Status Callbacks

Learn to track Klarna HPP session updates via status callbacks. Activate by adding a URL to merchant_urls. Callbacks include an event_id and session status in JSON, secured by HTTPS and one-time tokens.

It is possible when integrating HPP to received status changes callbacks to a certain URL. This address that is unique to every session will be called by our systems whenever the status of the session is updated. This is really handy to create interaction whenever something happens and avoid to have a costly polling mechanism.

It is advised to read our guide on how to track the HPP Session status changes.

sequenceDiagram autonumber participant A as Consumer participant B as Browser participant C as HPP participant D as Merchant Backend C -->> A: A link to the HPP is provided to the consumer by e-mail, SMS, QR code or simply browser redirection B ->> C: Request url note over A,D: The consumer arrives to the HPP and the distribution of the link was successful, the Merchant backend is notified to be able to act on it. On integration with multiple actors, it may allow to tell the other actor (a clerk) that the consumer is filling the application. C -->>D: Notification IN_PROGRESS alt Successful authorization A ->>C: Presses pay button note over A,D: The consumer has a successful authorization from Klarna and the payment can be satisfied. The HPP session is considered as COMPLETED but it is needed from the Merchant to place the order. C -->>D: Notification COMPLETED note over A,D: Depending on how the HPP session was created, the consumer will receive as a result a hosted confirmation page or a redirection to your website using merchant_urls. C ->>B: Result else Declined authorization A ->>C: Presses pay button note over A,D: Although the consumer wants to pay with Klarna, its application may be declined, which is known as a Failure. The HPP session is considered as FAILED, but the consumer can still try again until they cancel the HPP session or the merchant integration does it. C -->>D: Notification FAILED note over A,D: Depending on how the HPP session was created, the consumer will receive as a result a hosted confirmation page or a redirection to your website using merchant_urls. C ->>B: Result else Bank and error cases note over A,D: The consumer chooses to cancel the order or to go back to the checkout progress. All cases can be interpreted the same way as there is just a notification that will send the new status of the HPP session. Depending if it is a back button or cancellation request, the consumer may or may not come back to the same HPP session. A ->>C: Presses back button or cancellation button C -->>D: Notification BACK or CANCELLED note over A,D: Depending on how the HPP session was created, the consumer will receive as a result a hosted confirmation page or a redirection to your website using merchant_urls. C -->>B: Result else Timeout of the HPP session note over A,D: The consumer may not use the back button or cancel button and just leave the page, or choose another payment method using the previous page feature of their browser. In these cases, the HPP system loses track of the consumer. A timer is set for every HPP session and will turn the status to TIMEOUT. This timer will depend on how the HPP session was created. C -->>D: Notification TIMEOUT end

Activating Callbacks

When creating the HPP SessionHPP Session, you need to pass an URL in the status_update field of the merchant_urls. This URL will be called by HPP each time the status of the HPP Session is updated on Consumers actions, it contains the new status of the HPP Session the same way it would be gotten by reading the HPP Session from the read session endpoint of the API.

Definition of callbacks calls

Description	POST the Status of the HPP Session to the integrator
URL	HPP will use merchant_urls.status_updatereceived in the create session call
Operation	POST
Example	curl -X POST `merchant_urls.status_update` --data “`content`”

Body of the callback

Field Key	Type	Description
event_id	String	Identifier of the event, allowing the integrator to de-duplicate operations if needed.
session	JSON	And object representing the session status when the event occurred. Content is exactly the same as one could get from the read session endpoint.

Expected response and retry strategy

The calls made to the status_update URL will be made by HPP without waiting for any response from your server. It is expected from the the URL to send back a 2xx status code response.

In case no response is gotten in less than 3 seconds, there will be a retry after a few seconds. This mechanism will happen up to three times, with 4 calls being made for the same events. If of these calls are unanswered, the callback mechanism will end.

Securing the callbacks

The URL provided as status_update must be over HTTPS, but to be able to authenticate that the callback comes from Klarna, it is advised to generate a one time token that you will only use for this specific HPP Session.

This lets you validate that the call made to you on an update of status is only made by us.

JSON

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{
    "merchant_urls": {
        "status_update": "https://example.com/statsCallbackEndpoint?hppSessionId={{session_id}}&secretToken=7d1cbc3b-b30c-4be2-a8c4-dc76482d7bf6"
    }
}

The value passed here 7d1cbc3b-b30c-4be2-a8c4-dc76482d7bf6 could be something that is generated by the integrator for every new session.

Happy flow examples

These are the callbacks that an integration layer will get when an HPP Session is completed.

Consumer arrives on HPP

JSON

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{
  "event_id": "270b2adc-35a4-4524-800a-a5d2b8a96a2c",
  "session": {
    "session_id": "35bde117-ce5f-774f-9bcb-ec514a0963ad",
    "status": "IN_PROGRESS",
    "updated_at": "2019-05-13T14:51:46.288Z",
    "expires_at": "2019-05-15T13:51:43.507Z"
  }
}

Consumer completes Payment

Klarna Payments

To learn more about place_order_mode, read our guide on how to integrate Klarna Payments with HPP.

Default value for place_order_mode

JSON

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{
  "event_id": "27ba32b0-644b-4b22-94a9-dac503bcae18",
  "session": {
    "session_id": "39a1c773-bafd-754d-af1f-b30c592f1267",
    "status": "COMPLETED",
    "authorization_token": "a1a8f727-2756-6058-bd3c-40069be0994b",
    "updated_at": "2019-05-13T14:54:04.675Z",
    "expires_at": "2019-05-15T13:51:43.507Z"
  }
}

With place_order_mode as PLACE_ORDER or CAPTURE_ORDER

JSON

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{
  "event_id": "27ba32b0-644b-4b22-94a9-dac503bcae18",
  "session": {
    "session_id": "39a1c773-bafd-754d-af1f-b30c592f1267",
    "status": "COMPLETED",
    "order_id": "a1a8f727-2756-6058-bd3c-40069be0994b",
    "klarna_reference": "X438HG0Q",
    "updated_at": "2019-05-13T14:54:04.675Z",
    "expires_at": "2019-05-15T13:51:43.507Z"
  }