url-success="paid.php">
  </script>

The available parameters are:

General settings:

Parameter	Required	Description
kr-public-key	yes	Public key for making a payment.
kr-language		Language used for displaying the form in Culture format (en-US).
kr-post-url-success		URL to which the form is submitted (POST method) in case of success.
kr-get-url-success		URL to which the form is submitted (POST method) in case of success.
kr-post-url-refused		URL called when all attempts have failed (POST method).
kr-get-url-refused		URL called when all attempts have failed (GET method).
kr-clear-on-error		Disables the removal of CVV in case of rejected transaction (true or false).
kr-hide-debug-toolbar		Hides the debug sidebar in test mode (true or false).
kr-spa-mode		if true, form is not automatically initialized (default is false).

Placeholder customization:

Parameter	Required	Description
kr-placeholder-expiry		Placeholder of the kr-expiry field (expiry date)
kr-placeholder-pan		Placeholder of the kr-pan field (card number).
kr-placeholder-security-code		Placeholder of the kr-security-code field (CVV)
kr-placeholder-identity-document-type		Placeholder of the ID document type field, if required (LATAM case)
kr-placeholder-identity-document-number		Placeholder of the ID number field, if required (LATAM case)
kr-placeholder-installment-number		Placeholder of the Payment method field
kr-placeholder-card-holder-mail		Placeholder of the e-mail field, if required (LATAM case)
kr-placeholder-card-holder-name		Placeholder of the cardholder name field, if required (LATAM case)

Personalization of animated labels (specific to the material theme):

Parameter	Required	Description
kr-label-expiry		Animated label of the kr-expiry field (expiry date)
kr-label-pan		Animated label of the kr-pan field (card number)
kr-label-security-code		Animated label of the kr-security-code (CVV) field
kr-label-identity-document-type		Animated label of the ID type field, if required (LATAM case)
kr-label-identity-document-number		Animated label of the ID number field, if required (LATAM case)
kr-label-installment-number		Animated label of the Payment method field
kr-label-card-holder-mail		Animated label of the e-mail field, if required (LATAM case)
kr-label-card-holder-name		Animated label of the cardholder name field, if required (LATAM case)

These parameters can also be overridden with the KR.setFormConfig() method. For example, to override the kr-post-url-success parameter:

KR.setFormConfig({
        'kr-post-url-success': 'https://my.site'
    }).then(({
            KR
        }) => {
            /* there is no error */
        );

Warning, if the kr-post-url-success and kr-get-url-success parameters are defined simultaneously, the POST method will have priority. The same applies to kr-post-url-refused and kr-get-url-refused*.

It is possible to attach custom JavaScript callbacks to different events. The JavaScript client supports the following events:

Parameter	Description
KR.onBrandChanged()	Called when the card brand has been detected.
KR.onError()	Allows to be notified when an error occurs.
KR.onFocus()	One of the form fields gets focus.
KR.onFormCreated()	The payment form is ready but the content of iframes has not loaded yet.
KR.onFormReady()	The form is ready to be used.
KR.onInstalmentChanged()	Called when the buyer selects the number of installments for the payment
KR.onLoaded()	First event called before creating the form.
KR.onSubmit()	Called just before the form is posted.
KR.button.onClick()	Called when the buyer clicks on the form button.

All events return promises, allowing you to integrate them into a chain. See Working in asynchronous environment for more information.

The callback defined in KR.onBrandChanged() is called each time a card brand is detected. Example of integration:

  <script type="text/javascript">
    $(document).ready(function() {
          KR.onBrandChanged( function({KR, cardInfo}) {
            var myMessage = "brand selected: " + cardInfo.brand;

            $("#custommessage").html(myMessage);
          });
    });
  </script>

The cardInfo object contains the brand property which can take the following values:

amex
cb
mastercard
maestro
visa_electron
visa

To view the complete list, see the reference documentation of the effectiveBrand parameter here: Payment.

KR.onError() allows to intercept errors before they appear.

Example of interception of error messages:

  <script type="text/javascript">
    $(document).ready(function() {
          KR.onError( function(event) {
            var code = event.errorCode;
            var message = event.errorMessage;
            var myMessage = code + ": " + message;

            document.getElementsByClassName("customerror")[0].innerText = myMessage;
          });
    });
  </script>

After that, error messages will automatically appear in the following element, if it is present:

When several errors are generated, they are merged into one single error. The children property will contain the details of all errors:

{
    "errorCode": "CLIENT_300",
    "errorMessage": "Invalid form data",
    "children": [{
        "errorCode": "CLIENT_301",
        "errorMessage": "Invalid card number",
        "field": "pan",
        (...)
    }, {
        "errorCode": "CLIENT_302",
        "errorMessage": "Invalid expiry date",
        "field": "expiryDate",
        (...)
    }, {
        "errorCode": "CLIENT_303",
        "errorMessage": "Invalid security code",
        "field": "securityCode",
        (...)
    }],
    "detailedErrorCode": null,
    "detailedErrorMessage": null,
    (...)
}

For more information on errors, go to: Managing errors (JS client)

Kr.onFocus() allows to be notified when a form field is in focus:

Example of integration:

  <script type="text/javascript">
    $(document).ready(function() {
          KR.onFocus( function(event) {
            var myMessage = "focus on: " + event.field;

            $("#custommessage").html(myMessage);
          });
    });
  </script>

If the card number field is in focus, the event variable will take the following value:

{
    "field":"pan",
    "formId":"F73867",
    "_type":"krypton/focus"
}

KR.onInstalmentChanged() allows you to be notified when the buyer selects the number of installments.

This event will be available in early March 2021.

KR.onSubmit() allows to intercept information about the authorized transaction before the form makes a POST to the URL defined with kr-post-success-url.

Example of integration:

  <script type="text/javascript">
    $(document).ready(function() {
      KR.onSubmit( function(event) {
        /* Change the button label to the orderStatus */
        $(".kr-payment-button > span:first").html(event.clientAnswer.orderStatus);
        $(".kr-spinner").hide();
        $(".kr-payment-button > span:first").show();
        
        /* return values:
         * true: kr-post-success-url is called using POST
         * false: kr-post-success-url is not called, execution stops.
         */
        return false;
      });
    });
  </script>

The object contained in event is the same as the one posted by the form. For more details, go to: Browser return.

The behavior varies depending on the boolean returned by your function:

Return value	Behavior
true	The JavaScript client performs a POST on kr-post-success-url.
false	The POST with kr-post-success-url is not made. You manage the post-payment action yourself.

KR.button.onClick() allows for custom processing before the JavaScript client validates the form and makes the call to create a transaction.KR.button.onClick() accepts either a callback or a promise as a parameter.

You can stop the execution string by returning false at the end of processing:

Return value	Behavior
false	The execution is interrupted. Error handling does not take place. The transaction is not created.
true	The execution continues normally when the callback is executed.

Several methods are available for interacting with the JavaScript client:

Parameter	Description
KR.closePopin()	Closes the pop-in (if open).
KR.field.focus()	Gives focus to an embedded form field.
KR.openPopin()	Opens the pop-in (if closed).
KR.setFormConfig()	Allows to override the JavaScript client configuration, see the next section.
KR.setShopName()	Changes the name of the shop defined in the pop-in header.
KR.setFormToken()	Shortcut for changing the formToken of the current form.
KR.validateForm()	Triggers local validation of the form.

All events return promises, allowing you to integrate them into a chain. See Working in asynchronous environment for more information.

To give focus to a form field, you can use the KR.field.focus(FIELD_CLASS) method. You must pass the class of the embedded form field as a parameter.

For example, to add a button that will set focus on the expiry date field:

This method allows to override the initialization parameters, as well as the following elements:

Use	Description
KR.setFormConfig({formToken: “NEW_FORM_TOKEN”});	Changes the current formToken.
KR.setFormConfig({language: “fr-FR”});	Changes the language of the payment form and error messages.

This method returns a promise.

This method checks locally if the form is valid. It returns a promise:

then() is called when the form is valid. result will be set to null.
catch() is called when the form is invalid. result contains the details of the error.

Example of a call:

KR.validateForm().then( ({KR, result}) => {

    /* there is no error */
    /* result == null */
    }

)
.catch( ({KR, result}) => {

    /* Get the error message */
    var code = result.errorCode;
    var message = result.errorMessage;
    var myMessage = code + ": " + message;
    console.log(myMessage);

    /* if you have defined a callback using      */
    /* result.onError(), you can trigger it calling: */
    return result.doOnError();
    }

);

Once you have intercepted the errors, you can trigger the KR.onError() event manually by callingresult.doOnError();.

The payment button is automatically added to your form using the following code:

    <!-- payment form submit button -->
    <button class="kr-payment-button"></button>

    <!-- payment form submit button -->
    <button class="kr-payment-button"></button>

There are numerous benefits to using our payment button:

The labels are translated automatically.
The amount is automatically formatted and updated.
We handle the pending transition animation for you
The button automatically changes to read-only mode if necessary

If you want to manage the button label yourself, simply add it as follows:

You can also insert a variable that represents the amount and currency. The JavaScript client will automatically replace them:

Here you will find the frequently asked questions about the JavaScript client.

First, you have to be developing from a web server. The test page must be accessed with http:// and not with file://.

If you use the ionic or cordova framework, you must explicitly declare the domain names that can be called by the JavaScript client. To do this, add the folowing in config.xml:

<allow-navigation href="" />

More information here.

If your website uses CSP (Content Security Policy), you must allow the JavaScript client to create its IFrames. To do this, you must add the following 3 instructions:

CSP directive	Values
connect-src	https://api.systempay.fr
frame-src	https://api.systempay.fr
script-src	https://api.systempay.fr

Example of adding your page head to the meta section:

<meta
  http-equiv="Content-Security-Policy"
  content="
    connect-src https://api.systempay.fr;
    frame-src https://api.systempay.fr;
    script-src https://api.systempay.fr;"
/>

(More information on the CSP here.)[https://developer.mozilla.org/en-US/docs/Web/HTTP/CSP]

If you use an external fraud detection engine (such as monitor+, clearsale, etc.), you should also add:

CSP directive	Values
connect-src	https://secure.systempay.fr
frame-src	https://secure.systempay.fr
script-src	https://secure.systempay.fr

To see all the advanced use cases, go to the following articles:

Description	Article
Adding custom form fields	Additional fields
Performing a single payment	Start: Single payment
Transmit the fields based on your needs	Use cases
Handling embedded form errors	Error handling
Handling new payment attempts (retry)	Handling retries
Event and method reference of the JS client	JavaScript Client Reference
Pre-configured themes and personalization with CSS	Themes
Switch from redirected form to embedded form	Migrating the form with redirect

EMBEDDED FORM

REST WEB SERVICES

JavaScript client reference

Supported platforms

Initialization parameters

Events

KR.onBrandChanged()

KR.onError()

KR.onFocus()

KR.onInstalmentChanged()

KR.onSubmit()

KR.button.onClick()

Methods

KR.field.focus()

KR.setFormConfig()

KR.validateForm()

Button personalization

Frequently Asked Questions

How to correct CORS or "Unable to post message" errors upon payment?

How to configure the CSP (Content Security Policy)

Advanced use

Search

EMBEDDED FORM

REST WEB SERVICES

JavaScript client reference

Supported platforms

Initialization parameters

Events

KR.onBrandChanged()

KR.onError()

KR.onFocus()

KR.onInstalmentChanged()

KR.onSubmit()

KR.button.onClick()

Methods

KR.field.focus()

KR.setFormConfig()

KR.validateForm()

Button personalization

Frequently Asked Questions

How to correct CORS or "Unable to post message" errors upon payment?

How to configure the CSP (Content Security Policy)

Advanced use